Biomerica (BMRA) 10-K/A 14 Oct 21 2021 FY Annual report (amended) Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	May 31, 2021	Aug. 27, 2021	Nov. 30, 2020
Document Information Line Items
Entity Registrant Name	BIOMERICA INC
Document Type	10-K/A
Current Fiscal Year End Date	--05-31
Entity Common Stock, Shares Outstanding		12,510,210
Entity Public Float			$ 66,938,974
Amendment Flag	true
Amendment Description	As disclosed in our Current Report on Form 8-K filed on September 30, 2021, subsequent to the issuance of the Original Form 10-K, we determined that our calculation and expense of non-cash stock-based compensation, related to issued stock options, as reported in our consolidated financial statements, have been materially understated based on the application of accounting principles generally accepted in the United States. We are filing this Amendment No. 1 on Form 10-K/A to reflect restatements to our consolidated financial statements for the years ended May 31, 2021 and 2020 to correct such errors in our accounting for non-cash stock based compensation
Entity Central Index Key	0000073290
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	May 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Interactive Data Current	Yes

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	May 31, 2021	May 31, 2020
Current Assets:
Cash and cash equivalents	$ 4,199,311	$ 8,641,027
Accounts receivable, less allowance for doubtful accounts of $837,415 and $70,981 as of May 31, 2021 and 2020, respectively	1,455,051	1,765,871
Inventories, net	3,206,255	2,850,836
Prepaid expenses and other	370,290	1,509,083
Total current assets	9,230,907	14,766,817
Property and equipment, net of accumulated depreciation and amortization of $1,972,357 and $1,867,643 as of May 31, 2021 and 2020, respectively	310,520	279,379
Right of use assets, net of accumulated amortization of $469,077 and $231,489 as of May 31, 2021 and 2020, respectively	1,553,081	1,711,510
Investments	165,324	165,324
Intangible assets, net of accumulated amortization of $126,769 and $496,124 as of May 31, 2021 and 2020, respectively	294,830	168,655
Other assets	264,151	168,193
Total Assets	11,818,813	17,259,878
Current Liabilities:
Accounts payable and accrued expenses	583,380	986,711
Accrued compensation	388,896	278,627
Lease liability, current portion	327,944	211,809
Total current liabilities	1,300,220	1,477,147
Lease liability, net of current portion	1,291,570	1,569,678
Total Liabilities	2,591,790	3,046,825
Commitments and contingencies (Notes 1 and 9)
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, none issued and outstanding at May 31, 2021 and 321,429 issued and outstanding at May 31, 2020 and Preferred stock, undesignated, no par value, 4,428,571 shares authorized, none issued and outstanding at May 31, 2021 and 2020		25,714
Common stock, $0.08 par value, 25,000,000 shares authorized, 12,307,157 and 11,740,089 issued and outstanding at May 31, 2021 and 2020, respectively	984,571	939,205
Additional paid-in-capital	38,836,743	36,388,056
Accumulated other comprehensive loss	(47,956)	(39,841)
Accumulated deficit	(30,546,335)	(23,100,081)
Total Shareholders' Equity	9,227,023	14,213,053
Total Liabilities and Shareholders' Equity	11,818,813	17,259,878
5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, none issued and outstanding at May 31, 2021 and 321,429 issued and outstanding at May 31, 2020 and Preferred stock, undesignated, no par value, 4,428,571 shares authorized, none issued and outstanding at May 31, 2021 and 2020		25,714
Preferred Stock [Member]
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, none issued and outstanding at May 31, 2021 and 321,429 issued and outstanding at May 31, 2020 and Preferred stock, undesignated, no par value, 4,428,571 shares authorized, none issued and outstanding at May 31, 2021 and 2020

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($)	May 31, 2021	May 31, 2020
Allowance for doubtful accounts (in Dollars)	$ 837,415	$ 70,981
Accumulated depreciation and amortization (in Dollars)	1,972,357	1,867,643
Accumulated amortization, Right of Use Assets (in Dollars)	469,077	231,489
Accumulated amortization, Intangible Assets (in Dollars)	$ 126,769	$ 496,124
Common stock par value (in Dollars per share)	$ 0.08	$ 0.08
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	12,307,157	11,740,089
Common stock, shares outstanding	12,307,157	11,740,089
5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
Preferred Stock, Par Value (in Dollars per share)	$ 0.08	$ 0.08
Preferred Stock, shares authorized	571,429	571,429
Preferred Stock, shares issued	0	321,429
Preferred Stock, shares outstanding	0	321,429
Preferred Stock [Member]
Preferred Stock, shares issued	0	0
Preferred Stock, shares outstanding	0	0
Preferred Stock, No Par Value (in Dollars per share)	$ 0	$ 0
Preferred Stock, undesignated shares	4,428,571	4,428,571

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Income Statement [Abstract]
Net sales	$ 7,199,027	$ 6,692,711
Cost of sales	(6,832,742)	(4,954,484)
Gross Profit	366,285	1,738,227
Operating Expenses:
Selling, general and administrative	5,394,525	2,546,622
Research and development	2,471,453	1,932,570
Total operating expense	7,865,978	4,479,192
Loss from operations	(7,499,693)	(2,740,965)
Other Income:
Dividend and interest income	66,863	71,193
Interest expense	(367)	(9)
Total other income	66,496	71,184
Loss before income taxes	(7,433,197)	(2,669,781)
Provision for income taxes	(13,057)	(7,390)
Net loss	$ (7,446,254)	$ (2,677,171)
Basic net loss per common share (in Dollars per share)	$ (0.62)	$ (0.26)
Diluted net loss per common share (in Dollars per share)	$ (0.62)	$ (0.26)
Weighted average number of common and common equivalent shares:
Basic (in Shares)	11,928,941	10,166,296
Diluted (in Shares)	11,928,941	10,166,296
Net loss	$ (7,446,254)	$ (2,677,171)
Other comprehensive loss, net of tax:
Foreign currency translation	(8,115)	(3,310)
Comprehensive loss	$ (7,454,369)	$ (2,680,481)

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS` EQUITY - USD ($)	Series A Preferred Stock [Member]5% Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balances at May. 31, 2019		$ 774,173	$ 23,666,238	$ (36,531)	$ (20,422,910)	$ 3,980,970
Balances (in Shares) at May. 31, 2019		9,677,188
Exercise of stock options		$ 11,037	212,497			223,534
Exercise of stock options (in Shares)		137,958
Net proceeds from ATM		$ 133,995	10,098,862			10,232,857
Net proceeds from ATM (in Shares)		1,674,943
Issuance of preferred stock	$ 45,714		1,871,872			1,917,586
Issuance of preferred stock (in Shares)	571,429
Foreign currency translation				(3,310)		(3,310)
Conversion of preferred to common stock	$ (20,000)	$ 20,000
Conversion of preferred to common stock (in Shares)	(250,000)	250,000
Compensation expense in connection with options granted			538,587			538,587
Net loss					(2,677,171)	(2,677,171)
Balances at May. 31, 2020	$ 25,714	$ 939,205	36,388,056	(39,841)	(23,100,081)	14,213,053
Balances (in Shares) at May. 31, 2020	321,429	11,740,089
Balances at May. 31, 2020	$ 25,714	$ 939,205	36,388,056	(39,841)	(23,100,081)	14,213,053
Balances (in Shares) at May. 31, 2020	321,429	11,740,089
Balances at May. 31, 2020	$ 25,714	$ 939,205	36,388,056	(39,841)	(23,100,081)	14,213,053
Balances (in Shares) at May. 31, 2020	321,429	11,740,089
Balances at May. 31, 2020	$ 25,714	$ 939,205	36,388,056	(39,841)	(23,100,081)	14,213,053
Balances (in Shares) at May. 31, 2020	321,429	11,740,089
Exercise of stock options		$ 6,940	95,315			102,255
Exercise of stock options (in Shares)		86,750
Net proceeds from ATM		$ 12,712	998,763			1,011,475
Net proceeds from ATM (in Shares)		158,889
Foreign currency translation				(8,115)		(8,115)
Conversion of preferred to common stock	$ (25,714)	$ 25,714
Conversion of preferred to common stock (in Shares)	(321,429)	321,429
Compensation expense in connection with options granted			1,354,609			1,354,609
Net loss					(7,446,254)	(7,446,254)
Balances at May. 31, 2021		$ 984,571	$ 38,836,743	$ (47,956)	$ (30,546,335)	$ 9,227,023
Balances (in Shares) at May. 31, 2021		12,307,157

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Cash flows from operating activities:
Net loss	$ (7,446,254)	$ (2,677,171)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	138,267	129,172
Change in allowance on accounts receivable	766,434	(2,129)
Inventory reserve	1,550,594	17,714
Stock option expense	1,354,609	538,587
Reduction in deferred rent liability		(37,971)
Amortization of right-of-use asset	237,588	269,460
Changes in assets and liabilities:
Accounts receivable	(455,614)	(309,090)
Inventories	(1,906,013)	(717,460)
Prepaid expenses	1,138,793	(1,306,681)
Reduction in lease liability	(241,132)	(199,483)
Other assets	(95,958)	(41,361)
Accounts payable and accrued expenses	(403,331)	(12,883)
Accrued compensation	110,269	51,798
Net cash used in operating activities	(5,251,748)	(4,297,498)
Cash flows from investing activities:
Increase in intangibles	(159,727)	(85,319)
Purchases of property and equipment	(135,856)	(33,608)
Net cash used in investing activities	(295,583)	(118,927)
Cash flows from financing activities:
Proceeds from sale of common stock, net	1,011,475	10,232,857
Proceeds from sale of convertible preferred stock, net		1,917,586
Proceeds from exercise of stock options	102,255	223,534
Net cash provided by financing activities	1,113,730	12,373,977
Effect of exchange rate changes in cash	(8,115)	(3,310)
Net (decrease) increase in cash and cash equivalents	(4,441,716)	7,954,242
Cash and cash equivalents at beginning of year	8,641,027	686,785
Cash and cash equivalents at end of year	4,199,311	8,641,027
Cash paid during the year for:
Interest	367	9
Income taxes	27,171	7,390
Non-cash investing and financing activities:
Increase in right of use asset due to lease extension or establishment	79,159	1,942,999
Increase in lease liability due to lease extension or establishment	$ 79,159	$ 1,980,970

