- ----------------------------------------------------------------------------


                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                    FORM 10-Q
         --------------------------------------------------------------


              [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                For the quarterly period ended September 30, 1999
                                       OR

             [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OR THE SECURITIES EXCHANGE ACT OF 1934
                 For the transition period from______ to_______

                          Commission file number 1-9114

                             MYLAN LABORATORIES INC.
             (Exact Name of registrant as specified in its charter)

                  Pennsylvania                         25-1211621
         (State or other jurisdiction of             (I.R.S. Employer
          incorporation or organization)             Identification No.)

                  130 Seventh Street
             1030 Century Building
            Pittsburgh, Pennsylvania                        15222
   (Address of principal executive offices)                (Zip Code)

                                  412-232-0100
              (Registrant's telephone number, including area code)

                                 Not Applicable
         (Former name, former address and former fiscal year, if changed
          since last report)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding  twelve months (or for such shorter period that the Registrant was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days:

                           YES   X                            NO

Indicate the number of shares  outstanding  of each of the  issuer's  classes of
common stock, as of the latest practicable date

                                                          Outstanding at
   Class of Common Stock                                 October 28, 1999
   ---------------------                                 ----------------
     $.50 par value                                         129,229,715
- ---------------------------------------------------------------------------









                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                    ----------------------------------------

                                      INDEX
                                      -----



                                                                    Page
                                                                   Number
                                                                  --------
PART I. FINANCIAL INFORMATION

        ITEM 1: Financial Statements

           Consolidated Statements of Earnings - Three and
             Six Months Ended September 30, 1999 and 1998             2

           Consolidated Balance Sheets - September 30, 1999
             and March 31, 1999                                       3

           Consolidated Statements of Cash Flows - Six
             Months Ended September 30, 1999 and 1998                 4

           Notes to Consolidated Financial Statements -
             Six Months Ended September 30, 1999                    5 - 9

        ITEM 2:       Management's Discussion and Analysis of
                      Financial Condition and Results of
                      Operations                                   10 - 16

        ITEM 3: Quantitative and Qualitative Disclosures
                      About Market Risk                              16

PART II. OTHER INFORMATION

        ITEM 1: Legal Proceedings                                  16 - 18

        ITEM 4: Submission of Matters to a Vote of
                      Security Holders                               19

        ITEM 6: Exhibits and Reports on Form 8-K                     19


SIGNATURES                                                           19








                                MYLAN LABORATORIES INC. AND SUBSIDIARIES
                                   CONSOLIDATED STATEMENTS OF EARNINGS
                                 (In thousands except per share amounts)

                                             UNAUDITED

                                                 Three Months Ended          Six Months Ended
                                                   September 30,               September 30,
                                                 ----------------             ---------------

                                               1999          1998           1999          1998
                                            ----------    ----------      ---------     --------
                                                                           
NET SALES                                    $194,489       $177,592      $371,584       $344,310

COST AND EXPENSES:
        Cost of Sales                          83,677         85,548       164,525        167,112
        Research and Development               11,473         13,382        23,264         27,466
        Selling and Administrative             38,880         28,435        76,994         53,444
                                            ---------    -----------      --------      ---------
                                              134,030        127,365       264,783        248,022

EQUITY IN (LOSS) EARNINGS OF SOMERSET            (989)         2,142        (1,071)         4,492

OTHER (EXPENSE) INCOME                         (1,097)         4,078         2,762          8,112
                                             --------    -----------     ---------      ---------
EARNINGS BEFORE INCOME TAXES                   58,373         56,447       108,492        108,892
INCOME TAXES                                   21,307         19,232        39,473         37,495
                                            ---------    -----------     ---------      ---------
NET EARNINGS                                 $ 37,066       $ 37,215      $ 69,019       $ 71,397
                                            =========    ===========     =========      =========
EARNINGS PER COMMON SHARE:
  Basic                                      $    .29       $    .30      $    .53       $    .58
                                            =========    ===========     =========      =========
  Diluted                                    $    .28       $    .30      $    .53       $    .58
                                            =========    ===========     =========      =========
WEIGHTED AVERAGE COMMON SHARES:
  Basic                                       129,182        122,408       129,159        122,352
                                            =========    ===========     =========      =========
  Diluted                                     130,144        123,809       130,227        123,943
                                            =========    ===========     =========      =========

    The Company has paid regular quarterly cash dividends of $.04 per share since October 1995.