ORGANIZATION

ORGANIZATION	12 Months Ended
	May 31, 2021
Accounting Policies [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	NOTE 1: ORGANIZATION Biomerica Inc. and Subsidiaries (collectively the “Company”, “Biomerica”, “we”, “us”, or “our”) develops, patents, manufactures and markets advanced diagnostic and therapeutic products used at the point-of-care (physicians' offices and over-the-counter through drugstores and online) and in hospital/clinical laboratories for detection and/or treatment of medical conditions and diseases. Our diagnostic test kits are used to analyze blood, urine or fecal material from patients in the diagnosis of various diseases, food intolerances and other medical complications, or to measure the level of specific hormones, antibodies, antigens or other substances, which may exist in the human body in extremely small concentrations. The Company's products are designed to enhance the health and well-being of people, while reducing total healthcare costs. We are a global biomedical technology company that develops, patents, manufactures and markets advanced diagnostic and therapeutic products used at the point-of-care (in home and in physicians' offices) and in hospital/clinical laboratories for detection and/or treatment of medical conditions and diseases. The Company's products are designed to enhance the health and well-being of people, while reducing total healthcare costs. Our primary focus is the research and development of revolutionary, patented, diagnostic-guided therapy (“DGT”) products to treat gastrointestinal diseases, such as irritable bowel syndrome, and other inflammatory diseases. These products are directed at chronic inflammatory illnesses that are widespread and common, and as such address very large markets. Our medical diagnostic products are sold worldwide primarily in two markets: 1) clinical laboratories and 2) point-of-care (physicians' offices and over-the-counter drugstores). The diagnostic test kits are used to analyze blood, urine, or fecal specimens from patients in the diagnosis of various diseases and other medical complications, by measuring or detecting the existence and/or level of specific bacteria, hormones, antibodies, antigens or other substances, which may exist in a patient’s body, stools, or blood, often in extremely small concentrations. Due to the global 2019 SARS-CoV-2 novel coronavirus pandemic, in March 2020 we began redirecting and focusing a majority of our resources to develop, test, validate, seek regulatory approval for, and sell diagnostic products that indicate if a person has been infected by COVID-19. During fiscal 2021, we sold 2 primary types of Covid 19 tests; 1) antibody diagnostic tests that use a patient’s blood sample to detect if the patient has certain antibodies to COVID-19 that were created as part of their body’s immune response to a COVID-19 infection, even if the infection was asymptomatic, and 2) antigen tests that use a patient’s nasal fluid sample to detect if a patient is currently infected with the virus. Aside from the COVID-19 products we offer, the other products we sell are primarily focused on gastrointestinal diseases, food intolerances, diabetes and certain esoteric tests. These diagnostic test products utilize immunoassay technology. Most of our products are CE marked and/or sold for diagnostic use where they are registered by each country’s regulatory agency. In addition, some products are cleared for sale in the U.S. by the FDA.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	May 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	NOTE 2: SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES PRINCIPLES OF CONSOLIDATION The enclosed consolidated financial statements for the years ended May 31, 2021 and 2020 include the accounts of Biomerica, Inc. ("Biomerica") as well as its German subsidiary (BioEurope GmbH) and Mexican subsidiary (Biomerica de Mexico). All significant intercompany accounts and transactions have been eliminated in consolidation. ACCOUNTING ESTIMATES The preparation of the consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reported period. Estimates that are made include the allowance for doubtful accounts, which is estimated based on current as well as historical past practices with a customer; stock option forfeiture rates, which are calculated based on historical data; inventory obsolescence, which are based on projected and historical usage of materials; and lease liability and right-of-use assets, which are calculated based on certain assumptions such as borrowing rate, the likelihood of lease extensions to occur, asset valuation, among other things; and other items that may be necessary to estimate using current, historical and judgment based information. Actual results could materially differ from those estimates. MARKETS AND METHODS OF DISTRIBUTION Due to the Coronavirus global pandemic, the Company’s operations have been negatively impacted. The Company has faced disruptions in certain of the following areas, and may face further challenges from supply chain disruptions, loss of contracts and/or customers, closure of the Company’s manufacturing or distribution facilities or of the facilities of the Company’s suppliers, partners and customers, travel, shipping and logistical disruptions, government responses of all types, international business risks in countries where the Company makes and/or sells its products, loss of human capital or personnel at the Company, its partners and its customers, interruptions of production, customer credit risk, and general economic calamities. These ongoing pandemic related disruptions can materially negatively impact the Company’s operations and financial performance and may continue to have significant material negative impacts on the Company. LIQUIDITY The Company has incurred net losses and negative cash flows from operations and has an accumulated deficit of approximately $30.5 million as of May 31, 2021. Management expects to continue to incur significant costs as it advances its trials and development activities. On January 22, 2021, the Company filed a Prospectus Supplement for purposes of raising up to $15,000,000 to the base prospectus filed with the SEC on July 21, 2020 and declared effective by the SEC on September 30, 2020 and an ATM Agreement. The Company intends to use the net proceeds from such offering for general corporate purposes, including, without limitation, sales and marketing activities, clinical studies and product development, making acquisitions of assets, businesses, companies or securities, capital expenditures, and for working capital needs. Under an ATM Agreement, sales of the Placement Shares are deemed to be “at the market offering” as defined in Rule 415 promulgated under the Securities Act. The agent acts as sales agent under the ATM and uses commercially reasonable efforts to sell on the Company’s behalf all of the Placement Shares requested to be sold from time to time by the Company, consistent with its normal trading and sales practices, on mutually agreed terms between the agent and the Company. The Company has no obligation to sell any of the Placement Shares under the ATM Agreement, and may at any time suspend offers under, or terminate the ATM Agreement. During the year ended May 31, 2021, the Company sold 158,889 shares of its common stock at prices ranging from $7.06 to $7.79 under its Form S-3 Registration Statement ( File No. 333-239980) and ATM Agreement which resulted in gross proceeds of $1,177,394 and net proceeds to the Company of $1,011,475 after deducting commissions for each sale and legal, accounting and other fees related to the filing of the Form S-3. As a result of cash and cash equivalents on hand at May 31, 2021, management believes the Company has sufficient funds to operate through August 2022 and the ability to raise additional funds through the ATM noted above. FAIR VALUE OF FINANCIAL INSTRUMENTS The Company has financial instruments whereby the fair market value of the financial instruments could be different than that recorded on a historical basis. The Company's financial instruments consist of its cash and cash equivalents, accounts receivable, and accounts payable. The carrying amounts of the Company's financial instruments approximate their fair values. CONCENTRATION OF CREDIT RISK The Company maintains cash balances at certain financial institutions in excess of amounts insured by federal agencies. As of May 31, 2021, the Company had approximately $3,767,000 of uninsured cash. The Company does not believe it is exposed to any significant credit risks. The Company provides credit in the normal course of business to customers throughout the United States and in foreign markets. The Company performs ongoing credit evaluations of its customers and requires accelerated prepayment in some circumstances. For the years ended May 31, 2021 and 2020, the Company had two distributors and three distributors which accounted for a total of 60% and 57% of our net consolidated sales, respectively. Of this, for the years ended May 31, 2021 and 2020 one of the distributors mentioned above accounted for 33% and 26%, respectively, of net consolidated sales. At May 31, 2021 and 2020, the Company had two distributors and three distributors which accounted for a total of 73% and 80%, respectively, of gross accounts receivable. $2,292,466 and $1,836,852, respectively. For the year ended May 31, 2021, one vendor accounted for 58% of the purchases of raw materials. For the year ended May 31, 2020, one vendor accounted for a total of 59% of the purchases of raw materials. GEOGRAPHIC CONCENTRATION As of May 31, 2021 and 2020, approximately $803,000 and $613,000 of Biomerica's gross inventory and approximately $25,000 and $31,000, of Biomerica's property and equipment, net of accumulated depreciation, was located in Mexicali, Mexico, respectively. CASH AND CASH EQUIVALENTS Cash and cash equivalents consist of demand deposits and money market accounts with original maturities of less than three months. ACCOUNTS RECEIVABLE The Company extends unsecured credit to its customers on a regular basis. International accounts are usually required to prepay until they establish a history with the Company and at that time, they are extended credit at levels based on a number of criteria. Based on various criteria, initial credit levels for individual distributors are approved by designated officers and managers of the Company. All increases in credit limits are also approved by designated upper-level management. Management evaluates receivables on a quarterly basis and adjusts the allowance for doubtful accounts accordingly. Balances over ninety days old are usually reserved for unless collection is reasonably assured. Occasionally certain long-standing customers, who routinely place large orders, will have unusually large receivables balances relative to the total gross receivables. Management monitors the payments for these large balances closely and very often requires payment of existing invoices before shipping new sales orders. The Company has established a reserve of $837,415 for doubtful accounts as of May 31, 2021. The majority of this reserve has been established to cover 100% of outstanding accounts receivable from an international distributor. PREPAIDS The Company occasionally prepays for items such as inventory, insurance and other items. These items are reported as prepaids, until either the inventory is physically received or the insurance and other items are utilized. As of May 31, 2021, the prepaids were approximately $370,000, composed of prepayments to insurance and various other suppliers. As of May 31, 2020, approximately $1 million of the prepaids was an advance payment to one of our suppliers, which was subsequently refunded by the supplier when the Company determined it no longer needed the materials that had been ordered. INVENTORIES, NET The Company values inventory at the lower of cost (determined using a combination of specific lot identification and the first-in, first-out methods) or net realizable value. Management periodically reviews inventory for excess quantities and obsolescence. Management evaluates quantities on hand, physical condition, and technical functionality as these characteristics may be impacted by anticipated customer demand for current products and new product introductions. The reserve is adjusted based on such evaluation, with a corresponding provision included in cost of sales. Abnormal amounts of idle facility expenses, freight, handling costs and wasted material are recognized as current period charges and the allocation of fixed production overhead is based on the normal capacity of the production facilities. Inventories approximate the following at May 31: May 31, 2021 May 31, 2020 Raw materials $ 1,583,000 $ 1,635,000 Work in progress 1,006,000 988,000 Finished products 617,000 228,000 Total $ 3,206,000 $ 2,851,000 Reserves for inventory obsolescence are recorded as necessary to reduce obsolete inventory to estimated net realizable value or to specifically reserve for obsolete inventory that the Company intends to dispose of. As of May 31, 2021 and 2020, inventory reserves were approximately $1,617,000 and $67,000, respectively. Of the inventory reserve, $1,502,675 was related to a market downturn in our COVID-19 antibody test and materials, as the market shifted to COVID-19 PCR viral tests and antigen tests. PROPERTY AND EQUIPMENT, NET Property and equipment are stated at cost. Expenditures for additions and major improvements are capitalized. Repairs and maintenance costs are charged to operations as incurred. When property and equipment are sold, retired or otherwise disposed of, the related cost and accumulated depreciation or amortization are removed from the accounts, and gains or losses from sales, retirements and dispositions are credited or charged to income. Depreciation and amortization are provided over the estimated useful lives of the related assets, ranging from 5 to 10 years, using the straight-line method. Leasehold improvements are amortized over the lesser of the estimated useful life of the asset or the term of the lease. Depreciation and amortization expense on property and equipment amounted to $104,715 and $105,299 for the years ended May 31, 2021 and 2020, respectively. INTANGIBLE ASSETS, NET Intangible assets include trademarks, product rights, technology rights and patents, and are accounted for based on Accounting Standards Codification (“ASC”), ASC 350 Intangibles – Goodwill and Other (“ASC 350”). In that regard, intangible assets that have indefinite useful lives are not amortized but are tested at least annually for impairment or more frequently if events or changes in circumstances indicate that the asset might be impaired. Intangible assets are being amortized using the straight-line method over the useful life, not to exceed 18 years for marketing and distribution rights, 10 years for purchased technology use rights, and 20 years for patents. Amortization amounted to $33,552 and $23,873 for the years ended May 31, 2021 and 2020, respectively. The Company assesses the recoverability of these intangible assets by determining whether the amortization of the asset's balance over its remaining life can be recovered through projected undiscounted future cash flows. The Company uses a qualitative assessment to determine whether there was any impairment. No impairment adjustment was required as of May 31, 2021 or 2020. INVESTMENTS From time-to-time, the Company makes investments in privately-held companies. The Company determines whether the fair values of any investments in privately-held entities have declined below their carrying value whenever adverse events or changes in circumstances indicate that recorded values may not be recoverable. If the Company considers any such decline to be other than temporary (based on various factors, including historical financial results, and the overall health of the investee’s industry), a write-down to estimated fair value is recorded. Investments represent the Company’s investment in a Polish distributor which is primarily engaged in distributing medical products and devices. The Company currently has not written down the investment and no events have occurred which could indicate the carrying value of the investment to be greater than the fair value. The Company owns approximately 6% of the investee and, accordingly, applies the cost method to account for the investment. Under the cost method, investments are recorded at cost, with gains and losses recognized as of the sale date, and income recorded when received. SHARE-BASED COMPENSATION The Company follows the guidance of the accounting provisions of ASC 718 The grant date fair value of the award is recognized under the straight-line attribution method. In applying the Black-Scholes options-pricing model, assumptions used were as follows: 2021 2020 Dividend yield 0% 0% Expected volatility 71.19-107.53% 55.52-72.62% Risk free interest rate 0.34-1.18% 0.43-1.80% Expected Term 5.50-6.25 Years 3.75-6.25 Years REVENUE RECOGNITION The Company has various contracts with customers. All of the contracts specify that revenues from product sales are recognized at the time the product is shipped, customarily FOB shipping point, which is when the transfer of control of goods has occurred and at which point title passes. The Company does not allow for returns except in the event of defective merchandise and therefore does not establish an allowance for returns. In addition, the Company has contracts with customers wherein they receive purchase discounts for achieving specified sales volumes. The Company evaluated the status of these contracts as of May 31, 2021 and 2020 and does not believe that any additional discounts will be given through the end of the contract periods. Services for some contract work are invoiced and recognized for work that has been performed as the project progresses. The Company sells clinical lab products to domestic and international distributors, including hospitals and clinical laboratories, medical research institutions, medical schools and pharmaceutical companies. OTC products are sold directly to drug stores and e-commerce customers as well as to distributors. Physicians’ office products are sold to physicians and distributors, all of whom are categorized below according to the type of products sold to them. We also manufacture certain components on a contract basis for domestic and international manufacturers. Disaggregation of revenue: The following is a breakdown of revenues according to markets to which the products are sold: Year Ended May 31, 2021 May 31, 2020 Clinical lab $ 3,077,000 $ 2,922,000 Physician's office 2,801,000 2,195,000 Over-the-counter 766,000 1,270,000 Contract manufacturing 552,000 306,000 Lab supplies 3,000 - Total $ 7,199,000 $ 6,693,000 See Note 8 for additional information regarding revenue concentrations. SHIPPING AND HANDLING FEES The Company includes shipping and handling fees billed to customers in net sales. RESEARCH AND DEVELOPMENT Research and development costs are expensed as incurred. The Company expensed $2,471,453 and $1,932,570 of research and development costs during the years ended May 31, 2021 and 2020, respectively. INCOME TAXES The Company accounts for income taxes in accordance with ASC 740, Income Taxes (“ASC 740”). Deferred tax assets and liabilities arise from temporary differences between the tax bases of assets and liabilities and their reported amounts in the consolidated financial statements that will result in taxable or deductible amounts in future years and the benefits of net operating loss and tax credit carryforwards. These temporary differences and the benefits of net operating loss and tax credit carryforwards are measured using enacted tax rates. A valuation allowance is recorded to reduce deferred tax assets to the extent that management considers it is more likely than not that a deferred tax asset will not be realized. In determining the valuation allowance, the Company considers factors such as the reversal of deferred income tax assets, projected taxable income, and the character of income tax assets and tax planning strategies. A change to these factors could impact the estimated valuation allowance and income tax expense. At May 31, 2021 and 2020, in accordance with ASC 740, the Company has a valuation allowance for substantially all of its deferred tax assets. During the fiscal year ended May 31, 2021, this valuation allowance was increased to $5,904,000, which fully covers the tax asset of $5,904,000 . The Company accounts for its uncertain tax provisions by using a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not, based solely on the technical merits, that the position will be sustained in an audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the appropriate amount of the benefit to recognize. The amount of benefit to recognize is measured as the maximum amount which is more likely than not to be realized. The tax position is derecognized when it is no longer more likely than not capable of being sustained. On subsequent recognition and measurement the maximum amount which is more likely than not to be recognized at each reporting date will represent the Company’s best estimate, given the information available at the reporting date, although the outcome of the tax position is not absolute or final. Upon adopting the revisions in ASC 740, the Company elected to follow an accounting policy to classify accrued interest related to liabilities for income taxes within the “Interest expense” line and penalties related to liabilities for income taxes within the “Other expense” line of the consolidated statements of operations and comprehensive loss. ADVERTISING COSTS The Company reports the cost of all advertising as expense in the period in which those costs are incurred. Advertising costs were approximately $10,070 174 FOREIGN CURRENCY TRANSLATION The subsidiary located in Mexico operates primarily using the Mexican peso. The subsidiary located in Germany operates primarily using the U.S. dollar, with an immaterial amount of transactions occurring using the Euro. Accordingly, assets and liabilities of these subsidiaries are translated using exchange rates in effect at the end of the year, and revenues and costs are translated using average exchange rates for the year. The resulting adjustments to assets and liabilities are presented as a separate component of accumulated other comprehensive loss. There are no adjustments to foreign currency loss that are included in the consolidated statements of operations for the years ended May 31, 2021 and 2020. RIGHT-OF-USE ASSETS AND LEASE LIABILITY Incentive payments received from landlords are recorded as deferred lease incentives and are amortized over the underlying lease term on a straight-line basis as a reduction of rent expense. When the terms of an operating lease provide for periods of free rent, rent concessions, and/or rent escalations, the Company establishes a deferred rent liability for the difference between the scheduled rent payment and the straight-line rent expense recognized. This deferred rent liability was amortized over the underlying lease term on a straight-line basis as a reduction of rent expense. During the year ended May 31, 2020, the Company adopted ASC 842, Leases. As a result, the existing deferred rent liability was netted against the Right-of-Use Asset which was capitalized at that time. In February 2016, the Financial Accounting Standards Board (“FASB”) issued an accounting standards update which requires lessees to recognize most leases on the balance sheet with a corresponding right-of-use asset. Right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-Use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of fixed lease payments over the lease term. Leases are classified as financing or operating which will drive the expense recognition pattern. The Company has elected to exclude short-term leases. The Company adopted this guidance as of June 1, 2019, the required effective date, using the effective date transition method. An adjustment to opening accumulated deficit was not required in conjunction with adoption. The adoption of this statement resulted in a right-of-use asset being recorded in the amount of $1,942,999 and a lease liability being recorded in the amount of $1,980,970. On April 9, 2021, the Company exercised its second option to extend its lease for an additional five years. As part of that lease extension agreement, the Company was granted an additional right to extend its lease for five years, up through August 2031. However, given the recent growth in the Company’s operations, and the expectation that operations will continue to grow in the near future, the Company believes that it will be necessary to relocate into larger facilities by the end of the current lease term. Therefore, the Company has elected to not book the additional five-year extension option, from August 2026 to August 2031, into its right-of-use asset or its lease liability accounts. For additional information, see Note 9-Commitments and Contingencies. The Company has elected not to reassess whether expired or existing contracts contain leases, or reassess the classification of existing leases as of the adoption date. The Company leases office space and copy machines, all of which are operating leases. Most leases include the option to renew and the exercise of the renewal options is at the Company’s sole discretion. Options to extend or terminate a lease are considered in the lease term to the extent that the option is reasonably certain of exercise. The leases do not include the options to purchase the leased property. The depreciable life of assets and leasehold improvements are limited by the expected lease term. NET LOSS PER SHARE Basic loss per share is computed as net loss divided by the weighted average number of common shares outstanding for the period. Diluted loss per share reflects the potential dilution that could occur from common shares issuable through stock options, warrants and other convertible securities using the treasury stock method. The total amounts of anti-dilutive stock options not included in the loss per share calculation for the years ended May 31, 2021 and 2020 were 2,081,366 and 1,789,251, respectively. The Company also had 0 and 321,429 of Series A 5% Convertible Preferred Stock outstanding for the years ended May 31, 2021 and 2020, respectively. The 321,429 shares outstanding at May 31, 2020 were converted to common stock during the year ended May 31, 2021. SEGMENT REPORTING ASC 280, Segment Reporting (“ASC 280”), establishes standards for reporting, by public business enterprises, information about operating segments, products and services, geographic areas, and major customers. The Company’s operations are analyzed by management and its chief operating decision maker as being part of a single industry segment: the design, development, marketing and sales of diagnostic kits. REPORTING COMPREHENSIVE LOSS Comprehensive loss represents net loss and any revenues, expenses, gains and losses that, under GAAP, are excluded from net loss and recognized directly as a component of shareholders’ equity. Accumulated other comprehensive loss consists solely of foreign currency translation adjustments. RECENT ACCOUNTING PRONOUNCEMENTS Recent ASU's issued by the FASB and guidance issued by the SEC did not, or are not believed by management to, have a material effect on the Company’s present or future consolidated financial statements.

PROPERTY AND EQUIPMENT, NET

PROPERTY AND EQUIPMENT, NET	12 Months Ended
	May 31, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure [Text Block]	NOTE 3: PROPERTY AND EQUIPMENT, NET Property and equipment, net of accumulated depreciation, consist of the following at May 31: 2021 2020 Equipment $ 1,849,888 $ 1,921,833 Furniture, fixtures and leasehold improvements 432,989 225,189 Less accumulated depreciation (1,972,357) (1,867,643) Net property and equipment $ 310,520 $ 279,379

INTANGIBLE ASSETS, NET

INTANGIBLE ASSETS, NET	12 Months Ended
	May 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets Disclosure [Text Block]	NOTE 4: INTANGIBLE ASSETS, NET Intangible assets, net of accumulated amortization, consist of the following at May 31: 2021 2020 Licenses $ 182,176 $ 551,397 Patents 239,423 113,382 Less accumulated amortization-licenses (107,194) (487,989) Less accumulated amortization-patents (19,575) (8,135) Intangible asssets, net $ 294,830 $ 168,655 Expected amortization of intangible assets for the years ending May 31: 2022 $ 21,846 2023 20,058 2024 20,058 2025 19,071 2026 18,975 Thereafter 194,822 Total $ 294,830

ACCOUNTS PAYABLE AND ACCRUED EX

ACCOUNTS PAYABLE AND ACCRUED EXPENSES	12 Months Ended
	May 31, 2021
Payables and Accruals [Abstract]
Accounts Payable and Accrued Liabilities Disclosure [Text Block]	NOTE 5: ACCOUNTS PAYABLE AND ACCRUED EXPENSES The Company’s accounts payable and accrued expense balances consist of the following at May 31: 2021 2020 Accounts payable $ 431,621 $ 833,412 Accrued expense 151,759 153,299 Total $ 583,380 $ 986,711 As of May 31, 2021 and 2020 the Company had one vendor and two vendors which accounted for 17% and 27%, respectively, of accounts payable.

SHAREHOLDERS' EQUITY

SHAREHOLDERS' EQUITY	12 Months Ended
	May 31, 2021
Stockholders' Equity Note [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	NOTE 6: SHAREHOLDERS' EQUITY On February 24, 2020, the Company filed with the Secretary of State of Delaware a certificate of designation to authorize for issuance 571,429 shares of Series A 5% Convertible Preferred Stock. On February 26, 2020, the Company filed with the Secretary of State of Delaware a certificate of correction, correcting certain language defects in the previously filed certificate of designation. Please see below a description of the Series A 5% Convertible Preferred Stock shares that were issued in February 2020, and subsequently converted into registered common shares. STOCK OPTION AND RESTRICTED STOCK PLANS In August 2010, the Company adopted a stock option and restricted stock plan (the "2010 Plan") which provided that non-qualified options and incentive stock options and restricted stock covering an aggregate of 850,000 shares of the Company's unissued common stock could be granted to affiliates, employees or consultants of the Company. This plan was approved by shareholders in December 2010. The 2010 Plan expired in December 2020. Options granted under the 2010 Plan were granted at prices not less than 80% of the then fair market value of the common stock and will expire not more than 10 years after the date of grant. In December 2014, the Company adopted a stock option and restricted stock plan (the "2014 Plan") which provides that non-qualified options and incentive stock options and restricted stock covering an aggregate of 850,000 shares of the Company's unissued common stock may be granted to affiliates, employees or consultants of the Company. This plan was approved by shareholders in December 2014. The 2014 Plan expires in December 2024. Options granted under the 2014 Plan will be granted at prices not less than 80% of the then fair market value of the common stock and will expire not more than 10 years after the date of grant. In December 2017, the Company adopted a stock option and restricted stock plan (the “2017 Plan”) which provides that non-qualified options and incentive stock options and restricted stock covering an aggregate of 900,000 shares of the Company’s unissued common stock may be granted to affiliates, employees or consultants of the Company. This plan was approved by shareholders in December 2017. The 2017 Plan expires in December 2027. Options granted under the 2017 Plan will be granted at prices not less than 80% of the then fair market value of the common stock and will expire not more than 10 years after the date of grant. In February 2020, the Board approved the 2020 Stock Incentive Plan (the “2020 Plan”) and on December 11, 2020 the shareholders of the Company approved The Plan. The 2020 Plan authorizes the issuance of an aggregate number of common stock options and/or restricted common shares to be issued in an amount not to exceed 900,000. The 2020 Plan authorizes the issuance of common stock options and restricted common shares to employees, directors and consultants of the Company. During fiscal 2020, certain common stock options were granted under this plan. The Company accelerated the vesting of its former CFO’s options upon her voluntary resignation from the board of director on December 10, 2020. This resulted in the immediate vesting of 64,584 options and incremental expense of approximately $184,000 during the year ended May 31, 2021. Stock option expense during fiscal 2021 was $1,354,609. This included, by department, $956,898 for administrative, $204,509 for production, $125,439 for research and development and $67,763 for sales and marketing. Stock option expense during fiscal 2020 was $538,587. This included, by department, $416,953 for administrative, $66,444 for production, $40,254 for research and development and $14,936 for sales and marketing. Activity as to aggregate stock options outstanding is as follows: NUMBER OF STOCK OPTIONS EXCERCISE PRICE WEIGHTED AVERAGE EXERCISE Options outstanding at May 31, 2019 1,476,209 $0.82-$3.90 $ 2.07 Options granted 517,500 $2.68-$8.18 $ 4.47 Options excercised (137,958) $0.82-$3.90 $ 1.64 Options canceled or expired (66,500) $0.85-$8.18 $ 3.43 Options outstanding at May 31, 2020 1,789,251 $0.82-$8.18 $ 2.75 Options granted 430,616 $5.14-$8.70 $ 6.73 Options excercised (86,750) $0.82-$3.62 $ 1.20 Options canceled or expired (51,751) $2.35-$8.18 $ 4.77 Options outstanding at May 31, 2021 2,081,366 $0.82-$8.70 $ 3.59 The weighted average fair value of options granted during 2021 and 2020 was $6.73 and $4.47, respectively. The aggregate intrinsic value of options exercised during 2021 and 2020 was approximately $501,000 and $589,000, respectively. The aggregate intrinsic value of options outstanding at May 31, 2021 and 2020 was approximately $2,132,000 and $6,923,000, respectively. The aggregate intrinsic value of options vested and exercisable at May 31, 2021 and 2020 was approximately $1,872,000 and $4,442,000, respectively. The number of non-vested stock options included in the table above is as follows: Number of Stock options Non-vested shares at May 31, 2020 822,584 $ 3.78 Granted 430,616 6.73 Vested (409,459) 3.36 Forfeited (50,500) 4.80 Non-vested shares at May 31, 2021 793,241 $ 5.54 At May 31, 2021, total compensation cost related to non-vested stock option awards not yet recognized totaled approximately $2,156,000. The weighted-average period over which this amount is expected to be recognized is 2.59 years. The weighted average remaining contractual term of options that were exercisable at May 31, 2021 was 6.07 years. The following summarizes information about all of the Company's stock options outstanding at May 31, 2021. These options are comprised of those granted under the 2010, 2014, 2017 and 2020 plans. RANGE OF NUMBER WEIGHTED WEIGHTED NUMBER WEIGHTED $0.82-$1.04 216,000 3.75 $0.82 216,000 $0.82 $1.20-$2.81 1,024,500 6.45 $2.17 795,250 $2.02 $3.62-$8.70 840,866 8.00 $6.03 276,875 $4.54 COMMON STOCK ACTIVITY During the year ended May 31, 2020, options to purchase 137,958 shares of common stock were exercised at prices ranging from $0.82 to $3.90. Total net proceeds to the Company were $223,534. On December 1, 2017, the Company entered into an At Market Issuance Sales Agreement (or “ATM Agreement”) with an agent, and filed a prospectus supplement with the SEC pursuant under which the Company could offer and sell from time to time up to an aggregate of $7,000,000 of shares of the Company’s common stock, par value $0.08 per share (the “Placement Shares”), through the agent. From December 1, 2017 to March 19, 2020, the Company sold common stock resulting in $6,997,935 of gross proceeds under this ATM Agreement, of which $3,771,048 were sold during the year ended May 31, 2020. This At Market Issuance Agreement expired on July 20, 2020 upon the expiration of the Company’s Form S-3 registration statement base prospectus dated July 20, 2017. The Placement Shares sold and issued under this ATM Agreement have been registered under the Securities Act of 1933, as amended (the “Securities Act”), pursuant to the Registration Statement on Form S-3 (File No. 333-219130) (the “Registration Statement”), which was originally filed with the SEC on June 30, 2017 and declared effective by the SEC on July 20, 2017, the base prospectus contained within the Registration Statement, and the prospectus supplement related to the sale of shares under the ATM Agreement was filed with the SEC on December 1, 2017. On March 20, 2020, the Company filed a new prospectus supplement to the S-3 registration statement base prospectus dated July 20, 2017 for purposes of raising up to $12,500,000 from time to time pursuant to the terms of the ATM Agreement. This ATM Agreement expired on July 20, 2020 upon the expiration of the Company’s Form S-3 registration statement base prospectus dated July 20, 2017. Gross proceeds for the year ended May 31, 2020 were $6,817,330. There were no proceeds for the year ended May 31, 2021, for this July 20, 2017 Form S-3 registration statement. Combined Placement Shares sold under the ATM Agreements during the year ended May 31, 2020 under the two prospectus supplements dated December 1, 2017 and March 20, 2020 totaled 1,674,943 shares. Total net proceeds from the sale of Placement Shares under the two prospectus supplements during the year ended May 31, 2020 were $10,232,857 after deducting commissions for each sale and legal, accounting, and other fees related to the filing of the Form S-3. These shares were sold at prices ranging from $2.33 to $9.08 per share. On September 11, 2020, the Company filed a Pre-Effective Amendment No. 1 to the Form S-3 to register 571,429 shares of Biomerica common stock in connection with the Stock Purchase Agreement dated February 21, 2020, wherein the Company entered into a registration rights agreement with the selling stockholder, pursuant to which we agreed to file a registration statement registering the resale of the shares of our common stock issuable upon conversion of our Series A Preferred Stock issued to the selling stockholder under the Stock Purchase Agreement. On September 30, 2020, the Company received a Notice of Effectiveness from the Securities and Exchange Commission for the Form S-3 “shelf” Registration Statement filed on July 21, 2020 and amended on September 11, 2020. During the year ended May 31, 2020, 250,000 shares of common stock were converted from Preferred Stock as described below in “Preferred Stock Activity”. During the year ended May 31, 2021, options to purchase 86,750 shares of common stock were exercised at prices ranging from $0.82 to $3.62. Total net proceeds to the Company were $102,255. On January 22, 2021, the Company filed a Prospectus Supplement for purposes of raising up to $15,000,000 to the base prospectus filed with the SEC on July 21, 2020 and declared effective by the SEC on September 30, and an ATM Agreement. On May 21, 2021, in conjunction with the Company’s 2020 Stock Incentive Plan, that was approved by shareholders at the Company’s annual meeting in December 2020, the Company filed an S-8 Registration Statement to register up to 900,000 shares of the Company’s common stock that could be issued under this Plan. Under an ATM Agreements, sales of the Placement Shares are deemed to be “at the market offering” as defined in Rule 415 promulgated under the Securities Act. The agent acts as sales agent under the ATM and uses commercially reasonable efforts to sell on the Company’s behalf all of the Placement Shares requested to be sold from time to time by the Company, consistent with its normal trading and sales practices, on mutually agreed terms between the agent and the Company. The Company has no obligation to sell any of the Placement Shares under the ATM Agreement, and may at any time suspend offers under, or terminate the ATM Agreement. During the year ended May 31, 2021, 321,429 shares of common stock were converted from Preferred Stock as described below in “Preferred Stock Activity”. During the year ended May 31, 2021, the Company sold 158,889 shares of its common stock at prices ranging from $7.06 to $7.79 under its Form S-3 Registration Statement ( File No. 333-239980 ) and ATM Agreement which resulted in gross proceeds of $1,177,394 and net proceeds to the Company of $1,011,475 after deducting commissions for each sale and legal, accounting and other fees related to the filing of the Form S-3. PREFERRED STOCK ACTIVITY On February 24, 2020, the Company entered into and closed on a Stock Purchase Agreement (the “Stock Purchase Agreement”) with Palm Global Small Cap Master Fund LP (“Palm”) pursuant to which the Company agreed to sell and issue to Palm, and Palm agreed to purchase from the Company, 571,429 shares of the Company’s Series A 5% Convertible Preferred Stock, $0.08 par value per share for a purchase price of approximately $2 million, or $3.50 per Series A Convertible Preferred Stock. Under the terms of the Stock Purchase Agreement, each share of issued Convertible Preferred Stock can be converted at any time by Palm into one share of the Company’s common stock, subject to certain adjustments. The Series A 5% Convertible Preferred Stock accrued annual preferred dividends at a rate of $0.175 per Series A 5% Convertible Preferred Share. However, accruing dividends were payable only when, as, and if declared by the Board and the Company had no obligation to pay such accruing dividends. On March 24, 2020, Palm converted 250,000 shares of Convertible Preferred Stock into 250,000 shares of unregistered common stock. On July 21, 2020, the Company filed with the SEC a registration statement on Form S-3, that among other things, registered 571,429 common shares issued, or to be issued, to Palm upon conversion of the Convertible Preferred Stock into common shares. On September 30, 2020, the Company received a Notice of Effectiveness from the Securities and Exchange Commission for registration of these shares. On January 21, 2021 Palm Converted their remaining 321,429 Convertible Preferred Shares into registered common shares. At May 30, 2021, the Company had no shares of Preferred Stock outstanding. Under the terms of the Preferred Stock Purchase Agreement, none of the cumulative Dividends were paid to Palm during the period they owned the Preferred Stock. Once converted to common shares, Palm lost all rights to receive any past cumulative dividends.

INCOME TAXES

INCOME TAXES	12 Months Ended
	May 31, 2021
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	NOTE 7: INCOME TAXES Provision for income taxes for the years ended May 31 consists of the following: Years ended May 31, 2021 2020 Current: U.S. Federal $ - $ - Foreign Taxes Subsidiaries (12,257) (6,590) State and local (800) (800) Total current (13,057) (7,390) Deferred: U.S. Federal - - State and local - - Total deferred - - Income tax expense $ (13,057) $ (7,390) Provision for income taxes differs from the amounts computed by applying the U.S. Federal income tax rate applicable for each year ( 21 % for 2021 and 2020) to pretax income as a result of the following: Years ended May 31, 2021 2020 Computed "expected" tax benefit $ 1,560,971 $ 560,656 Increase (reduction) in income taxes resulting from: Change in valuation allowance (2,292,366) (1,152,000) State income taxes, net of federal benefit 217,559 83,202 Research and development tax credits 456,388 131,461 Permanent tax differences and other (88,051) 179,042 Stock based compensation benefit 144,699 196,839 Foreign taxes of subsidiaries (12,257) (6,590) Income tax expense $ (13,057) $ (7,390) The tax effect of significant temporary differences is presented below: As of May 31, 2021 2020 Deferred tax assets: Accounts receivable, principally due to allowance for doubtful accounts $ 200,000 $ 17,000 Inventory valuation 387,000 16,000 Compensated absences 85,000 64,000 Net operating loss carryforwards 3,194,000 2,286,000 Tax credit carryforwards 1,055,000 599,000 Deferred rent expense/Capitalized leases 15,000 17,000 Stock Options 613,000 304,000 Losses of foreign subsidiaries & Other, net 370,000 304,000 Accumulated depreciation and amortization (15,000) 5,000 Total deferred tax assets 5,904,000 3,612,000 Less valuation allowance (5,904,000) (3,612,000) Net deferred tax asset $ - $ - The Company has provided a valuation allowance of approximately $5,904,000 and $3,612,000 as of May 31, 2021 and 2020, respectively. The net change in the valuation allowance for the years ended May 31, 2021 and 2020 was an increase of $2,292,000 and $1,152,000, respectively. The Company increased the deferred tax asset and the valuation allowance by $437,000 as of May 31, 2020 based on the outstanding stock options as of May 31, 2020. This change had no impact on the Company’s consolidated financial statements as our deferred tax asset is fully offset by our valuation allowance. At May 31, 2021, the Company has Federal income tax net operating loss carryforwards of approximately $12,957,000. At May 31, 2021, the Company has California state income tax net operating loss carryforwards of approximately $6,768,000. For tax reporting purposes, operating loss carryforwards are available to offset future taxable income; such carryforwards expire in varying amounts beginning in 2022 and 2037 for federal and state purposes, respectively. Federal net operating losses beginning in 2018 have no expiration date. At May 31, 2021, the Company has Federal research and development tax credit carryforward of approximately $715,000. The Federal credits begin to expire in 2027. The Company also had similar credit carryforwards for state purposes of $341,000 at May 31, 2021, which don’t expire. Pursuant to Internal Revenue Code (“IRC”) Sections 382 and 383, annual use of the Company's net operating loss ("NOL") and credit carryforwards may be limited by statute because of a cumulative change in ownership of more than 50%. Pursuant to Sections 382 and 383 of the IRC, the annual use of the Company's NOLs and credit carryforwards would be limited if there is a cumulative change of ownership (as that term is defined in Section 382(g) of the IRC of greater than 50% in a three-year period. Management has not performed an analysis to determine if the Company has had a cumulative change in ownership of greater than 50%. For the year ended May 31, 2021, the Company did an analysis of its ASC 740 position and has not identified any uncertain tax positions as defined under ASC 740. Should such position be identified in the future and should the Company owe interest and penalties as a result of this, these would be recognized as interest expense and other expense, respectively, in the consolidated financial statements. The Company is no longer subject to any significant U.S. federal tax examinations by tax authorities for years before fiscal year 2017.

GEOGRAPHIC INFORMATION

GEOGRAPHIC INFORMATION	12 Months Ended
	May 31, 2021
Geographic Information Disclosure [Abstract]
Geographic Information Disclosure [Text Block]	NOTE 8: GEOGRAPHIC INFORMATION The Company operates as one segment. Geographic information regarding net sales is approximately as follows: Year Ended May 31, 2021 May 31, 2020 Revenues from sales to unaffiliated customers: Europe $ 4,301,000 60% $ 2,434,000 36% Asia 1,908,000 26% 1,867,000 28% United States 548,000 8% 445,000 7% South America 250,000 3% 1,615,000 24% Middle East 192,000 3% 314,000 5% Other - 0% 18,000 0% Total $ 7,199,000 100% $ 6,693,000 100%