                    See Notes to Consolidated Financial Statements

                                      -2-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                           CONSOLIDATED BALANCE SHEETS
                     (In thousands except share information)

                                    UNAUDITED

                                     ASSETS




                                                            September 30,     March 31,
                                                                  1999          1999
                                                                 ------        ------
                                                                    
Current Assets:
    Cash and cash equivalents                                 $  232,784    $  189,849
    Marketable securities                                         61,297        69,872
    Accounts receivable - net                                    162,419       148,896
    Inventories:
        Raw materials                                             66,058        57,414
        Work in process                                           23,812        20,813
        Finished goods                                            49,974        58,266
                                                              ----------    ----------
                                                                 139,844       136,493
    Deferred income tax benefit                                   27,120        18,199
    Other current assets                                          16,376        19,650
                                                             -----------    ----------
           Total Current Assets                                  639,840       582,959


Property, Plant and Equipment - at cost                          257,307       244,793
    Less accumulated depreciation                                 98,054        90,157
                                                             -----------    ----------
                                                                 159,253       154,636
Investment in and Advances to Somerset                            32,800        34,114
Intangible Assets - net of accumulated amortization              330,191       336,003
Other Assets                                                      97,744        98,949
                                                            ------------    ----------
Total Assets                                                  $1,259,828    $1,206,661
                                                            ============    ==========

   LIABILITIES AND SHAREHOLDERS' EQUITY

Current Liabilities:
    Trade accounts payable                                   $   17,092     $   12,142
    Current portion of long-term obligations                     15,417         16,941
    Cash dividend payable                                         5,185          5,178
    Other current liabilities                                    49,708         62,100
                                                             ----------     ----------
           Total Current Liabilities                             87,402         96,361

Long-Term Obligations                                            24,052         26,827
Deferred Income Tax Liability                                    27,283         23,568
Shareholders' Equity:
    Preferred stock, par value $.50 per share, authorized
      5,000,000 shares, issued and outstanding - none                 -              -
    Common stock, par value $.50 per share, authorized
      300,000,000 shares, issued 130,083,792 shares at
      September 30, 1999 and 129,968,514 shares at
      March 31, 1999                                             65,042         64,984
    Additional paid-in capital                                  313,527        311,995
    Retained earnings                                           748,688        690,003
    Accumulated other comprehensive income                       2,016           1,105
                                                            -----------     ----------
                                                              1,129,273      1,068,087
    Less treasury stock - at cost, 888,578 shares at
      September 30, 1999 and March 31, 1999                       8,182          8,182
                                                            -----------     ----------
      Total Shareholders' Equity                              1,121,091      1,059,905
                                                             ----------     ----------
Total Liabilities and Shareholders' Equity                   $1,259,828     $1,206,661
                                                            ===========     ==========

                 See Notes to Consolidated Financial Statements

                                       -3-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                      CONSOLIDATED STATEMENTS OF CASH FLOWS
              FOR THE SIX MONTHS ENDED SEPTEMBER 30, 1999 AND 1998
                                 (In thousands)

                                    UNAUDITED


                                                             1999         1998
                                                             ----         ----
CASH FLOWS FROM OPERATING ACTIVITIES
    Net earnings                                         $ 69,019     $ 71,397
    Adjustments to reconcile net earnings to net
        cash provided from operating activities:
          Depreciation and amortization                    17,866       11,154
           Deferred income tax benefit                     (5,904)      (4,716)
           Equity in the loss(earnings)of Somerset          1,071      (4,492)
           Cash received from Somerset                        243          585
       Allowances on accounts receivable                   23,338        8,287
       Other noncash expense                               10,402          323
        Changes in operating assets and liabilities:
           Accounts receivable                            (36,861)     (29,041)
           Inventories                                     (3,225)      (5,181)
           Trade accounts payable                           4,950      (2,626)
           Other operating assets and liabilities         (12,510)       11,203
                                                         --------      --------
Net cash provided from operating activities                68,389       56,893