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	May 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	NOTE 9: COMMITMENTS AND CONTINGENCIES OPERATING LEASES On June 18, 2009, the Company entered into an agreement to lease a building in Irvine, California. The lease commenced September 1, 2009 and ended August 31, 2016. On November 30, 2015, the Company entered into the First Amendment to Lease wherein it exercised its option to extend its lease until August 31, 2021. The initial base rent for the lease extension was $21,000 per month, increasing to $23,637 through August 31, 2021. On April 9, 2021 the Company exercised its second option to extend its lease for an additional five years through August 2026. The Company was also granted an additional five years lease extension option through August 2031. The rent is currently $23,637 per month and will increase on September 1, 2021 to $25,970 per month and be increased 3% each year thereafter. The security deposit of $22,080 remains the same. In November 2016, the Company’s subsidiary, Biomerica de Mexico, entered into a ten-year lease for approximately 8,104 square feet at a monthly rent of $2,926. The Company has one 10-year option to renew at the end of the initial lease period. The yearly rate is subject to an annual adjustment for inflation according to the United States Bureau of Labor Statistics Consumer Price Index for All Urban Consumers. The monthly rate is currently $3,262. Biomerica, Inc. is not a guarantor of such lease. Biomerica de Mexico also leases a smaller unit on a month-to-month basis for use in one manufacturing process. In addition, the Company leases a small office in Lindau, Germany on a month-to-month basis, as headquarters for BioEurope GmbH, its Germany subsidiary. Total gross rent expense in the U.S. for fiscal 2021 was $294,759 and 2020 was $300,267. Rent expense for the Mexico facility for fiscal 2021 and 2020 was $25,351 and $43,481, respectively. For purposes of determining straight-line rent expense, the lease term is calculated from the date the Company first takes possession of the facility, including any periods of free rent and any renewal options periods that the Company is reasonably certain of exercising. The Company’s office and equipment leases generally have contractually specified minimum rent and annual rent increases are included in the measurement of the right-of-use asset and related lease liability. Additionally, under these lease arrangements, the Company may be required to pay directly, or reimburse the lessors, for some maintenance and operating costs. Such amounts are generally variable and therefore not included in the measurement of the right-of-use asset and related lease liability but are instead recognized as variable lease expense in the Consolidated Statements of Operations and Comprehensive Loss when they are incurred. Supplemental cash flow information related to leases for the year ended May 31: 2021 2020 Operating cash flows from operating leases $ 320,606 $ 311,742 Right-of-use assets obtained in exchange for $ 79,159 $ - Weighted average remaining lease term (in years) 5.27 6.27 Weighted average discount rate 6.50% 6.50% Future minimum lease payments under the operating lease as of May 31, 2021 are as follows: 2022 $ 337,630 2023 350,311 2024 360,769 2025 371,539 2026 382,631 Thereafter 103,927 Total undiscounted lease payments 1,906,807 Less imputed interest 287,293 Total operating lease liabilities $ 1,619,514 According to the terms of the lease in Irvine, the Company is also responsible for routine repairs of the building and for certain increases in property tax. The Company also has various insignificant leases for office equipment. RETIREMENT SAVINGS PLAN Effective September 1, 1986, the Company established a 401(k) plan for the benefit of its employees. The plan permits eligible employees to contribute to the plan up to the maximum percentage of total annual compensation allowable under the limits of IRC Sections 415, 401(k) and 404. The Company, at the discretion of its Board of Directors, may make contributions to the plan in amounts determined by the Board each year. No contributions by the Company have been made since the plan's inception. LITIGATION The Company is, from time to time, involved in legal proceedings, claims and litigation arising in the ordinary course of business. While the amounts claimed may be substantial, the ultimate liability cannot presently be determined because of considerable uncertainties that exist. Therefore, it is possible the outcome of such legal proceedings, claims and litigation could have a material effect on quarterly or annual operating results or cash flows when resolved in a future period. However, based on facts currently available, management believes such matters will not have a material adverse effect on the Company's consolidated financial position, results of operations or cash flows. There were no legal proceedings pending as of May 31, 2021. On July 2, 2020, we received a notice of investigation and subpoena to produce information and documents from the Division of Enforcement of the SEC. The subpoena requested information and documents related to events and circumstances leading up to our March 17, 2020 announcement that we had commenced shipping samples of our COVID-19 IgG/IgM Rapid Test to countries outside of the United States, and had initiated the application process with the United States Food and Drug Administration under the COVID-19 Emergency Use Authorization for approval to market and sell the test in the United States. The subpoena also requested information and documents about the identity of any persons who were aware of the substance of the March 17, 2020 announcement prior to that date. In addition, on December 15, 2020, the SEC sent a second subpoena related to this investigation to Zack Irani, the Company’s CEO, requesting documents held by Mr. Irani concerning his past purchases of Company stock, his past communications with certain persons and entities, and other personal and Company documents. The Company and Mr. Irani have cooperated fully with the SEC’s investigation and provided information as requested. At this time, the Company is unable to predict the duration, scope or outcome of these investigations. CONTRACTS Contracts and Licensing Agreements The Company has one royalty agreement in which it has obtained rights to manufacture and market certain products for the life of the products. Royalty expense of approximately $11,000 and $15,000 is included in cost of sales for the agreement for each of the years ended May 31, 2021 and 2020, respectively. Sales of products manufactured under these agreements comprise approximately 1.5% and 1.8% of total sales for the years ended May 31, 2021 and 2020, respectively. The Company may license other products or technology in the future as it deems necessary for conducting business. The Company has other royalty agreements, however they are not considered material. On May 25, 2016, the Company entered into an Exclusive Marketing License Agreement (“Telcon Agreement”) with Celtis Pharm Co., Ltd., who subsequently changed their name to Telcon Pharmaceutical Co., LTD (“Telcon”), a medical company in South Korea. The Telcon Agreement grants to Telcon an exclusive license to market and sell Biomerica’s new InFoods® IBS products (“IBS Products”) in South Korea. The term of the agreement is for a period of five years following Korean FDA clearance of the product and provides an additional two years for Telcon to attain such Korean FDA clearance. The sequential two-year and five-year terms do not begin until after Biomerica first receives final clearance for sale of the IBS Products in the United States from the FDA. Telcon, at its sole cost and expense, must use its commercially reasonable good faith efforts to obtain Korean FDA for the IBS Product to be sold in South Korea. The agreement may be cancelled if Biomerica has not obtained final USFDA clearance for sale of the IBS Products on or before December 31, 2019. Biomerica is also obligated to maintain a full quality assurance system for the IBS Products following the harmonized standards according to Annex IV of Directive 98/79/EC. We are working with Telcon management to extend the term of the Telcon Agreement. The terms of the Telcon Agreement provide up to $1.25 million in exclusivity fees based on certain milestones including Biomerica’s starting clinical trials in the United States, receipt of U.S. FDA clearance and Telcon’s first sales of IBS Products in Korea. If Biomerica commences FDA Trials and Telcon pays the initial $250,000 milestone-based exclusivity fees, and the Agreement is subsequently terminated by either party for lack of performance, then Biomerica shall issue to Telcon 83,333 shares of Biomerica common stock in consideration for the $250,000 of paid exclusivity fee. No exclusivity fees have yet been paid. Additionally, the Telcon Agreement provides for a royalty of 15% paid to Biomerica on all sales in Korea of the IBS Product, and further sets the pricing of IBS Products sold to Telcon. In order to retain the exclusivity within South Korea, Telcon must meet certain annual minimum royalty payments to Biomerica following Telcon’s receipt of Korean FDA approval or clearance for the IBS Product to be sold in Korea, which in no case will be later than May 31, 2019. On May 29, 2019, the Company entered into an exclusive distribution agreement which contained certain annual minimum sales requirements, with MaxHealth Medical International Limited (a Chinese company) for the distribution of the Company’s EZ Detect Product in China. On March 15, 2021, the Company terminated this agreement due to MaxHealth’s failure to meet the minimum sales requirements. On April 1, 2020, the Company entered into two separate non-exclusive license agreements (the “Mount Sinai License Agreements”) with the Mount Sinai Icahn School of Medicine in New York (“Mount Sinai”) to license technology from Mount Sinai that the Company intends to use to scale up and manufacture a laboratory version serological test for SARS-CoV-2 coronavirus. This test uses the ELISA microplate format that can run on existing open system equipment found in most hospitals and clinical laboratories in the United States. The non-exclusive Mount Sinai License Agreements provide for royalty payments to Mount Sinai based on a percentage of gross sales of commercial products manufactured and sold by Biomerica that incorporate the Mount Sinai technology licensed under the Mount Sinai License Agreement. On June 20, 2020, the Company filed for Emergency Use Authorization with the FDA based on this on this technology. The Company purchased materials in the amount of $5,100 during fiscal 2020 and subsequently to that another $2,850. No royalty fees have been paid yet on these agreements. On May 7, 2020, the Company entered into an exclusive license agreement (the “UC License Agreements”) with The Regents of the University of California (“UC”) to license all patent rights pertaining to certain licensed technology from UC. This technology is being developed at the University by one of the professors and his team utilizing CRISPR technology. This group is developing a viral detection test for SARS-CoV-2 coronavirus. If this technology development is successful, the Company will work with the University to transfer the technology to Biomerica where the CRISPR based product will need to be further developed, validated and cleared with regulatory agencies for commercial sale into the market. The exclusive UC License Agreements provide for an initial and annual license fee, and a royalty payment on all commercial revenues, to the UC Regents. The UC License Agreement also includes certain investment requirements and milestones the Company will need to meet for the launch of a commercial product based on the licensed technology. The Company paid an initial license fee of $5,000 with the execution of the agreement. An additional $5,000 was paid in September 2020. No royalties have been paid yet on this agreement. A license maintenance fee of $10,000 is due annually. This is creditable against earned royalties due each year in the amount of five percent on net sales of licensed products. Clinical Trial Agreements In September 2017, the Company signed a Clinical Samples Agreement with the University of Southern California for the purpose of providing clinical samples for use by the Company in conducting future clinical trials for one of the products which the Company is developing. The initial budget was estimated to be $82,472. The work started in October 2017 with charges for work performed being invoiced and paid monthly. This study ended in February 2020. The Company incurred $2,200 in fiscal 2020 and $12,567 in expenses previously invoiced for a total of $14,767. In addition, $17,064 in fees has been accrued for unbilled charges as of May 31, 2021. In November 2017, the Company entered into a Clinical Trial Agreement with the University of Michigan to perform an InFoods ® 24 Endpoint Determination Study. The Company will be invoiced monthly for work performed the previous month. The maximum budget for the study is $181,015. The Company incurred $20,550 and $30,900 in expenses for this study during fiscal 2021 and 2020, respectively. This commitment is approximately 56% billed. The Company has accrued $2,050 in charges as of May 31, 2021. In January 2018, the Company entered into a Clinical Trial Agreement with Beth Israel Deaconess Medical Center for the purposes of conducting an Antibody Guided Restriction Trial Using Biomerica InFoods ® 24G Test in patients with a previous diagnosis of Irritable Bowel Syndrome. The study began in the first quarter of fiscal 2019. The Company was invoiced monthly for work performed the previous month. The total cost of the study was initially estimated to be $142,000, however the study was expanded and total costs of the trial was approximately $305,000. The Company incurred $0 and $141,640 in expenses for this study during fiscal 2021 and 2020, respectively. This study was closed in February 2020 and no additional costs are expected. On July 12, 2019, the Company entered into a Clinical Trial Agreement with a research management institution for the purpose of conducting a clinical trial of the Biomerica HP Stool Antigen test. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs were approximately $117,200. During fiscal 2021 and 2020, $13,111 and $13,355 in charges were billed, respectively. This study is now closed so no further charges will be incurred. On July 22, 2019, the Company entered into a Clinical Trial Agreement with a research institution, for the purpose of conducting a clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be approximately $107,000. The Company incurred $20,875 in charges during fiscal 2020. This commitment is approximately 31% billed. In addition, the Company was billed $12,675 in fiscal 2021 and accrued $19,600 in unbilled charges as of May 31, 2021. On September 25, 2019, the Company entered into a Clinical Trial Agreement with a medical practice for the purpose of conducting a clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be $136,000. During fiscal 2021 and 2020, the Company was invoiced $11,725 and $45,250 respectively in expenses. This commitment is approximately 42% billed. In addition, the Company accrued $5,975 in unbilled charges as of May 31, 2020. No charges were accrued at May 31, 2021. On September 25, 2019, the Company entered into a Clinical Trial Agreement with a research institution for the purpose of conducting a clinical trial of the Biomerica H. pylori product. The term of the agreement shall be until completion of the work outlined and the charges were invoiced monthly for work performed in the previous month. The maximum budgeted costs will be approximately $57,800. The Company was invoiced $41,845 in charges during the year ended May 31, 2020. At May 31, 2020, the commitment was approximately 72% billed and the study was closed so no further charges will be incurred. In December 2019, the Company entered into a Clinical Trial Agreement with Houston Methodist Research Institute for the purpose of conducting a clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be approximately $133,000. During the years ended May 31, 2021 and 2020, the Company was invoiced $0 and $4,000 in charges, respectively. This commitment is approximately 3% billed. The Company accrued $3,550 in charges at May 31, 2021. On May 28, 2020, the Company entered into a Clinical Trial Agreement with the Mayo Clinic Arizona for the purpose of participating in the ongoing end point clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be $135,515. At May 31, 2021 and 2020, $0 and $17,390 had been invoiced to the Company. The Company has accrued $3,750 in expenses as of May 31, 2021. This commitment is approximately 13% billed. On May 28, 2020, the Company entered into a Clinical Trial Agreement with the Mayo Clinic Jacksonville for the purpose of participating in the ongoing end point clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be $135,515. The Company has not received any billings as of May 31, 2020, however accrued $17,390 in charges as of that date. The Company received $22,827 in billings in fiscal 2021 and did not accrue any charges as of May 31, 2021. As of May 31, 2021, approximately 17% of the commitment had been invoiced. On June 25, 2020, the Company entered into a Clinical Trial Agreement with the University of Texas Health Science Center for the purpose of conducting a clinical trial of the Biomerica InFoods® product. The term of the agreement shall be until completion of the work outlined and the charges will be invoiced monthly for work performed in the previous month. The maximum budgeted costs will be $139,850. As of May 31, 2021, $4,850 had been billed and $3,750 in accruals remained. As of May 31, 2021, approximately 4% of the commitment had been invoiced. The addition of both Mayo Clinic sites and other major medical centers were brought into the InFoods® IBS clinicals studies in order to accelerate patient enrollment.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	May 31, 2021
Subsequent Events [Abstract]
Subsequent Events [Text Block]	NOTE 10: SUBSEQUENT EVENTS Subsequent to May 31, 2021, as of the filing of the Original Form 10-K, options to purchase 1,500 shares of Biomerica common stock were exercised at the exercise price of $2.68 per share. Proceeds to the Company were approximately $4,000. Subsequent to May 31, 2021, as of the filing of the Original Form 10-K, the Company sold 201,553 shares of its common stock under its Form S-3 “shelf” Registration statement. The average sale price was $4.16 per share. Net proceeds to the Company were approximately $824,000. On June 21, 2021, the Company signed an exclusive distribution and marketing agreement in Canada for its Helicobacter Pylori (H. Pylori) test. In June 2021, the Company received a patent in Japan (#6902526) for the System and Method for a Digital Health System Providing a Food Recommendation Based on Food Sensitivity Testing. This technology is designed to allow for easier implementation of the dietary restrictions that result from InFoods® diagnostic testing. This method describes using a smartphone or similar technology to identify prepared or packaged foods that contain restricted food ingredients, using barcodes or product labels. In August 2021, the Company received a notice of allowance for a patent in Japan whose claims cover the use of the InFoods® technology to diagnose and treat depression, and covers the compositions, devices and methods of depression sensitivity testing.

RESTATEMENT OF PREVIOUSLY ISSUE

RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS	12 Months Ended
	May 31, 2021
Prior Period Adjustment [Abstract]
Error Correction [Text Block]	NOTE 11: RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS Subsequent to the issuance of our Form 10-K annual report, for the fiscal year ended May 31, 2021, which was filed on August 27, 2021, the Company determined that errors were included in the report as described below. As a result, this Form 10-K/A includes restated financial statements for the fiscal years ended May 31, 2021 and 2020. While reviewing the Company’s methodology used to calculate and report non-cash stock-based compensation expense, the Company discovered the errors listed below. The Company notified its independent registered accounting firm (“Auditors”) of the errors. Together, the Company and their Auditors have determined that these restatements correct the previously reported errors. Our non-cash stock based compensation expenses calculation applied forfeiture adjustments to both vested and unvested outstanding options, including those for which the employee had provided the requisite service, which resulted in an understatement of stock compensation expense. Additionally, our calculation expensed the option at vesting dates versus pro rata over the period the requisite service was provided. Stock-based compensation expense shown on the statement of operations is a non-cash expense, and impacts accumulated deficit and additional paid-in capital on the balance sheet. However, this does not impact the Company’s cash, revenues or other aspects of ongoing operations. The cumulative effect of this error on the Company's accumulated deficit as of May 31, 2019 was to increase the accumulated deficit by $836,232 from ($19,586,678) as originally filed, to ($20,422,910) and to increase the additional paid in capital by $836,232 from $22,830,006 as originally filed, to $23,666,238. The restatements for the years ended May 31, 2021 and 2020 resulted in no changes in the provision for income taxes. The effect of the restatement on the consolidated balance sheet at May 31, 2021 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 36,685,176 $ 2,151,567 $ 38,836,743 Accumulated deficit (28,394,768) (2,151,567) (30,546,335) Other Equity accounts 936,615 - 936,615 Total Shareholders' Equity $ 9,227,023 $ - $ 9,227,023 The effect of the restatement on the consolidated balance sheet at May 31, 2020 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,213,707 $ 1,174,349 $ 36,388,056 Accumulated deficit (21,925,732) (1,174,349) (23,100,081) Other Equity accounts 925,078 - 925,078 Total Shareholders' Equity $ 14,213,053 $ - $ 14,213,053 The effect of the restatement on the consolidated balance sheet at May 31, 2019 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 22,830,006 $ 836,232 $ 23,666,238 Accumulated deficit (19,586,678) (836,232) (20,422,910) Other Equity accounts 737,642 - 737,642 Total Shareholders' Equity $ 3,980,970 $ - $ 3,980,970 The effect of the restatement on the consolidated statement of operations for the year ended May 31, 2021 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 6,702,046 $ 130,696 $ 6,832,742 Gross Profit 496,981 (130,696) 366,285 Operating Expenses: Selling, general and administrative 4,608,950 785,575 5,394,525 Research and development 2,410,506 60,947 2,471,453 Total operating expense 7,019,456 846,522 7,865,978 Loss from operations (6,522,475) (977,218) (7,499,693) Loss before income taxes (6,455,979) (977,218) (7,433,197) Net loss $ (6,469,036) $ (977,218) $ (7,446,254) Basic net loss per common share $ (0.54) $ (0.08) $ (0.62) Diluted net loss per common share $ (0.54) $ (0.08) $ (0.62) Comprehensive loss $ (6,477,151) $ (977,218) $ (7,454,369) The effect of the restatement on the consolidated statement of operations for the year ended May 31, 2020 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 4,910,935 $ 43,549 $ 4,954,484 Gross Profit 1,781,776 (43,549) 1,738,227 Operating Expenses: Selling, general and administrative 2,274,415 272,207 2,546,622 Research and development 1,910,209 22,361 1,932,570 Total operating expense 4,184,624 294,568 4,479,192 Loss from operations (2,402,848) (338,117) (2,740,965) Loss before income taxes (2,331,664) (338,117) (2,669,781) Net loss $ (2,339,054) $ (338,117) $ (2,677,171) Basic net loss per common share $ (0.23) $ (0.03) $ (0.26) Diluted net loss per common share $ (0.23) $ (0.03) $ (0.26) Comprehensive loss $ (2,342,364) $ (338,117) $ (2,680,481) The effect of the restatement on the consolidated statement of cash flows for the year ended May 31, 2021 is as follows: As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (6,469,036) $ (977,218) $ (7,446,254) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 377,391 977,218 1,354,609 Net cash used in operating activities (5,251,748) - (5,251,748) Cash and cash equivalents at end of year $ 4,199,311 $ - $ 4,199,311 The effect of the restatement on the consolidated statement of cash flows for the year ended May 31, 2020 is as follows: As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (2,339,054) $ (338,117) $ (2,677,171) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 200,470 338,117 538,587 Net cash used in operating activities (4,297,498) - (4,297,498) Cash and cash equivalents at end of year $ 8,641,027 $ - $ 8,641,027 As a result of the restatement described above, the following adjustments are made to the previously filed quarterly results for the periods ended August 31, 2020, November 30, 2020 and February 28, 2021: The effect of the restatement on the consolidated balance sheet at August 31, 2020 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,231,415 $ 1,417,328 $ 36,648,743 Accumulated deficit (23,575,147) (1,417,328) (24,992,475) Other Equity accounts 924,357 - 924,357 Total Shareholders' Equity $ 12,580,625 $ - $ 12,580,625 The effect of the restatement on the consolidated statement of operations for the three months ended August 31, 2020 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 960,930 $ 64,787 $ 1,025,717 Gross Profit 182,876 (64,787) 118,089 Operating Expenses: Selling, general and administrative 1,164,564 141,380 1,305,944 Research and development 674,693 36,812 711,505 Total operating expense 1,839,257 178,192 2,017,449 Loss from operations (1,656,381) (242,979) (1,899,360) Loss before income taxes (1,648,290) (242,979) (1,891,269) Net loss $ (1,649,415) $ (242,979) $ (1,892,394) Basic net loss per common share $ (0.14) $ (0.02) $ (0.16) Diluted net loss per common share $ (0.14) $ (0.02) $ (0.16) Comprehensive loss $ (1,651,136) $ (242,979) $ (1,894,115) The effect of the restatement on the consolidated statement of cash flows for the three months ended August 31, 2020 is as follows: As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (1,649,415) $ (242,979) $ (1,892,394) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 3,808 242,979 246,787 Net cash used in operating activities (1,597,146) - (1,597,146) Cash and cash equivalents at end of period $ 6,964,314 $ - $ 6,964,314 The effect of the restatement on the consolidated balance sheet at November 30, 2020 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,284,864 $ 1,650,262 $ 36,935,126 Accumulated deficit (25,060,311) (1,650,262) (26,710,573) Other Equity accounts 924,228 - 924,228 Total Shareholders' Equity $ 11,148,781 $ - $ 11,148,781 The effect of the restatement on the consolidated statement of operations for the six months ended November 30, 2020 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 1,971,960 $ 117,564 $ 2,089,524 Gross Profit 544,372 (117,564) 426,808 Operating Expenses: Selling, general and administrative 2,419,411 291,379 2,710,790 Research and development 1,261,096 66,970 1,328,066 Total operating expense 3,680,507 358,349 4,038,856 Loss from operations (3,136,135) (475,913) (3,612,048) Loss before income taxes (3,120,061) (475,913) (3,595,974) Net loss $ (3,134,579) $ (475,913) $ (3,610,492) Basic net loss per common share $ (0.27) $ (0.04) $ (0.31) Diluted net loss per common share $ (0.27) $ (0.04) $ (0.31) Comprehensive loss $ (3,137,829) $ (475,913) $ (3,613,742) The effect of the restatement on the consolidated statement of operations for the three months ended November 30, 2020 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 1,011,030 $ 52,777 $ 1,063,807 Gross Profit 361,496 (52,777) 308,719 Operating Expenses: Selling, general and administrative 1,254,847 149,999 1,404,846 Research and development 586,403 30,158 616,561 Total operating expense 1,841,250 180,157 2,021,407 Loss from operations (1,479,754) (232,934) (1,712,688) Loss before income taxes (1,471,771) (232,934) (1,704,705) Net loss $ (1,485,164) $ (232,934) $ (1,718,098) Basic net loss per common share $ (0.13) $ (0.02) $ (0.15) Diluted net loss per common share $ (0.13) $ (0.02) $ (0.15) Comprehensive loss $ (1,486,694) $ (232,934) $ (1,719,628) The effect of the restatement on the consolidated statement of cash flows for the six months ended November 30, 2020 is as follows: As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (3,134,579) $ (475,913) $ (3,610,492) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 24,227 475,913 500,140 Net cash used in operating activities (2,880,218) - (2,880,218) Cash and cash equivalents at end of period $ 5,683,787 $ - $ 5,683,787 The effect of the restatement on the consolidated balance sheet at February 28, 2021 is as follows: As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 36,563,562 $ 1,935,493 $ 38,499,055 Accumulated deficit (26,899,621) (1,935,493) (28,835,114) Other Equity accounts 935,642 - 935,642 Total Shareholders' Equity $ 10,599,583 $ - $ 10,599,583 The effect of the restatement on the consolidated statement of operations for the nine months ended February 28, 2021 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 5,639,103 $ 152,490 $ 5,791,593 Gross Profit 505,867 (152,490) 353,377 Operating Expenses: Selling, general and administrative 3,697,804 540,933 4,238,737 Research and development 1,824,312 67,721 1,892,033 Total operating expense 5,522,116 608,654 6,130,770 Loss from operations (5,016,249) (761,144) (5,777,393) Loss before income taxes (4,962,488) (761,144) (5,723,632) Net loss $ (4,973,889) $ (761,144) $ (5,735,033) Basic net loss per common share $ (0.42) $ (0.07) $ (0.49) Diluted net loss per common share $ (0.42) $ (0.07) $ (0.49) Comprehensive loss $ (4,982,576) $ (761,144) $ (5,743,720) The effect of the restatement on the consolidated statement of operations for the three months ended February 28, 2021 is as follows: As Previously Reported Adjustments As Restated Cost of sales $ 3,667,143 $ 34,926 $ 3,702,069 Gross Loss (38,505) (34,926) (73,431) Operating Expenses: Selling, general and administrative 1,278,393 249,554 1,527,947 Research and development 563,216 751 563,967 Total operating expense 1,841,609 250,305 2,091,914 Loss from operations (1,880,114) (285,231) (2,165,345) Loss before income taxes (1,842,427) (285,231) (2,127,658) Net loss $ (1,839,310) $ (285,231) $ (2,124,541) Basic net loss per common share $ (0.15) $ (0.03) $ (0.18) Diluted net loss per common share $ (0.15) $ (0.03) $ (0.18) Comprehensive loss $ (1,844,747) $ (285,231) $ (2,129,978) The effect of the restatement on the consolidated statement of cash flows for the nine months ended February 28, 2021 is as follows: As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (4,973,889) $ (761,144) $ (5,735,033) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 261,176 761,144 1,022,320 Net cash used in operating activities (4,244,064) - (4,244,064) Cash and cash equivalents at end of period $ 5,272,565 $ - $ 5,272,565

Accounting Policies, by Policy

Accounting Policies, by Policy (Policies)	12 Months Ended
	May 31, 2021
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	PRINCIPLES OF CONSOLIDATION The enclosed consolidated financial statements for the years ended May 31, 2021 and 2020 include the accounts of Biomerica, Inc. ("Biomerica") as well as its German subsidiary (BioEurope GmbH) and Mexican subsidiary (Biomerica de Mexico). All significant intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates, Policy [Policy Text Block]	ACCOUNTING ESTIMATES The preparation of the consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reported period. Estimates that are made include the allowance for doubtful accounts, which is estimated based on current as well as historical past practices with a customer; stock option forfeiture rates, which are calculated based on historical data; inventory obsolescence, which are based on projected and historical usage of materials; and lease liability and right-of-use assets, which are calculated based on certain assumptions such as borrowing rate, the likelihood of lease extensions to occur, asset valuation, among other things; and other items that may be necessary to estimate using current, historical and judgment based information. Actual results could materially differ from those estimates.
Markets And Methods Of Distribution [Policy Text Block]	MARKETS AND METHODS OF DISTRIBUTION Due to the Coronavirus global pandemic, the Company’s operations have been negatively impacted. The Company has faced disruptions in certain of the following areas, and may face further challenges from supply chain disruptions, loss of contracts and/or customers, closure of the Company’s manufacturing or distribution facilities or of the facilities of the Company’s suppliers, partners and customers, travel, shipping and logistical disruptions, government responses of all types, international business risks in countries where the Company makes and/or sells its products, loss of human capital or personnel at the Company, its partners and its customers, interruptions of production, customer credit risk, and general economic calamities. These ongoing pandemic related disruptions can materially negatively impact the Company’s operations and financial performance and may continue to have significant material negative impacts on the Company.
Liquidity [Policy Text Block]	LIQUIDITY The Company has incurred net losses and negative cash flows from operations and has an accumulated deficit of approximately $30.5 million as of May 31, 2021. Management expects to continue to incur significant costs as it advances its trials and development activities. On January 22, 2021, the Company filed a Prospectus Supplement for purposes of raising up to $15,000,000 to the base prospectus filed with the SEC on July 21, 2020 and declared effective by the SEC on September 30, 2020 and an ATM Agreement. The Company intends to use the net proceeds from such offering for general corporate purposes, including, without limitation, sales and marketing activities, clinical studies and product development, making acquisitions of assets, businesses, companies or securities, capital expenditures, and for working capital needs. Under an ATM Agreement, sales of the Placement Shares are deemed to be “at the market offering” as defined in Rule 415 promulgated under the Securities Act. The agent acts as sales agent under the ATM and uses commercially reasonable efforts to sell on the Company’s behalf all of the Placement Shares requested to be sold from time to time by the Company, consistent with its normal trading and sales practices, on mutually agreed terms between the agent and the Company. The Company has no obligation to sell any of the Placement Shares under the ATM Agreement, and may at any time suspend offers under, or terminate the ATM Agreement. During the year ended May 31, 2021, the Company sold 158,889 shares of its common stock at prices ranging from $7.06 to $7.79 under its Form S-3 Registration Statement ( File No. 333-239980) and ATM Agreement which resulted in gross proceeds of $1,177,394 and net proceeds to the Company of $1,011,475 after deducting commissions for each sale and legal, accounting and other fees related to the filing of the Form S-3. As a result of cash and cash equivalents on hand at May 31, 2021, management believes the Company has sufficient funds to operate through August 2022 and the ability to raise additional funds through the ATM noted above.
Fair Value Measurement, Policy [Policy Text Block]	FAIR VALUE OF FINANCIAL INSTRUMENTS The Company has financial instruments whereby the fair market value of the financial instruments could be different than that recorded on a historical basis. The Company's financial instruments consist of its cash and cash equivalents, accounts receivable, and accounts payable. The carrying amounts of the Company's financial instruments approximate their fair values.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	CONCENTRATION OF CREDIT RISK The Company maintains cash balances at certain financial institutions in excess of amounts insured by federal agencies. As of May 31, 2021, the Company had approximately $3,767,000 of uninsured cash. The Company does not believe it is exposed to any significant credit risks. The Company provides credit in the normal course of business to customers throughout the United States and in foreign markets. The Company performs ongoing credit evaluations of its customers and requires accelerated prepayment in some circumstances. For the years ended May 31, 2021 and 2020, the Company had two distributors and three distributors which accounted for a total of 60% and 57% of our net consolidated sales, respectively. Of this, for the years ended May 31, 2021 and 2020 one of the distributors mentioned above accounted for 33% and 26%, respectively, of net consolidated sales. At May 31, 2021 and 2020, the Company had two distributors and three distributors which accounted for a total of 73% and 80%, respectively, of gross accounts receivable. $2,292,466 and $1,836,852, respectively. For the year ended May 31, 2021, one vendor accounted for 58% of the purchases of raw materials. For the year ended May 31, 2020, one vendor accounted for a total of 59% of the purchases of raw materials.
Concentration Risk Geographic Policy [Policy Text Block]	GEOGRAPHIC CONCENTRATION As of May 31, 2021 and 2020, approximately $803,000 and $613,000 of Biomerica's gross inventory and approximately $25,000 and $31,000, of Biomerica's property and equipment, net of accumulated depreciation, was located in Mexicali, Mexico, respectively.
Cash and Cash Equivalents, Policy [Policy Text Block]	CASH AND CASH EQUIVALENTS Cash and cash equivalents consist of demand deposits and money market accounts with original maturities of less than three months.
Accounts Receivable [Policy Text Block]	ACCOUNTS RECEIVABLE The Company extends unsecured credit to its customers on a regular basis. International accounts are usually required to prepay until they establish a history with the Company and at that time, they are extended credit at levels based on a number of criteria. Based on various criteria, initial credit levels for individual distributors are approved by designated officers and managers of the Company. All increases in credit limits are also approved by designated upper-level management. Management evaluates receivables on a quarterly basis and adjusts the allowance for doubtful accounts accordingly. Balances over ninety days old are usually reserved for unless collection is reasonably assured. Occasionally certain long-standing customers, who routinely place large orders, will have unusually large receivables balances relative to the total gross receivables. Management monitors the payments for these large balances closely and very often requires payment of existing invoices before shipping new sales orders. The Company has established a reserve of $837,415 for doubtful accounts as of May 31, 2021. The majority of this reserve has been established to cover 100% of outstanding accounts receivable from an international distributor.
Prepaids Policy [Policy Text Block]	PREPAIDS The Company occasionally prepays for items such as inventory, insurance and other items. These items are reported as prepaids, until either the inventory is physically received or the insurance and other items are utilized. As of May 31, 2021, the prepaids were approximately $370,000, composed of prepayments to insurance and various other suppliers. As of May 31, 2020, approximately $1 million of the prepaids was an advance payment to one of our suppliers, which was subsequently refunded by the supplier when the Company determined it no longer needed the materials that had been ordered.
Inventory, Policy [Policy Text Block]	INVENTORIES, NET The Company values inventory at the lower of cost (determined using a combination of specific lot identification and the first-in, first-out methods) or net realizable value. Management periodically reviews inventory for excess quantities and obsolescence. Management evaluates quantities on hand, physical condition, and technical functionality as these characteristics may be impacted by anticipated customer demand for current products and new product introductions. The reserve is adjusted based on such evaluation, with a corresponding provision included in cost of sales. Abnormal amounts of idle facility expenses, freight, handling costs and wasted material are recognized as current period charges and the allocation of fixed production overhead is based on the normal capacity of the production facilities. Inventories approximate the following at May 31: May 31, 2021 May 31, 2020 Raw materials $ 1,583,000 $ 1,635,000 Work in progress 1,006,000 988,000 Finished products 617,000 228,000 Total $ 3,206,000 $ 2,851,000 Reserves for inventory obsolescence are recorded as necessary to reduce obsolete inventory to estimated net realizable value or to specifically reserve for obsolete inventory that the Company intends to dispose of. As of May 31, 2021 and 2020, inventory reserves were approximately $1,617,000 and $67,000, respectively. Of the inventory reserve, $1,502,675 was related to a market downturn in our COVID-19 antibody test and materials, as the market shifted to COVID-19 PCR viral tests and antigen tests.
Property, Plant and Equipment, Policy [Policy Text Block]	PROPERTY AND EQUIPMENT, NET Property and equipment are stated at cost. Expenditures for additions and major improvements are capitalized. Repairs and maintenance costs are charged to operations as incurred. When property and equipment are sold, retired or otherwise disposed of, the related cost and accumulated depreciation or amortization are removed from the accounts, and gains or losses from sales, retirements and dispositions are credited or charged to income. Depreciation and amortization are provided over the estimated useful lives of the related assets, ranging from 5 to 10 years, using the straight-line method. Leasehold improvements are amortized over the lesser of the estimated useful life of the asset or the term of the lease. Depreciation and amortization expense on property and equipment amounted to $104,715 and $105,299 for the years ended May 31, 2021 and 2020, respectively.
Goodwill and Intangible Assets, Policy [Policy Text Block]	INTANGIBLE ASSETS, NET Intangible assets include trademarks, product rights, technology rights and patents, and are accounted for based on Accounting Standards Codification (“ASC”), ASC 350 Intangibles – Goodwill and Other (“ASC 350”). In that regard, intangible assets that have indefinite useful lives are not amortized but are tested at least annually for impairment or more frequently if events or changes in circumstances indicate that the asset might be impaired. Intangible assets are being amortized using the straight-line method over the useful life, not to exceed 18 years for marketing and distribution rights, 10 years for purchased technology use rights, and 20 years for patents. Amortization amounted to $33,552 and $23,873 for the years ended May 31, 2021 and 2020, respectively. The Company assesses the recoverability of these intangible assets by determining whether the amortization of the asset's balance over its remaining life can be recovered through projected undiscounted future cash flows. The Company uses a qualitative assessment to determine whether there was any impairment. No impairment adjustment was required as of May 31, 2021 or 2020.
Investment, Policy [Policy Text Block]	INVESTMENTS From time-to-time, the Company makes investments in privately-held companies. The Company determines whether the fair values of any investments in privately-held entities have declined below their carrying value whenever adverse events or changes in circumstances indicate that recorded values may not be recoverable. If the Company considers any such decline to be other than temporary (based on various factors, including historical financial results, and the overall health of the investee’s industry), a write-down to estimated fair value is recorded. Investments represent the Company’s investment in a Polish distributor which is primarily engaged in distributing medical products and devices. The Company currently has not written down the investment and no events have occurred which could indicate the carrying value of the investment to be greater than the fair value. The Company owns approximately 6% of the investee and, accordingly, applies the cost method to account for the investment. Under the cost method, investments are recorded at cost, with gains and losses recognized as of the sale date, and income recorded when received.
Share-based Payment Arrangement [Policy Text Block]	SHARE-BASED COMPENSATION The Company follows the guidance of the accounting provisions of ASC 718 The grant date fair value of the award is recognized under the straight-line attribution method. In applying the Black-Scholes options-pricing model, assumptions used were as follows: 2021 2020 Dividend yield 0% 0% Expected volatility 71.19-107.53% 55.52-72.62% Risk free interest rate 0.34-1.18% 0.43-1.80% Expected Term 5.50-6.25 Years 3.75-6.25 Years
Revenue [Policy Text Block]	REVENUE RECOGNITION The Company has various contracts with customers. All of the contracts specify that revenues from product sales are recognized at the time the product is shipped, customarily FOB shipping point, which is when the transfer of control of goods has occurred and at which point title passes. The Company does not allow for returns except in the event of defective merchandise and therefore does not establish an allowance for returns. In addition, the Company has contracts with customers wherein they receive purchase discounts for achieving specified sales volumes. The Company evaluated the status of these contracts as of May 31, 2021 and 2020 and does not believe that any additional discounts will be given through the end of the contract periods. Services for some contract work are invoiced and recognized for work that has been performed as the project progresses. The Company sells clinical lab products to domestic and international distributors, including hospitals and clinical laboratories, medical research institutions, medical schools and pharmaceutical companies. OTC products are sold directly to drug stores and e-commerce customers as well as to distributors. Physicians’ office products are sold to physicians and distributors, all of whom are categorized below according to the type of products sold to them. We also manufacture certain components on a contract basis for domestic and international manufacturers. Disaggregation of revenue: The following is a breakdown of revenues according to markets to which the products are sold: Year Ended May 31, 2021 May 31, 2020 Clinical lab $ 3,077,000 $ 2,922,000 Physician's office 2,801,000 2,195,000 Over-the-counter 766,000 1,270,000 Contract manufacturing 552,000 306,000 Lab supplies 3,000 - Total $ 7,199,000 $ 6,693,000 See Note 8 for additional information regarding revenue concentrations.
Cost of Goods and Service [Policy Text Block]	SHIPPING AND HANDLING FEES The Company includes shipping and handling fees billed to customers in net sales.
Research and Development Expense, Policy [Policy Text Block]	RESEARCH AND DEVELOPMENT Research and development costs are expensed as incurred. The Company expensed $2,471,453 and $1,932,570 of research and development costs during the years ended May 31, 2021 and 2020, respectively.
Income Tax, Policy [Policy Text Block]	INCOME TAXES The Company accounts for income taxes in accordance with ASC 740, Income Taxes (“ASC 740”). Deferred tax assets and liabilities arise from temporary differences between the tax bases of assets and liabilities and their reported amounts in the consolidated financial statements that will result in taxable or deductible amounts in future years and the benefits of net operating loss and tax credit carryforwards. These temporary differences and the benefits of net operating loss and tax credit carryforwards are measured using enacted tax rates. A valuation allowance is recorded to reduce deferred tax assets to the extent that management considers it is more likely than not that a deferred tax asset will not be realized. In determining the valuation allowance, the Company considers factors such as the reversal of deferred income tax assets, projected taxable income, and the character of income tax assets and tax planning strategies. A change to these factors could impact the estimated valuation allowance and income tax expense. At May 31, 2021 and 2020, in accordance with ASC 740, the Company has a valuation allowance for substantially all of its deferred tax assets. During the fiscal year ended May 31, 2021, this valuation allowance was increased to $5,904,000, which fully covers the tax asset of $5,904,000 . The Company accounts for its uncertain tax provisions by using a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not, based solely on the technical merits, that the position will be sustained in an audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the appropriate amount of the benefit to recognize. The amount of benefit to recognize is measured as the maximum amount which is more likely than not to be realized. The tax position is derecognized when it is no longer more likely than not capable of being sustained. On subsequent recognition and measurement the maximum amount which is more likely than not to be recognized at each reporting date will represent the Company’s best estimate, given the information available at the reporting date, although the outcome of the tax position is not absolute or final. Upon adopting the revisions in ASC 740, the Company elected to follow an accounting policy to classify accrued interest related to liabilities for income taxes within the “Interest expense” line and penalties related to liabilities for income taxes within the “Other expense” line of the consolidated statements of operations and comprehensive loss.
Advertising Cost [Policy Text Block]	ADVERTISING COSTS The Company reports the cost of all advertising as expense in the period in which those costs are incurred. Advertising costs were approximately $10,070 174
Foreign Currency Transactions and Translations Policy [Policy Text Block]	FOREIGN CURRENCY TRANSLATION The subsidiary located in Mexico operates primarily using the Mexican peso. The subsidiary located in Germany operates primarily using the U.S. dollar, with an immaterial amount of transactions occurring using the Euro. Accordingly, assets and liabilities of these subsidiaries are translated using exchange rates in effect at the end of the year, and revenues and costs are translated using average exchange rates for the year. The resulting adjustments to assets and liabilities are presented as a separate component of accumulated other comprehensive loss. There are no adjustments to foreign currency loss that are included in the consolidated statements of operations for the years ended May 31, 2021 and 2020.
Lessee, Leases [Policy Text Block]	RIGHT-OF-USE ASSETS AND LEASE LIABILITY Incentive payments received from landlords are recorded as deferred lease incentives and are amortized over the underlying lease term on a straight-line basis as a reduction of rent expense. When the terms of an operating lease provide for periods of free rent, rent concessions, and/or rent escalations, the Company establishes a deferred rent liability for the difference between the scheduled rent payment and the straight-line rent expense recognized. This deferred rent liability was amortized over the underlying lease term on a straight-line basis as a reduction of rent expense. During the year ended May 31, 2020, the Company adopted ASC 842, Leases. As a result, the existing deferred rent liability was netted against the Right-of-Use Asset which was capitalized at that time. In February 2016, the Financial Accounting Standards Board (“FASB”) issued an accounting standards update which requires lessees to recognize most leases on the balance sheet with a corresponding right-of-use asset. Right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-Use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of fixed lease payments over the lease term. Leases are classified as financing or operating which will drive the expense recognition pattern. The Company has elected to exclude short-term leases. The Company adopted this guidance as of June 1, 2019, the required effective date, using the effective date transition method. An adjustment to opening accumulated deficit was not required in conjunction with adoption. The adoption of this statement resulted in a right-of-use asset being recorded in the amount of $1,942,999 and a lease liability being recorded in the amount of $1,980,970. On April 9, 2021, the Company exercised its second option to extend its lease for an additional five years. As part of that lease extension agreement, the Company was granted an additional right to extend its lease for five years, up through August 2031. However, given the recent growth in the Company’s operations, and the expectation that operations will continue to grow in the near future, the Company believes that it will be necessary to relocate into larger facilities by the end of the current lease term. Therefore, the Company has elected to not book the additional five-year extension option, from August 2026 to August 2031, into its right-of-use asset or its lease liability accounts. For additional information, see Note 9-Commitments and Contingencies. The Company has elected not to reassess whether expired or existing contracts contain leases, or reassess the classification of existing leases as of the adoption date. The Company leases office space and copy machines, all of which are operating leases. Most leases include the option to renew and the exercise of the renewal options is at the Company’s sole discretion. Options to extend or terminate a lease are considered in the lease term to the extent that the option is reasonably certain of exercise. The leases do not include the options to purchase the leased property. The depreciable life of assets and leasehold improvements are limited by the expected lease term.
Earnings Per Share, Policy [Policy Text Block]	NET LOSS PER SHARE Basic loss per share is computed as net loss divided by the weighted average number of common shares outstanding for the period. Diluted loss per share reflects the potential dilution that could occur from common shares issuable through stock options, warrants and other convertible securities using the treasury stock method. The total amounts of anti-dilutive stock options not included in the loss per share calculation for the years ended May 31, 2021 and 2020 were 2,081,366 and 1,789,251, respectively. The Company also had 0 and 321,429 of Series A 5% Convertible Preferred Stock outstanding for the years ended May 31, 2021 and 2020, respectively. The 321,429 shares outstanding at May 31, 2020 were converted to common stock during the year ended May 31, 2021.
Segment Reporting, Policy [Policy Text Block]	SEGMENT REPORTING ASC 280, Segment Reporting (“ASC 280”), establishes standards for reporting, by public business enterprises, information about operating segments, products and services, geographic areas, and major customers. The Company’s operations are analyzed by management and its chief operating decision maker as being part of a single industry segment: the design, development, marketing and sales of diagnostic kits.
Comprehensive Income, Policy [Policy Text Block]	REPORTING COMPREHENSIVE LOSS Comprehensive loss represents net loss and any revenues, expenses, gains and losses that, under GAAP, are excluded from net loss and recognized directly as a component of shareholders’ equity. Accumulated other comprehensive loss consists solely of foreign currency translation adjustments.
New Accounting Pronouncements, Policy [Policy Text Block]	RECENT ACCOUNTING PRONOUNCEMENTS Recent ASU's issued by the FASB and guidance issued by the SEC did not, or are not believed by management to, have a material effect on the Company’s present or future consolidated financial statements.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	May 31, 2021
Accounting Policies [Abstract]
Schedule of Inventory, Current [Table Text Block]	May 31, 2021 May 31, 2020 Raw materials $ 1,583,000 $ 1,635,000 Work in progress 1,006,000 988,000 Finished products 617,000 228,000 Total $ 3,206,000 $ 2,851,000
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	2021 2020 Dividend yield 0% 0% Expected volatility 71.19-107.53% 55.52-72.62% Risk free interest rate 0.34-1.18% 0.43-1.80% Expected Term 5.50-6.25 Years 3.75-6.25 Years
Disaggregation of Revenue [Table Text Block]	Year Ended May 31, 2021 May 31, 2020 Clinical lab $ 3,077,000 $ 2,922,000 Physician's office 2,801,000 2,195,000 Over-the-counter 766,000 1,270,000 Contract manufacturing 552,000 306,000 Lab supplies 3,000 - Total $ 7,199,000 $ 6,693,000