CASH FLOWS FROM INVESTING ACTIVITIES
    Additions to property, plant and equipment            (12,514)      (8,104)
    Increase in intangible and other assets                (8,632)      (3,084)
    Proceeds from investment securities                    95,985       13,853
    Purchase of investment securities                     (85,528)     (11,995)
                                                         --------     --------
Net cash used in investing activities                     (10,689)      (9,330)
CASH FLOWS FROM FINANCING ACTIVITIES
    Payments on long-term obligations                      (6,028)      (6,139)
    Cash dividends paid                                   (10,327)      (9,781)
  Proceeds from exercise of stock options                   1,590        2,824
                                                         --------     --------
Net cash used in financing activities                     (14,765)     (13,096)

Net Increase in Cash and Cash Equivalents                  42,935       34,467
Cash and cash equivalents - beginning of period           189,849      103,756
                                                         --------     --------
Cash and cash equivalents - end of period                $232,784     $138,223
                                                         ========     ========
CASH PAID DURING THE PERIOD FOR:
    Interest                                             $    542     $    275
                                                         ========     ========
    Income Taxes                                         $ 47,168     $ 38,329
                                                         ========     ========


                 See Notes to Consolidated Financial Statements



                                       -4-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                SIX MONTHS ENDED
                               SEPTEMBER 30, 1999

                                    Unaudited

A.   In  the  opinion  of  management,   the  accompanying  unaudited  financial
     statements  contain all  adjustments  (consisting of only normal  recurring
     accruals)  necessary  to present  fairly the  financial  position  of Mylan
     Laboratories  Inc. and  subsidiaries  (the  "Company")  as of September 30,
     1999, and March 31, 1999,  together with the results of operations and cash
     flows for the  interim  periods  ended  September  30,  1999 and 1998.  The
     consolidated  results  of  operations  for the three and six  months  ended
     September  30, 1999,  are not  necessarily  indicative of the results to be
     expected for the full year.

B.   These interim  financial  statements should be read in conjunction with the
     consolidated  financial  statements and notes thereto in the Company's 1999
     Annual Report and Report on Form 10-K.

C.   Diluted  earnings  per common  share is computed by dividing  net  earnings
     available to common  shareholders  by the weighted  average  common  shares
     outstanding  adjusted for the dilutive  effect of options granted under the
     Company's  stock option plans.  The effect of dilutive stock options on the
     weighted  average common shares  outstanding  was 962,000 and 1,401,000 for
     the three months  ending  September  30, 1999 and 1998,  and  1,068,000 and
     1,591,000 for the six months ending September 30, 1999 and 1998.

D.   Total comprehensive income for the three and six months ended September 30,
     1999 and 1998, are as follows: (in thousands)

                                  Three Months Ended      Six Months Ended
                                      September 30,          September 30,
                                      -------------          -------------
                                     1999        1998       1999       1998
                                     ----        ----       ----       ----

Net earnings                        $37,066     $37,215    $69,019    $71,397
Other comprehensive income, net
of tax:

  Unrealized gain(loss) on
    marketable securities             2,883        (454)     3,385     (1,849)
  Adjustment for gains
    included in net earnings         (2,439)        (94)    (2,474)      (191)
                                    -------     -------    -------   --------
Comprehensive income                $37,510     $36,667    $69,930    $69,357
                                    =======     =======   ========   ========

Accumulated  other  comprehensive  income, as reflected on the balance sheet, is
comprised  solely  of the  unrealized  gain  on  marketable  securities,  net of
deferred income taxes.

                                       -5-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                SIX MONTHS ENDED
                               SEPTEMBER 30, 1999

                                    Unaudited

E.   The following  table  presents the  comparative  operating  results for the
     Company's operating segments: (in thousands)


                            Three Months Ended          Six Months Ended
                              September 30,               September 30,
                             ---------------             ---------------

                            1999          1998          1999        1998
                            ----          ----          ----        ----
  Generic Segment:
    Net Sales             $163,814      $161,529      $315,751    $314,333
    Segment Profit          68,535        56,016       127,752     108,159

  Branded Segment:
    Net Sales             $ 30,675      $ 16,063      $ 55,833    $ 29,977
    Segment Profit           5,483         3,947         7,184       6,007

  Corporate Expenses      $(15,645)     $(3,516)      $(26,444)   $ (5,274)

  Consolidated:
    Net Sales             $194,489      $177,592      $371,584    $344,310

  Pretax Earnings           58,373        56,447       108,492     108,892


     Segment net sales  represents  sales to unrelated  third  parties.  Segment
     profit   represents   segment   gross  profit  less  direct   research  and
     development,  sales and marketing and  administrative  expenses.  Corporate
     expenses  include legal costs,  amortization  of goodwill,  other corporate
     administrative expenses and nonoperating income and expense.