PROPERTY AND EQUIPMENT, NET (Ta

PROPERTY AND EQUIPMENT, NET (Tables)	12 Months Ended
	May 31, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment [Table Text Block]	2021 2020 Equipment $ 1,849,888 $ 1,921,833 Furniture, fixtures and leasehold improvements 432,989 225,189 Less accumulated depreciation (1,972,357) (1,867,643) Net property and equipment $ 310,520 $ 279,379

INTANGIBLE ASSETS, NET (Tables)

INTANGIBLE ASSETS, NET (Tables)	12 Months Ended
	May 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets [Table Text Block]	2021 2020 Licenses $ 182,176 $ 551,397 Patents 239,423 113,382 Less accumulated amortization-licenses (107,194) (487,989) Less accumulated amortization-patents (19,575) (8,135) Intangible asssets, net $ 294,830 $ 168,655
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	2022 $ 21,846 2023 20,058 2024 20,058 2025 19,071 2026 18,975 Thereafter 194,822 Total $ 294,830

ACCOUNTS PAYABLE AND ACCRUED _2

ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Tables)	12 Months Ended
	May 31, 2021
Payables and Accruals [Abstract]
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	2021 2020 Accounts payable $ 431,621 $ 833,412 Accrued expense 151,759 153,299 Total $ 583,380 $ 986,711

SHAREHOLDERS' EQUITY (Tables)

SHAREHOLDERS' EQUITY (Tables)	12 Months Ended
	May 31, 2021
Stockholders' Equity Note [Abstract]
Share-based Payment Arrangement, Option, Activity [Table Text Block]	NUMBER OF STOCK OPTIONS EXCERCISE PRICE WEIGHTED AVERAGE EXERCISE Options outstanding at May 31, 2019 1,476,209 $0.82-$3.90 $ 2.07 Options granted 517,500 $2.68-$8.18 $ 4.47 Options excercised (137,958) $0.82-$3.90 $ 1.64 Options canceled or expired (66,500) $0.85-$8.18 $ 3.43 Options outstanding at May 31, 2020 1,789,251 $0.82-$8.18 $ 2.75 Options granted 430,616 $5.14-$8.70 $ 6.73 Options excercised (86,750) $0.82-$3.62 $ 1.20 Options canceled or expired (51,751) $2.35-$8.18 $ 4.77 Options outstanding at May 31, 2021 2,081,366 $0.82-$8.70 $ 3.59
Schedule of Nonvested Share Activity [Table Text Block]	Number of Stock options Non-vested shares at May 31, 2020 822,584 $ 3.78 Granted 430,616 6.73 Vested (409,459) 3.36 Forfeited (50,500) 4.80 Non-vested shares at May 31, 2021 793,241 $ 5.54
Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]	RANGE OF NUMBER WEIGHTED WEIGHTED NUMBER WEIGHTED $0.82-$1.04 216,000 3.75 $0.82 216,000 $0.82 $1.20-$2.81 1,024,500 6.45 $2.17 795,250 $2.02 $3.62-$8.70 840,866 8.00 $6.03 276,875 $4.54

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	May 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	Years ended May 31, 2021 2020 Current: U.S. Federal $ - $ - Foreign Taxes Subsidiaries (12,257) (6,590) State and local (800) (800) Total current (13,057) (7,390) Deferred: U.S. Federal - - State and local - - Total deferred - - Income tax expense $ (13,057) $ (7,390)
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	Years ended May 31, 2021 2020 Computed "expected" tax benefit $ 1,560,971 $ 560,656 Increase (reduction) in income taxes resulting from: Change in valuation allowance (2,292,366) (1,152,000) State income taxes, net of federal benefit 217,559 83,202 Research and development tax credits 456,388 131,461 Permanent tax differences and other (88,051) 179,042 Stock based compensation benefit 144,699 196,839 Foreign taxes of subsidiaries (12,257) (6,590) Income tax expense $ (13,057) $ (7,390)
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	As of May 31, 2021 2020 Deferred tax assets: Accounts receivable, principally due to allowance for doubtful accounts $ 200,000 $ 17,000 Inventory valuation 387,000 16,000 Compensated absences 85,000 64,000 Net operating loss carryforwards 3,194,000 2,286,000 Tax credit carryforwards 1,055,000 599,000 Deferred rent expense/Capitalized leases 15,000 17,000 Stock Options 613,000 304,000 Losses of foreign subsidiaries & Other, net 370,000 304,000 Accumulated depreciation and amortization (15,000) 5,000 Total deferred tax assets 5,904,000 3,612,000 Less valuation allowance (5,904,000) (3,612,000) Net deferred tax asset $ - $ -

GEOGRAPHIC INFORMATION (Tables)

GEOGRAPHIC INFORMATION (Tables)	12 Months Ended
	May 31, 2021
Geographic Information Disclosure [Abstract]
Revenue from External Customers by Geographic Areas [Table Text Block]	Year Ended May 31, 2021 May 31, 2020 Revenues from sales to unaffiliated customers: Europe $ 4,301,000 60% $ 2,434,000 36% Asia 1,908,000 26% 1,867,000 28% United States 548,000 8% 445,000 7% South America 250,000 3% 1,615,000 24% Middle East 192,000 3% 314,000 5% Other - 0% 18,000 0% Total $ 7,199,000 100% $ 6,693,000 100%

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	May 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule Of Cash Flow Supplemental Disclosures Related To Lease [Table Text Block]	2021 2020 Operating cash flows from operating leases $ 320,606 $ 311,742 Right-of-use assets obtained in exchange for $ 79,159 $ - Weighted average remaining lease term (in years) 5.27 6.27 Weighted average discount rate 6.50% 6.50%
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	2022 $ 337,630 2023 350,311 2024 360,769 2025 371,539 2026 382,631 Thereafter 103,927 Total undiscounted lease payments 1,906,807 Less imputed interest 287,293 Total operating lease liabilities $ 1,619,514

RESTATEMENT OF PREVIOUSLY ISS_2

RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Tables)	12 Months Ended
	May 31, 2021
Prior Period Adjustment [Abstract]
Schedule of Error Corrections and Prior Period Adjustments [Table Text Block]	As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 36,685,176 $ 2,151,567 $ 38,836,743 Accumulated deficit (28,394,768) (2,151,567) (30,546,335) Other Equity accounts 936,615 - 936,615 Total Shareholders' Equity $ 9,227,023 $ - $ 9,227,023 As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,213,707 $ 1,174,349 $ 36,388,056 Accumulated deficit (21,925,732) (1,174,349) (23,100,081) Other Equity accounts 925,078 - 925,078 Total Shareholders' Equity $ 14,213,053 $ - $ 14,213,053 As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 22,830,006 $ 836,232 $ 23,666,238 Accumulated deficit (19,586,678) (836,232) (20,422,910) Other Equity accounts 737,642 - 737,642 Total Shareholders' Equity $ 3,980,970 $ - $ 3,980,970 As Previously Reported Adjustments As Restated Cost of sales $ 6,702,046 $ 130,696 $ 6,832,742 Gross Profit 496,981 (130,696) 366,285 Operating Expenses: Selling, general and administrative 4,608,950 785,575 5,394,525 Research and development 2,410,506 60,947 2,471,453 Total operating expense 7,019,456 846,522 7,865,978 Loss from operations (6,522,475) (977,218) (7,499,693) Loss before income taxes (6,455,979) (977,218) (7,433,197) Net loss $ (6,469,036) $ (977,218) $ (7,446,254) Basic net loss per common share $ (0.54) $ (0.08) $ (0.62) Diluted net loss per common share $ (0.54) $ (0.08) $ (0.62) Comprehensive loss $ (6,477,151) $ (977,218) $ (7,454,369) As Previously Reported Adjustments As Restated Cost of sales $ 4,910,935 $ 43,549 $ 4,954,484 Gross Profit 1,781,776 (43,549) 1,738,227 Operating Expenses: Selling, general and administrative 2,274,415 272,207 2,546,622 Research and development 1,910,209 22,361 1,932,570 Total operating expense 4,184,624 294,568 4,479,192 Loss from operations (2,402,848) (338,117) (2,740,965) Loss before income taxes (2,331,664) (338,117) (2,669,781) Net loss $ (2,339,054) $ (338,117) $ (2,677,171) Basic net loss per common share $ (0.23) $ (0.03) $ (0.26) Diluted net loss per common share $ (0.23) $ (0.03) $ (0.26) Comprehensive loss $ (2,342,364) $ (338,117) $ (2,680,481) As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (6,469,036) $ (977,218) $ (7,446,254) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 377,391 977,218 1,354,609 Net cash used in operating activities (5,251,748) - (5,251,748) Cash and cash equivalents at end of year $ 4,199,311 $ - $ 4,199,311 As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (2,339,054) $ (338,117) $ (2,677,171) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 200,470 338,117 538,587 Net cash used in operating activities (4,297,498) - (4,297,498) Cash and cash equivalents at end of year $ 8,641,027 $ - $ 8,641,027 As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,231,415 $ 1,417,328 $ 36,648,743 Accumulated deficit (23,575,147) (1,417,328) (24,992,475) Other Equity accounts 924,357 - 924,357 Total Shareholders' Equity $ 12,580,625 $ - $ 12,580,625 As Previously Reported Adjustments As Restated Cost of sales $ 960,930 $ 64,787 $ 1,025,717 Gross Profit 182,876 (64,787) 118,089 Operating Expenses: Selling, general and administrative 1,164,564 141,380 1,305,944 Research and development 674,693 36,812 711,505 Total operating expense 1,839,257 178,192 2,017,449 Loss from operations (1,656,381) (242,979) (1,899,360) Loss before income taxes (1,648,290) (242,979) (1,891,269) Net loss $ (1,649,415) $ (242,979) $ (1,892,394) Basic net loss per common share $ (0.14) $ (0.02) $ (0.16) Diluted net loss per common share $ (0.14) $ (0.02) $ (0.16) Comprehensive loss $ (1,651,136) $ (242,979) $ (1,894,115) As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (1,649,415) $ (242,979) $ (1,892,394) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 3,808 242,979 246,787 Net cash used in operating activities (1,597,146) - (1,597,146) Cash and cash equivalents at end of period $ 6,964,314 $ - $ 6,964,314 As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 35,284,864 $ 1,650,262 $ 36,935,126 Accumulated deficit (25,060,311) (1,650,262) (26,710,573) Other Equity accounts 924,228 - 924,228 Total Shareholders' Equity $ 11,148,781 $ - $ 11,148,781 As Previously Reported Adjustments As Restated Cost of sales $ 1,971,960 $ 117,564 $ 2,089,524 Gross Profit 544,372 (117,564) 426,808 Operating Expenses: Selling, general and administrative 2,419,411 291,379 2,710,790 Research and development 1,261,096 66,970 1,328,066 Total operating expense 3,680,507 358,349 4,038,856 Loss from operations (3,136,135) (475,913) (3,612,048) Loss before income taxes (3,120,061) (475,913) (3,595,974) Net loss $ (3,134,579) $ (475,913) $ (3,610,492) Basic net loss per common share $ (0.27) $ (0.04) $ (0.31) Diluted net loss per common share $ (0.27) $ (0.04) $ (0.31) Comprehensive loss $ (3,137,829) $ (475,913) $ (3,613,742) As Previously Reported Adjustments As Restated Cost of sales $ 1,011,030 $ 52,777 $ 1,063,807 Gross Profit 361,496 (52,777) 308,719 Operating Expenses: Selling, general and administrative 1,254,847 149,999 1,404,846 Research and development 586,403 30,158 616,561 Total operating expense 1,841,250 180,157 2,021,407 Loss from operations (1,479,754) (232,934) (1,712,688) Loss before income taxes (1,471,771) (232,934) (1,704,705) Net loss $ (1,485,164) $ (232,934) $ (1,718,098) Basic net loss per common share $ (0.13) $ (0.02) $ (0.15) Diluted net loss per common share $ (0.13) $ (0.02) $ (0.15) Comprehensive loss $ (1,486,694) $ (232,934) $ (1,719,628) As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (3,134,579) $ (475,913) $ (3,610,492) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 24,227 475,913 500,140 Net cash used in operating activities (2,880,218) - (2,880,218) Cash and cash equivalents at end of period $ 5,683,787 $ - $ 5,683,787 As Previously Reported Adjustments As Restated Shareholders' Equity: Additional paid-in-capital $ 36,563,562 $ 1,935,493 $ 38,499,055 Accumulated deficit (26,899,621) (1,935,493) (28,835,114) Other Equity accounts 935,642 - 935,642 Total Shareholders' Equity $ 10,599,583 $ - $ 10,599,583 As Previously Reported Adjustments As Restated Cost of sales $ 5,639,103 $ 152,490 $ 5,791,593 Gross Profit 505,867 (152,490) 353,377 Operating Expenses: Selling, general and administrative 3,697,804 540,933 4,238,737 Research and development 1,824,312 67,721 1,892,033 Total operating expense 5,522,116 608,654 6,130,770 Loss from operations (5,016,249) (761,144) (5,777,393) Loss before income taxes (4,962,488) (761,144) (5,723,632) Net loss $ (4,973,889) $ (761,144) $ (5,735,033) Basic net loss per common share $ (0.42) $ (0.07) $ (0.49) Diluted net loss per common share $ (0.42) $ (0.07) $ (0.49) Comprehensive loss $ (4,982,576) $ (761,144) $ (5,743,720) As Previously Reported Adjustments As Restated Cost of sales $ 3,667,143 $ 34,926 $ 3,702,069 Gross Loss (38,505) (34,926) (73,431) Operating Expenses: Selling, general and administrative 1,278,393 249,554 1,527,947 Research and development 563,216 751 563,967 Total operating expense 1,841,609 250,305 2,091,914 Loss from operations (1,880,114) (285,231) (2,165,345) Loss before income taxes (1,842,427) (285,231) (2,127,658) Net loss $ (1,839,310) $ (285,231) $ (2,124,541) Basic net loss per common share $ (0.15) $ (0.03) $ (0.18) Diluted net loss per common share $ (0.15) $ (0.03) $ (0.18) Comprehensive loss $ (1,844,747) $ (285,231) $ (2,129,978) As Previously Reported Adjustments As Restated Cash flows from operating activities: Net loss $ (4,973,889) $ (761,144) $ (5,735,033) Adjustments to reconcile net loss to net cash used in operating activities: Stock option expense 261,176 761,144 1,022,320 Net cash used in operating activities (4,244,064) - (4,244,064) Cash and cash equivalents at end of period $ 5,272,565 $ - $ 5,272,565

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020	Jan. 22, 2021
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Retained Earnings (Accumulated Deficit)	$ (30,546,335)	$ (23,100,081)
Shelf Registration Statement, Maximum Authorized Common Stock Issuance, Value			$ 15,000,000
Proceeds from Issuance of Common Stock	1,011,475	10,232,857
Proceeds from Stock Options Exercised	102,255	223,534
Cash, Uninsured Amount	$ 3,767,000
Concentration Risk, Percentage	100.00%
Other Receivables, Gross, Current	$ 2,292,466	1,836,852
Property, Plant and Equipment, Net	$ 310,520	279,379
Threshold Period Past Due for Write-off of Trade Accounts Receivable	90 days
Accounts Receivable, Credit Loss Expense (Reversal)	$ 766,434	(2,129)
Increase (Decrease) in Prepaid Supplies	370,000	1,000,000
Inventory Valuation Reserves	1,617,000	67,000
Inventory, LIFO Reserve	1,502,675
Depreciation, Depletion and Amortization	104,715	105,299
Amortization of Intangible Assets	$ 33,552	23,873
Equity Method Investment, Ownership Percentage	6.00%
Research and Development Expense	$ 2,471,453	1,932,570
Deferred Tax Assets, Valuation Allowance	5,904,000	3,612,000
Deferred Tax Assets, Gross	5,904,000	3,612,000
Advertising Expense	10,070	174
Operating Lease, Right-of-Use Asset	1,553,081	$ 1,711,510
Operating Lease, Liability	$ 1,619,514
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)	2,081,366	1,789,251
ATM Agreement [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Proceeds from Issuance of Common Stock	$ 1,177,394
Proceeds from Stock Options Exercised	$ 1,011,475
Series A Preferred Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Convertible Preferred Stock, Shares Issued upon Conversion (in Shares)	321,429
Common Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Sale of Stock, Number of Shares Issued in Transaction (in Shares)	158,889
Proceeds from Issuance of Common Stock	$ 1,011,475
Proceeds from Stock Options Exercised		$ 223,534
Accounts Receivable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Accounts Receivable, Credit Loss Expense (Reversal)	$ 837,415
Distribution Rights [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years
Purchased Technology Rights [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Patents [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Minimum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Minimum [Member] | Common Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Share Price (in Dollars per share)	$ 7.06
Maximum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] | Common Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Share Price (in Dollars per share)	$ 7.79
Retained Earnings [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Retained Earnings (Accumulated Deficit)	$ 30,500,000
5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Preferred Stock, Shares Outstanding (in Shares)	0	321,429
MEXICO
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Inventory, Gross	$ 803,000	$ 613,000
Property, Plant and Equipment, Net	$ 25,000	$ 31,000
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Two Distributors [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	60.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Three Distributors [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage		57.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | One Distributors [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	33.00%	26.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Two Distributors [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	73.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Three Distributors [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage		80.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Distributors in China [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	41.00%
Supplier Concentration Risk [Member] | Cost of Goods and Service, Product and Service Benchmark [Member] | One Vendor [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	58.00%	59.00%
Accounting Standards Update 2016-02 [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Operating Lease, Right-of-Use Asset	$ 1,942,999
Operating Lease, Liability	$ 1,980,970

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Inventories - USD ($)	May 31, 2021	May 31, 2020
Inventories [Abstract]
Raw materials	$ 1,583,000	$ 1,635,000
Work in progress	1,006,000	988,000
Finished products	617,000	228,000
Total	$ 3,206,255	$ 2,850,836

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Share based compensation assumptions	12 Months Ended
	May 31, 2021	May 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Share based compensation assumptions [Line Items]
Dividend yield	0.00%	0.00%
Minimum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Share based compensation assumptions [Line Items]
Expected volatility	71.19%	55.52%
Risk free interest rate	0.34%	0.43%
Expected Term	5 years 6 months	3 years 9 months
Maximum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Share based compensation assumptions [Line Items]
Expected volatility	107.53%	72.62%
Risk free interest rate	1.18%	1.80%
Expected Term	6 years 3 months	6 years 3 months

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Revenue from contracts with customers - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Disaggregation of Revenue [Line Items]
Revenue From Customers	$ 7,199,000	$ 6,693,000
Clinical Lab [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	3,077,000	2,922,000
Physicians Office [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	2,801,000	2,195,000
Over-the-counter [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	766,000	1,270,000
Contract Manufacturing [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	552,000	$ 306,000
Lab Supplies [Member]
Disaggregation of Revenue [Line Items]
Revenue From Customers	$ 3,000

PROPERTY AND EQUIPMENT, NET (De

PROPERTY AND EQUIPMENT, NET (Details) - Property and equipment, net - USD ($)	May 31, 2021	May 31, 2020
Property and equipment, net [Abstract]
Equipment	$ 1,849,888	$ 1,921,833
Furniture, fixtures and leasehold improvements	432,989	225,189
Less accumulated depreciation	(1,972,357)	(1,867,643)
Net property and equipment	$ 310,520	$ 279,379

INTANGIBLE ASSETS, NET (Details

INTANGIBLE ASSETS, NET (Details) - Intangible assets, net - USD ($)	May 31, 2021	May 31, 2020
Intangible assets, net [Abstract]
Licenses	$ 182,176	$ 551,397
Patents	239,423	113,382
Less accumulated amortization-licenses	(107,194)	(487,989)
Less accumulated amortization-patents	(19,575)	(8,135)
Intangible asssets, net	$ 294,830	$ 168,655

INTANGIBLE ASSETS, NET (Detai_2

INTANGIBLE ASSETS, NET (Details) - Expected amortization of intangible assets	May 31, 2021USD ($)
Expected amortization of intangible assets [Abstract]
2022	$ 21,846
2023	20,058
2024	20,058
2025	19,071
2026	18,975
Thereafter	194,822
Total	$ 294,830

ACCOUNTS PAYABLE AND ACCRUED _3

ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Details) - Customer Concentration Risk [Member] - Accounts Payable [Member]	12 Months Ended
	May 31, 2021	May 31, 2020
One Vendor [Member]
ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Details) [Line Items]
Concentration Risk, Percentage	17.00%
Two Vendors [Member]
ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Details) [Line Items]
Concentration Risk, Percentage		27.00%

ACCOUNTS PAYABLE AND ACCRUED _4

ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Details) - Accounts payable and accrued expense balances - USD ($)	May 31, 2021	May 31, 2020
Accounts payable and accrued expense balances [Abstract]
Accounts payable	$ 431,621	$ 833,412
Accrued expense	151,759	153,299
Total	$ 583,380	$ 986,711

SHAREHOLDERS' EQUITY (Details)

SHAREHOLDERS' EQUITY (Details) - USD ($)	May 31, 2021	Jan. 22, 2021	Jan. 21, 2021	Dec. 10, 2020	Jul. 21, 2020	Mar. 20, 2020	Feb. 24, 2020	Dec. 31, 2017	Dec. 01, 2017	Dec. 31, 2014	Aug. 31, 2010	May 31, 2021	May 31, 2020	Mar. 19, 2020	May 21, 2021	Feb. 29, 2020	Feb. 11, 2020
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares (in Shares)												409,459
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)												$ 6.73
Proceeds from Stock Options Exercised												$ 102,255	$ 223,534
Proceeds from Issuance of Common Stock												1,011,475	10,232,857
Stock Issued During Period, Value, Stock Options Exercised												102,255	223,534
Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares (in Shares)				64,584
Share-based Payment Arrangement, Expense	$ 184,000											$ 1,354,609	$ 538,587
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)												$ 6.73	$ 4.47
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value												$ 501,000	$ 589,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	2,132,000											2,132,000	6,923,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	1,872,000											1,872,000	4,442,000
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 2,156,000											$ 2,156,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition												2 years 215 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term												6 years 25 days
General and Administrative Expense [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Payment Arrangement, Expense												$ 956,898	416,953
Cost of Sales [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Payment Arrangement, Expense												204,509	66,444
Research and Development Expense [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Payment Arrangement, Expense												125,439	40,254
Selling and Marketing Expense [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Payment Arrangement, Expense												$ 67,763	$ 14,936
5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Preferred Stock, Shares Authorized (in Shares)	571,429						571,429					571,429	571,429				571,429
Conversion of Stock, Shares Converted (in Shares)							250,000
Preferred Stock, Par or Stated Value Per Share (in Dollars per share)	$ 0.08											$ 0.08	$ 0.08
Preferred Stock, Dividends Per Share, Declared (in Dollars per share)												$ 0.175
Common Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares)													137,958
Proceeds from Stock Options Exercised													$ 223,534
Sale of Stock, Consideration Received on Transaction												$ 1,177,394
Proceeds from Issuance of Common Stock												$ 1,011,475
Sale of Stock, Number of Shares Issued in Transaction (in Shares)												158,889
Common Stock [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)															900,000
Proceeds from Stock Options Exercised												$ 102,255
Stock Issued During Period, Value, Stock Options Exercised												$ 86,750
Common Stock [Member] | At Market Issuance Sales Agreement [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Sale of Stock, Consideration Received on Transaction													10,232,857	$ 6,997,935
Proceeds from Issuance of Common Stock													$ 3,771,048
Sale of Stock, Number of Shares Issued in Transaction (in Shares)													1,674,943
Minimum [Member] | Common Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share)													$ 0.82
Sale of Stock, Price Per Share (in Dollars per share)	7.06											$ 7.06
Minimum [Member] | Common Stock [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share)												0.82
Minimum [Member] | Common Stock [Member] | At Market Issuance Sales Agreement [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Sale of Stock, Price Per Share (in Dollars per share)													2.33
Maximum [Member] | Common Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share)													3.90
Sale of Stock, Price Per Share (in Dollars per share)	$ 7.79											7.79
Maximum [Member] | Common Stock [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in Dollars per share)												$ 3.62
Maximum [Member] | Common Stock [Member] | At Market Issuance Sales Agreement [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Sale of Stock, Consideration Received on Transaction									$ 7,000,000
Sale of Stock, Price Per Share (in Dollars per share)									$ 0.08				$ 9.08
Common Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares)												86,750	137,958
Conversion of Stock, Shares Converted (in Shares)												321,429	250,000
Stock Issued During Period, Value, Stock Options Exercised												$ 6,940	$ 11,037
Common Stock [Member] | 5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Conversion of Stock, Shares Converted (in Shares)			321,429				571,429					321,429	250,000
Preferred Stock, Par or Stated Value Per Share (in Dollars per share)							$ 0.08
Conversion of Stock, Amount Issued							$ 2,000,000
Shares Issued, Price Per Share (in Dollars per share)							$ 3.50
Conversion of Stock, Shares Issued (in Shares)							250,000
Stock Issued During Period, Shares, Conversion of Units (in Shares)					571,429
2010 Plan [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)											850,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent											80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period											10 years
2014 Plan [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)										850,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent										80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period										10 years
2017 Plan [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)								900,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent								80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period								10 years
2020 Plan [Member] | Share-based Payment Arrangement, Option [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)																900,000
Registration Rights Agreement [Member] | Common Stock [Member] | At Market Issuance Sales Agreement [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Sale of Stock, Consideration Received on Transaction						$ 12,500,000
Proceeds from Issuance of Common Stock													$ 6,817,330
Registration Rights Agreement [Member] | Maximum [Member] | Common Stock [Member] | At Market Issuance Sales Agreement [Member]
SHAREHOLDERS' EQUITY (Details) [Line Items]
Sale of Stock, Consideration Received on Transaction		$ 15,000,000

SHAREHOLDERS' EQUITY (Details)

SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity - $ / shares	12 Months Ended
	May 31, 2021	May 31, 2020
Exercise Price Range Per Share $0.82 - $3.90 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options outstanding, number of stock options		1,476,209
Options outstanding, weighted average exercise price		$ 2.07
Options exercised, number of stock options		(137,958)
Options exercised, weighted average exercise price		$ 1.64
Exercise Price Range Per Share $2.68 - $8.18 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options granted, number of stock options		517,500
Options granted, weighted average exercise price		$ 4.47
Exercise Price Range Per Share $0.85 - $8.18 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options canceled or expired, number of stock options		(66,500)
Options canceled or expired, weighted average exercise price		$ 3.43
Exercise Price Range Per Share $0.82 - $8.18 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options outstanding, number of stock options	1,789,251
Options outstanding, weighted average exercise price	$ 2.75
Options outstanding, number of stock options		1,789,251
Options outstanding, weighted average exercise price		$ 2.75
Exercise Price Range Per Share $5.14 - $8.70 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options granted, number of stock options	430,616
Options granted, weighted average exercise price	$ 6.73
Exercise Price Range Per Share $0.82 - $3.62 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options exercised, number of stock options	(86,750)
Options exercised, weighted average exercise price	$ 1.20
Exercise Price Range Per Share $2.35 - $8.18 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options canceled or expired, number of stock options	(51,751)
Options canceled or expired, weighted average exercise price	$ 4.77
Exercise Price Range Per Share $0.82 - $8.70 [Member]
SHAREHOLDERS' EQUITY (Details) - Outstanding Stock Options Activity [Line Items]
Options outstanding, number of stock options
Options outstanding, weighted average exercise price
Options outstanding, number of stock options	2,081,366
Options outstanding, weighted average exercise price	$ 3.59

SHAREHOLDERS' EQUITY (Details_2

SHAREHOLDERS' EQUITY (Details) - Non-vested Stock Options Activity	12 Months Ended
	May 31, 2021$ / sharesshares
Non-vested Stock Options Activity [Abstract]
Non-vested shares, number of shares | shares	822,584
Non-vested shares, weighted average grant date fair value | $ / shares	$ 3.78
Granted, number of shares | shares	430,616
Granted, weighted average grant date fair value | $ / shares	$ 6.73
Vested, number of shares | shares	(409,459)
Vested, weighted average grant date fair value | $ / shares	$ 3.36
Forfeited, number of shares | shares	(50,500)
Forfeited, weighted average grant date fair value | $ / shares	$ 4.80
Non-vested shares, number of shares | shares	793,241
Non-vested shares, weighted average grant date fair value | $ / shares	$ 5.54

SHAREHOLDERS' EQUITY (Details_3

SHAREHOLDERS' EQUITY (Details) - Stock Options Summary	12 Months Ended
	May 31, 2021$ / sharesshares
Range Of Exercise Price $0.82 - $1.04 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	$ 0.82
Range of Exercise Price, Maximum	$ 1.04
Options Outstanding, Number (in Shares) | shares	216,000
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 9 months
Options Outstanding, Weighted Average Exercise Price	$ 0.82
Options Exercisable, Number (in Shares) | shares	216,000
Options Exercisable, Weighted Average Exercise Price	$ 0.82
Range Of Exercise Price $1.20 - $2.81 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	1.20
Range of Exercise Price, Maximum	$ 2.81
Options Outstanding, Number (in Shares) | shares	1,024,500
Options Outstanding, Weighted Average Remaining Contractual Life	6 years 164 days
Options Outstanding, Weighted Average Exercise Price	$ 2.17
Options Exercisable, Number (in Shares) | shares	795,250
Options Exercisable, Weighted Average Exercise Price	$ 2.02
Range Of Exercise Price $3.62 - $8.70 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	3.62
Range of Exercise Price, Maximum	$ 8.70
Options Outstanding, Number (in Shares) | shares	840,866
Options Outstanding, Weighted Average Remaining Contractual Life	8 years
Options Outstanding, Weighted Average Exercise Price	$ 6.03
Options Exercisable, Number (in Shares) | shares	276,875
Options Exercisable, Weighted Average Exercise Price	$ 4.54

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
INCOME TAXES (Details) [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Deferred Tax Assets, Valuation Allowance	$ 5,904,000	$ 3,612,000
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	2,292,000	1,152,000
Equity Option [Member]
INCOME TAXES (Details) [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		$ 437,000
Domestic Tax Authority [Member]
INCOME TAXES (Details) [Line Items]
Operating Loss Carryforwards	12,957,000
California State Income Tax [Member]
INCOME TAXES (Details) [Line Items]
Operating Loss Carryforwards	6,768,000
Research Tax Credit Carryforward [Member] | Domestic Tax Authority [Member]
INCOME TAXES (Details) [Line Items]
Tax Credit Carryforward, Amount	715,000
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member]
INCOME TAXES (Details) [Line Items]
Tax Credit Carryforward, Amount	$ 341,000