F.   A subsidiary of the Company is involved in a dispute  relating to a license
     and  supply  contract  for  nitroglycerin  transdermal  patches  which both
     parties  claim has been  breached  by the other.  The other  company  seeks
     damages  in excess of  $20,000,000.  The  dispute  is  subject  to  binding
     arbitration  in which  the  hearing  phase is now  complete.  Although  the
     Company believes that the claims against it are without merit, there can be
     no assurance that the Company will prevail in this matter.

     The Company is  currently  involved  in  negotiations  with a state  agency
     concerning  certain  contract  pricing  matters.  Management  believes  the
     resolution  of this matter will not have a material  adverse  effect on the
     Company's operations or its financial position.


                                       -6-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                SIX MONTHS ENDED
                               SEPTEMBER 30, 1999
                                    Unaudited

F.   (cont.) The Company had an agreement with Genpharm Inc.  ("Genpharm") where
     it benefitted from the sale of ranitidine HCl tablets by Novopharm  Limited
     ("Novopharm")  under a separate  agreement  between Genpharm and Novopharm.
     Based  on an  independent  audit,  Genpharm  initiated  a  lawsuit  against
     Novopharm to resolve contract  interpretation issues and collect additional
     funds due. In response to Genpharm's  suit,  Novopharm filed  counterclaims
     against  both  Genpharm  and  the  Company   claiming   damages  of  up  to
     $60,000,000.  The Company believes the  counterclaims  against Genpharm and
     the Company are without merit and will vigorously defend its position.

     In June 1998,  the  Company  filed suit in the Los Angeles  Superior  Court
     against  VivoRx,   Inc.,  VivoRx  Diabetes,   Inc.  and  certain  directors
     (collectively  referred to as  "VivoRx").  In March 1999,  VivoRx  filed an
     answer to and  cross-complaint  in Los Angeles  Superior  Court against the
     Company.

     In  October  1999,  with  respect  to the  above  litigation  and a related
     arbitration  award,  the  Company  and  VivoRx  entered  into a  settlement
     agreement in which all claims and disputes have been resolved.  The Company
     accepted  title to an office  building  in  California,  subject to certain
     leasing  and  buyback  options  held by  VivoRx,  in  consideration  of the
     Company's  discharge of $18,000,000  due from VivoRx and the release by the
     Company  of  its  security   interest  in  certain  VivoRx  U.S.   patents.
     Additionally,  VivoRx was  granted an option to  repurchase  the common and
     preferred stock  currently  owned by the Company for  $15,000,000  over the
     next five years.  Upon the occurrence of certain events,  as defined in the
     settlement  agreement,  VivoRx  must  repurchase  such  stock or a  portion
     thereof.

     In addition to the litigation  involving  VivoRx, in June 1998, the Company
     filed suit in the Los Angeles Superior Court against associated  companies:
     American Bioscience,  Inc. ("ABI"),  American Pharmaceutical Partners, Inc.
     ("APP") and certain of their directors and officers. This litigation is not
     part of the prior  mentioned  settlement.  The Company's suit seeks various
     equitable remedies, including but not limited to, appointment of a receiver
     over  and  dissolution  of ABI and  APP,  injunctive  relief  to  stop  the
     misappropriation  of the Company's  research funding and equity  investment
     and the misappropriation of assets and personnel.  The Los Angeles Superior
     Court issued a  preliminary  injunction  order which,  among other  things,
     prohibits the defendants from  transferring or disposing of funds,  assets,
     technology or property without the

                                       -7-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                SIX MONTHS ENDED
                               SEPTEMBER 30, 1999

                                    Unaudited

F.   (cont.) Company's consent or commingling  assets,  property,  technology or
     personnel  with those of  VivoRx.  In June 1999,  the  defendants  filed an
     answer to and  cross-complaint  against the  Company.  The  cross-complaint
     alleges violations of California State laws,  interference with contractual
     relations and prospective  economic advantage,  fraud,  slander,  libel and
     other allegations.  The cross-  complainants seek unspecified  compensatory
     and punitive damages. The Company believes the cross-complaints are without
     merit and intends to vigorously defend its position.

     On December 22, 1998,  the Federal Trade  Commission  ("FTC") filed suit in
     U.S.  District Court for the District of Columbia (the "Court") against the
     Company.  The FTC's  complaint  alleges the Company engaged in restraint of
     trade,   monopolization,   attempted   monopolization   and  conspiracy  to
     monopolize,  arising out of certain agreements  involving the supply of raw
     materials used to manufacture two drugs. The FTC also sued in the same case
     the foreign  supplier of the raw materials,  the supplier's  parent company
     and its  United  States  distributor.  Under  the  terms of the  agreements
     related to these raw materials,  the Company has agreed to indemnify  these
     parties.

     The Company is a party to other suits involving the Attorneys  General from
     33 states and more than 20  putative  class  actions  that  allege the same
     conduct  alleged  in the FTC suit as well as  alleged  violations  of state
     consumer protection laws. A qui tam action was commenced by a private party
     in the U.S.  District Court for the District of South Carolina  purportedly
     on behalf of the United States alleging  violations of the False Claims Act
     and other statutes.

     The relief  sought by the FTC  includes an  injunction  barring the Company
     from engaging in the challenged conduct, recision of certain agreements and
     disgorgement in excess of $120,000,000.

     The states and private  parties seek  similar  relief,  treble  damages and
     attorneys'  fees.  In  addition,  a class  action  suit was filed  alleging
     violations of federal  securities laws by the Company and certain directors
     and officers of the Company.  Without  specifying a dollar amount, the suit
     seeks compensatory damages.




                                       -8-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                SIX MONTHS ENDED
                               SEPTEMBER 30, 1999

                                    Unaudited

F.   (cont.)  The  Company  had filed  motions  to  dismiss  the FTC  complaint,
     significant  portions  of the State  Attorneys  General  complaint  and the
     federal  securities  case.  In July 1999,  the Court  denied the  Company's
     motion to dismiss the FTC complaint.  The Company filed a motion requesting
     the Court to certify its ruling with  respect to the  jurisdictional  issue
     for  expedited  appeal to the U.S.  Court of Appeals  for the  District  of
     Columbia.  This motion was denied.  The Court granted in part and denied in
     part the  Company's  motion to  dismiss  portions  of the  State  Attorneys
     General  complaint.  In so doing,  the Court  limited  certain  theories of
     recovery  asserted by the states.  Some States have filed a motion with the
     Court requesting that it reconsider certain claims that were dismissed. The
     Company's  motions to  dismiss  the  federal  securities  case and  various
     private actions remain pending.

     The Company believes that it has meritorious  defenses to the claims in all
     remaining suits and intends to vigorously defend them. Although the Company
     believes it has  meritorious  defenses to the claims,  an adverse result in
     these suits could have a material adverse effect on the Company's financial
     position and results of its operations.



















                                       -9-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES
                         PART 1 - FINANCIAL INFORMATION

ITEM 2 - MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS
- -------------------------------------------------------------------------------
Introduction
- -------------
     Net earnings for the quarter ended  September 30, 1999,  were $37.1 million
or $.28 per share compared to $37.2 million or $.30 per share for the same prior
year period. Net earnings for the six month period then ended were $69.0 million
or $.53 per share compared to $71.4 million or $.58 per share for the same prior
year  period.  The Company  experienced  record sales for both the three and six
month  periods  ended  September  30, 1999,  due in part to the  acquisition  of
Penederm Inc. in October 1998. While sales and gross profits exceeded prior year
levels, higher operating expenses due to the inclusion of Penederm, expansion of
the  Company's  branded  sales force and increased  legal  expenses  resulted in
relatively unchanged operating income on a year-to-year comparison.

     All references to per share amounts in Item 2 are based on diluted weighted
average common shares.