INCOME TAXES (Details) - Income

INCOME TAXES (Details) - Income tax expense - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Current:
U.S. Federal
Foreign Taxes Subsidiaries	(12,257)	(6,590)
State and local	(800)	(800)
Total current	(13,057)	(7,390)
Deferred:
U.S. Federal
State and local
Total deferred
Income tax expense	$ (13,057)	$ (7,390)

INCOME TAXES (Details) - Inco_2

INCOME TAXES (Details) - Income Tax Rate Reconciliation - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Income Tax Rate Reconciliation [Abstract]
Computed "expected" tax benefit	$ 1,560,971	$ 560,656
Change in valuation allowance	(2,292,366)	(1,152,000)
State income taxes, net of federal benefit	217,559	83,202
Research and development tax credits	456,388	131,461
Permanent tax differences and other	(88,051)	179,042
Stock based compensation benefit	144,699	196,839
Foreign taxes of subsidiaries	(12,257)	(6,590)
Income tax expense	$ (13,057)	$ (7,390)

INCOME TAXES (Details) - Deferr

INCOME TAXES (Details) - Deferred Tax - USD ($)	May 31, 2021	May 31, 2020
Deferred tax assets:
Accounts receivable, principally due to allowance for doubtful accounts	$ 200,000	$ 17,000
Inventory valuation	387,000	16,000
Compensated absences	85,000	64,000
Net operating loss carryforwards	3,194,000	2,286,000
Tax credit carryforwards	1,055,000	599,000
Deferred rent expense/Capitalized leases	15,000	17,000
Stock Options	613,000	304,000
Losses of foreign subsidiaries & Other, net	370,000	304,000
Accumulated depreciation and amortization	(15,000)	5,000
Total deferred tax assets	5,904,000	3,612,000
Less valuation allowance	(5,904,000)	(3,612,000)
Net deferred tax asset

GEOGRAPHIC INFORMATION (Details

GEOGRAPHIC INFORMATION (Details)	12 Months Ended
	May 31, 2021
Geographic Information Disclosure [Abstract]
Number of Operating Segments	1

GEOGRAPHIC INFORMATION (Detai_2

GEOGRAPHIC INFORMATION (Details) - Geographic information regarding net sales - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Revenues from sales to unaffiliated customers:
Net Sales	$ 7,199,027	$ 6,692,711
Net Sales Percent	100.00%
Europe [Member]
Revenues from sales to unaffiliated customers:
Net Sales	$ 4,301,000	2,434,000
Asia [Member]
Revenues from sales to unaffiliated customers:
Net Sales	1,908,000	1,867,000
UNITED STATES
Revenues from sales to unaffiliated customers:
Net Sales	548,000	445,000
South America [Member]
Revenues from sales to unaffiliated customers:
Net Sales	250,000	1,615,000
Middle East [Member]
Revenues from sales to unaffiliated customers:
Net Sales	192,000	314,000
Other [Member]
Revenues from sales to unaffiliated customers:
Net Sales		$ 18,000
Geographic Concentration Risk [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	100.00%	100.00%
Geographic Concentration Risk [Member] | Europe [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	60.00%	36.00%
Geographic Concentration Risk [Member] | Asia [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	26.00%	28.00%
Geographic Concentration Risk [Member] | UNITED STATES | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	8.00%	7.00%
Geographic Concentration Risk [Member] | South America [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	3.00%	24.00%
Geographic Concentration Risk [Member] | Middle East [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	3.00%	5.00%
Geographic Concentration Risk [Member] | Other [Member] | Revenue, Segment Benchmark [Member]
Revenues from sales to unaffiliated customers:
Net Sales Percent	0.00%	0.00%

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details) - USD ($)

Sep. 01, 2021

May 07, 2020

Sep. 30, 2017

Nov. 30, 2016

May 25, 2016

Nov. 30, 2015

Aug. 26, 2021

May 31, 2021

May 31, 2020

Jun. 25, 2020

May 28, 2020

Dec. 31, 2019

Sep. 25, 2019

Jul. 22, 2019

Jul. 12, 2019

Jan. 31, 2018

Nov. 30, 2017

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Research and Development Expense

$ 2,471,453

$ 1,932,570

Accrued Liabilities, Current

151,759

153,299

University OF Southern California [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 82,472

Research and Development Expense

12,567

2,200

Other Expenses

$ 14,767

Accrued Liabilities, Current

17,064

University OF Michigan [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 181,015

Research and Development Expense

20,550

30,900

Accrued Liabilities, Current

$ 2,050

Billed Commitment, Percentage

56.00%

University OF Beth Israel Deaconess Medical Center [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 305,000

$ 142,000

Research and Development Expense

0

141,640

Biomerica HP Stool Antigen [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 117,200

Research and Development Expense

13,111

13,355

Biomerica InFoods [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 107,000

Research and Development Expense

12,675

20,875

Accrued Liabilities, Current

$ 19,600

Billed Commitment, Percentage

31.00%

Medical Practice [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 136,000

Research and Development Expense

$ 11,725

45,250

Accrued Liabilities, Current

5,975

Billed Commitment, Percentage

42.00%

Biomerica H. Pylori Product [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 57,800

Research and Development Expense

$ 41,845

Billed Commitment, Percentage

72.00%

Houseton Methodist Research Institute [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 133,000

Research and Development Expense

$ 0

$ 4,000

Accrued Liabilities, Current

3,550

Billed Commitment, Percentage

3.00%

Mayo Clinic Arizona [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 135,515

Research and Development Expense

0

17,390

Accrued Liabilities, Current

$ 3,750

Billed Commitment, Percentage

13.00%

Mayo Clinic Jacksonville [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 135,515

Accrued Liabilities, Current

17,390

Billed Commitment, Percentage

17.00%

Related Party Transaction, Amounts of Transaction

$ 22,827

University Of Texas Health Science Center [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Clinical Trial Agreement Maximum Budgeted Costs

$ 139,850

Research and Development Expense

4,850

Accrued Liabilities, Current

$ 3,750

Billed Commitment, Percentage

4.00%

Royalty Agreements [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Royalty Expense

$ 11,000

15,000

Telcon Agreement [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Accrued Fees and Other Revenue Receivable

$ 1,250,000

Stock Issued During Period, Shares, Other (in Shares)

83,333

Proceeds from Fees Received

$ 250,000

Royalty Percentage

15.00%

Mount Sinai License Agreements [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Related Party Transaction, Purchases from Related Party

$ 5,100

Mount Sinai License Agreements [Member] | Subsequent Event [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Related Party Transaction, Purchases from Related Party

$ 2,850

UC License Agreements [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Payments for Other Fees

$ 5,000

License Maintenance Fee, Payable

$ 10,000

UC License Agreements [Member] | Subsequent Event [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Payments for Other Fees

$ 5,000

Building In Irvine California [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Operating Lease, Expense

$ 23,637

Building In Irvine California [Member] | Subsequent Event [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Rental Expense, Increase During Period

$ 25,970

Rental Expense, Increase During The Period, Percentage

3.00%

Lease Deposit Liability

$ 22,080

Building In Irvine California [Member] | First Amendment To Lease [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Operating Leases Rent Expenses Minimum Rentals

$ 21,000

Rental Expense, Increase During Period

$ 23,637

Lease Expiration Date

Aug. 31, 2021

Revenue Benchmark [Member] | Royalty Agreements [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Royalty Expense Percentage Of Sales

1.50%

1.80%

MEXICO

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Operating Lease, Expense

$ 25,351

$ 43,481

MEXICO | Property Available for Operating Lease [Member]

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Operating Leases Rent Expenses Minimum Rentals

$ 2,926

Operating Lease, Expense

$ 3,262

Lease Expiration Period

10 years

UNITED STATES

COMMITMENTS AND CONTINGENCIES (Details) [Line Items]

Operating Lease, Expense

$ 294,759

$ 300,267

COMMITMENTS AND CONTINGENCIES_3

COMMITMENTS AND CONTINGENCIES (Details) - Supplemental cash flow information related to leases - USD ($)	12 Months Ended
	May 31, 2021	May 31, 2020
Supplemental cash flow information related to leases [Abstract]
Operating cash flows from operating leases	$ 320,606	$ 311,742
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 79,159
Weighted average remaining lease term (in years)	5 years 98 days	6 years 98 days
Weighted average discount rate	6.50%	6.50%

COMMITMENTS AND CONTINGENCIES_4

COMMITMENTS AND CONTINGENCIES (Details) - The maturity of lease liabilities	May 31, 2021USD ($)
The maturity of lease liabilities [Abstract]
2022	$ 337,630
2023	350,311
2024	360,769
2025	371,539
2026	382,631
Thereafter	103,927
Total undiscounted lease payments	1,906,807
Less imputed interest	287,293
Total operating lease liabilities	$ 1,619,514

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - Subsequent Event [Member]	3 Months Ended
	Aug. 31, 2021USD ($)$ / sharesshares
SUBSEQUENT EVENTS (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares	1,500
Share-based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price | $ / shares	$ 2.68
Proceeds from Stock Options Exercised | $	$ 4,000
Stock Issued During Period, Shares, New Issues | shares	201,553
Share Price | $ / shares	$ 4.16
Proceeds from Issuance of Common Stock | $	$ 824,000

RESTATEMENT OF PREVIOUSLY ISS_3

RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details) - USD ($)	May 31, 2021	Feb. 28, 2021	Nov. 30, 2020	Aug. 31, 2020	May 31, 2020	May 31, 2019
Revision of Prior Period, Adjustment [Member]
RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details) [Line Items]
Retained Earnings (Accumulated Deficit)	$ (2,151,567)	$ (1,935,493)	$ (1,650,262)	$ (1,417,328)	$ (1,174,349)	$ (836,232)
Additional Paid in Capital	2,151,567	1,935,493	1,650,262	1,417,328	1,174,349	836,232
Previously Reported [Member]
RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details) [Line Items]
Retained Earnings (Accumulated Deficit)	(28,394,768)	(26,899,621)	(25,060,311)	(23,575,147)	(21,925,732)	(19,586,678)
Additional Paid in Capital	36,685,176	36,563,562	35,284,864	35,231,415	35,213,707	22,830,006
Restatement of the Company's Financial Statements [Member]
RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details) [Line Items]
Retained Earnings (Accumulated Deficit)	(30,546,335)	(28,835,114)	(26,710,573)	(24,992,475)	(23,100,081)	(20,422,910)
Additional Paid in Capital	$ 38,836,743	$ 38,499,055	$ 36,935,126	$ 36,648,743	$ 36,388,056	$ 23,666,238

RESTATEMENT OF PREVIOUSLY ISS_4

RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details) - RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS - USD ($)	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Feb. 28, 2021	Nov. 30, 2020	Aug. 31, 2020	Nov. 30, 2020	Feb. 28, 2021	May 31, 2021	May 31, 2020	May 31, 2019
Previously Reported [Member]
Shareholders' Equity:
Additional paid-in-capital	$ 36,563,562	$ 35,284,864	$ 35,231,415	$ 35,284,864	$ 36,563,562	$ 36,685,176	$ 35,213,707	$ 22,830,006
Accumulated deficit	(26,899,621)	(25,060,311)	(23,575,147)	(25,060,311)	(26,899,621)	(28,394,768)	(21,925,732)	(19,586,678)
Other Equity accounts			924,357	924,228	935,642	936,615	925,078	737,642
Total Shareholders' Equity	10,599,583	11,148,781	12,580,625	11,148,781	10,599,583	9,227,023	14,213,053	3,980,970
Cost of sales	3,667,143	1,011,030	960,930	1,971,960	5,639,103	6,702,046	4,910,935
Gross Profit (Loss)	(38,505)	361,496	182,876	544,372	505,867	496,981	1,781,776
Operating Expenses:
Selling, general and administrative	1,278,393	1,254,847	1,164,564	2,419,411	3,697,804	4,608,950	2,274,415
Research and development	563,216	586,403	674,693	1,261,096	1,824,312	2,410,506	1,910,209
Total operating expense	1,841,609	1,841,250	1,839,257	3,680,507	5,522,116	7,019,456	4,184,624
Loss from operations	(1,880,114)	(1,479,754)	(1,656,381)	(3,136,135)	(5,016,249)	(6,522,475)	(2,402,848)
Loss before income taxes	(1,842,427)	(1,471,771)	(1,648,290)	(3,120,061)	(4,962,488)	(6,455,979)	(2,331,664)
Net loss	$ (1,839,310)	$ (1,485,164)	$ (1,649,415)	$ (3,134,579)	$ (4,973,889)	$ (6,469,036)	$ (2,339,054)
Basic net loss per common share (in Dollars per share)	$ (0.15)	$ (0.13)	$ (0.14)	$ (0.27)	$ (0.42)	$ (0.54)	$ (0.23)
Diluted net loss per common share (in Dollars per share)	$ (0.15)	$ (0.13)	$ (0.14)	$ (0.27)	$ (0.42)	$ (0.54)	$ (0.23)
Comprehensive loss	$ (1,844,747)	$ (1,486,694)	$ (1,651,136)	$ (3,137,829)	$ (4,982,576)	$ (6,477,151)	$ (2,342,364)
Cash flows from operating activities:
Net loss	(1,839,310)	(1,485,164)	(1,649,415)	(3,134,579)	(4,973,889)	(6,469,036)	(2,339,054)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option expense			3,808	24,227	261,176	377,391	200,470
Net cash used in operating activities			(1,597,146)	(2,880,218)	(4,244,064)	(5,251,748)	(4,297,498)
Cash and cash equivalents at end of year	5,272,565	5,683,787	6,964,314	5,683,787	5,272,565	4,199,311	8,641,027
Revision of Prior Period, Adjustment [Member]
Shareholders' Equity:
Additional paid-in-capital	1,935,493	1,650,262	1,417,328	1,650,262	1,935,493	2,151,567	1,174,349	836,232
Accumulated deficit	(1,935,493)	(1,650,262)	(1,417,328)	(1,650,262)	(1,935,493)	(2,151,567)	(1,174,349)	(836,232)
Other Equity accounts
Total Shareholders' Equity
Cost of sales	34,926	52,777	64,787	117,564	152,490	130,696	43,549
Gross Profit (Loss)	(34,926)	(52,777)	(64,787)	(117,564)	(152,490)	(130,696)	(43,549)
Operating Expenses:
Selling, general and administrative	249,554	149,999	141,380	291,379	540,933	785,575	272,207
Research and development	751	30,158	36,812	66,970	67,721	60,947	22,361
Total operating expense	250,305	180,157	178,192	358,349	608,654	846,522	294,568
Loss from operations	(285,231)	(232,934)	(242,979)	(475,913)	(761,144)	(977,218)	(338,117)
Loss before income taxes	(285,231)	(232,934)	(242,979)	(475,913)	(761,144)	(977,218)	(338,117)
Net loss	$ (285,231)	$ (232,934)	$ (242,979)	$ (475,913)	$ (761,144)	$ (977,218)	$ (338,117)
Basic net loss per common share (in Dollars per share)	$ (0.03)	$ (0.02)	$ (0.02)	$ (0.04)	$ (0.07)	$ (0.08)	$ (0.03)
Diluted net loss per common share (in Dollars per share)	$ (0.03)	$ (0.02)	$ (0.02)	$ (0.04)	$ (0.07)	$ (0.08)	$ (0.03)
Comprehensive loss	$ (285,231)	$ (232,934)	$ (242,979)	$ (475,913)	$ (761,144)	$ (977,218)	$ (338,117)
Cash flows from operating activities:
Net loss	(285,231)	(232,934)	(242,979)	(475,913)	(761,144)	(977,218)	(338,117)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option expense			242,979	475,913	761,144	977,218	338,117
Net cash used in operating activities
Cash and cash equivalents at end of year
Restatement of the Company's Financial Statements [Member]
Shareholders' Equity:
Additional paid-in-capital	38,499,055	36,935,126	36,648,743	36,935,126	38,499,055	38,836,743	36,388,056	23,666,238
Accumulated deficit	(28,835,114)	(26,710,573)	(24,992,475)	(26,710,573)	(28,835,114)	(30,546,335)	(23,100,081)	(20,422,910)
Other Equity accounts			924,357	924,228	935,642	936,615	925,078	737,642
Total Shareholders' Equity	10,599,583	11,148,781	12,580,625	11,148,781	10,599,583	9,227,023	14,213,053	$ 3,980,970
Cost of sales	3,702,069	1,063,807	1,025,717	2,089,524	5,791,593	6,832,742	4,954,484
Gross Profit (Loss)	(73,431)	308,719	118,089	426,808	353,377	366,285	1,738,227
Operating Expenses:
Selling, general and administrative	1,527,947	1,404,846	1,305,944	2,710,790	4,238,737	5,394,525	2,546,622
Research and development	563,967	616,561	711,505	1,328,066	1,892,033	2,471,453	1,932,570
Total operating expense	2,091,914	2,021,407	2,017,449	4,038,856	6,130,770	7,865,978	4,479,192
Loss from operations	(2,165,345)	(1,712,688)	(1,899,360)	(3,612,048)	(5,777,393)	(7,499,693)	(2,740,965)
Loss before income taxes	(2,127,658)	(1,704,705)	(1,891,269)	(3,595,974)	(5,723,632)	(7,433,197)	(2,669,781)
Net loss	$ (2,124,541)	$ (1,718,098)	$ (1,892,394)	$ (3,610,492)	$ (5,735,033)	$ (7,446,254)	$ (2,677,171)
Basic net loss per common share (in Dollars per share)	$ (0.18)	$ (0.15)	$ (0.16)	$ (0.31)	$ (0.49)	$ (0.62)	$ (0.26)
Diluted net loss per common share (in Dollars per share)	$ (0.18)	$ (0.15)	$ (0.16)	$ (0.31)	$ (0.49)	$ (0.62)	$ (0.26)
Comprehensive loss	$ (2,129,978)	$ (1,719,628)	$ (1,894,115)	$ (3,613,742)	$ (5,743,720)	$ (7,454,369)	$ (2,680,481)
Cash flows from operating activities:
Net loss	(2,124,541)	(1,718,098)	(1,892,394)	(3,610,492)	(5,735,033)	(7,446,254)	(2,677,171)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option expense			246,787	500,140	1,022,320	1,354,609	538,587
Net cash used in operating activities			(1,597,146)	(2,880,218)	(4,244,064)	(5,251,748)	(4,297,498)
Cash and cash equivalents at end of year	$ 5,272,565	$ 5,683,787	$ 6,964,314	$ 5,683,787	$ 5,272,565	$ 4,199,311	$ 8,641,027