     The following  table  presents the  comparative  operating  results for the
Company's operating segments: (dollars in millions)


                              Three Months Ended            Six Months Ended
                                 September 30,                September 30,
                                ---------------              ---------------


                          1999      1998  % Change      1999     1998  % Change
                          ----      ----  --------      ----     ----  --------
  Generic Segment:
    Net Sales            $163.9    $161.5    1%        $315.8   $314.3     0%
    Gross Profit           89.0      81.6    9%         168.4    158.2     6%
    Segment Profit         68.5      56.0   22%         127.7    108.2    18%
  Branded Segment:
    Net Sales            $ 30.6    $ 16.1   90%        $ 55.8   $ 30.0    86%
    Gross Profit           21.8      10.4  110%          38.7     19.0   104%
    Segment Profit          5.5       3.9   41%           7.2      6.0    20%
  Corporate Expenses    $ (15.6)   $ (3.5)             $(26.4)  $ (5.3)
  Consolidated:
    Net Sales            $194.5    $177.6   10%        $371.6   $344.3     8%
    Gross Profit          110.8      92.0   20%         207.1    177.2    17%
    Pretax Earnings        58.4      56.4    4%         108.5    108.9     0%


                                      -10-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

     The  Generic   Segment   includes  Mylan   Pharmaceuticals   Inc.  and  UDL
Laboratories.  The Branded  Segment  includes  Bertek  Pharmaceuticals  Inc. and
Penederm Inc.  Segment net sales  represents  sales to unrelated  third parties.
Segment gross profit represents  segment net sales less the corporate wide costs
of manufacturing,  warehousing and shipping associated with such sales.  Segment
profit  represents  segment gross profit less direct  research and  development,
sales and marketing and  administrative  expenses.  Corporate  expenses  include
legal costs,  amortization of goodwill,  other corporate administrative expenses
and nonoperating income and expenses.

Results of Operations
- ---------------------
Net Sales and Gross Profit

     Net sales for the three  months  ended  September  30,  1999,  were  $194.5
million  compared to $177.6 million for the same prior year period,  an increase
of 10%.  Net sales for the six months  ended  September  30,  1999,  were $371.6
million  compared to $344.3 million for the same prior year period,  an increase
of 8%.  The  increase  in sales  for both the three  and six  month  periods  is
primarily attributable to growth in the Branded Segments which includes sales of
products acquired in the Penederm transaction.

     Sales of generic products remain relatively unchanged as new products along
with the  Company's  initiative  of  selectively  raising  prices  offset  price
deterioration  on other generic  products.  Total generic volume was 2.1 billion
units for the quarter ended September 30, 1999, an increase of 10% over the same
prior year period and 4.1 billion  units for the current year six month  period,
an increase of 5% over the same prior year period.

     Gross  profits  increased  $18.9  million  over the prior year three  month
period to $110.8 million and $29.9 million to $207.1 million over the prior year
six month  period.  Gross  margins  (gross  profit as a  percent  of net  sales)
increased  to 57% from 52% and 56% from 51% for these  same  three and six month
periods.  The overall  increase in gross margins is attributable to increases in
both the branded  and  generic  gross  margins  and the  additional  increase in
branded  sales.  The  increase  in generic  margins  resulted  from the  Company
selectively  increasing  prices in prior  quarters  and the  reduction in profit
sharing  payments on certain  products.  The increase in branded  gross  margins
resulted from  increased  sales of higher  margin  products  including  products
acquired in the Penederm transaction.




                                      -11-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

Research and Development

     Expenditures  for  research  and  development  were $11.5  million  for the
quarter  ended  September  30, 1999,  and $23.3  million for the six months then
ended.  The  current  three and six month  periods  include  approximately  $2.1
million and $4.2 million in charges for dermatology related projects incurred by
Penederm and charged to the Branded Segment.  All other research and development
costs are charged to the Generic Segment.

     In the quarter ended June 30, 1999, the Company  terminated  funding to its
diabetes project with VivoRx Inc. This has temporarily  reduced  expenditures in
the  current  periods.  As  current  projects  enter  into  advanced  stages  of
development and additional  projects are initiated the Company expects  research
and development expenses to increase.

     The Company is actively pursuing joint development projects in an effort to
broaden its scope of capabilities in bringing to market new innovative products.
Such  arrangements  generally  provide for payments by the Company only upon the
attainment of certain  milestones.  While such  arrangements  help to reduce the
Company's financial risk for unsuccessful projects, attainment of milestones may
result in fluctuations in quarterly research and development expenses.

Selling and Administrative Expenses

     Selling and administrative expenses were $38.9 million for the three
months ended  September 30, 1999,  compared to $28.4 million for the same period
in the prior year.  Expenses for the six months ended  September 30, 1999,  were
$77.0 million compared to $53.4 million for the same period in the prior year.

     Corporate  administrative expenses were $13.5 million and $28.1 million for
the  current  three and six month  periods  compared  to $9.7  million and $17.9
million for the comparable  prior periods.  The increases over the prior periods
are  attributable  to higher goodwill  amortization  resulting from the Penederm
acquisition and higher legal expenses primarily related to the FTC litigation.

     Branded Segment selling and administrative  expenses were $14.2 million and
$27.2  million  for the  current  three and six month  periods  compared to $6.4
million and $12.9 million for the comparable prior periods. The increase in both
periods  over the prior  year  periods  is  primarily  due to the  inclusion  of
Penederm,  $4.1 million and $7.9 million in the current  periods,  and the costs
associated with expanding the sales and support staff for the Branded Segment.


                                      -12-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

     Generic Segment selling and administrative  expenses were $11.2 million and
$21.7 million for the current three and six month periods, which were relatively
unchanged from the same prior year periods.

Equity in Earnings

     The equity in the loss of Somerset in the current periods was primarily the
result of lower sales due to generic  competition on  Eldepryl(R)  and increased
expenditures for research and  development.  Somerset  Pharmaceuticals,  Inc. is
continuing its research for alternative uses for Eldepryl(R),  which is expected
to result in continued losses in the near term.

Other Income

     During the current quarter the Company  recorded a loss on an investment it
has in a limited partnership. The loss of $8.5 million was partially offset by a
gain of $3.9 million on the partial sale of another investment.

Income Taxes

     The Company's effective tax rate was 36% for both the three and six month
periods ending  September 30, 1999. The increase from the prior year  comparable
periods is primarily the result of nondeductible goodwill amortization resulting
from the acquisition of Penederm.  The Company expects the tax rate to remain at
approximately the current level throughout fiscal year 2000.

Liquidity, Capital Resources and Financial Condition
- ------------------------------------------------------
     Working capital  increased from $486.6 million at March 31, 1999, to $552.4
million  at  September  30,  1999.  The  ratio  of  current  assets  to  current
liabilities  has  increased  from 6.0 to 1 at  March  31,  1999,  to 7.3 to 1 at
September  30,  1999.  The  increase  in working  capital of $65.8  million  was
primarily due to the Company's  net earnings.  In addition to net earnings,  net
cash  provided  from  operating  activities  was affected by changes in accounts
receivable  and its  related  allowance  accounts.  Based  on its  current  cash
management  program,  the Company  has  invested  additional  cash in short term
marketable  securities  in the past.  This has created the  increase in proceeds
received from  investment  securities and the subsequent  purchase of additional
marketable securities as reflected in the Statements of Cash Flows.





                                      -13-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

     The  Company  continues  to examine  opportunities  to expand its  business
through  product and company  acquisitions.  The  Company's  capital  resources,
financial  condition and results of operations  could be materially  impacted if
the Company were to complete one or more of such acquisitions.

     Although the Company believes it has meritorious  defenses to the claims in
the FTC and  related  suits,  an  adverse  result in these  suits  could  have a
material adverse effect on the Company's business and financial  condition,  due
to the size of the FTC's  disgorgement  claim and the  threat of treble  damages
sought by the states,  as well as possible  damages in the other related  suits.
The Company  expects to incur  substantial  costs in  defending  itself in these
actions.

Year 2000
- ---------
     The Company has  reviewed its critical  information  technology  ("IT") and
non-IT operating systems for Year 2000 ("Y2K") compliance. Y2K compliance refers
to the issue of systems and equipment  having date  sensitive  components  being
able to recognize  the year 2000.  On the basis of this review and the processes
described below, management believes that the costs of remediation and potential
losses  related  to Y2K  issues are  unlikely  to have a material  effect on the
Company's financial position, results of operations or cash flows.

     In assessing  potential Y2K issues,  the Company has taken or is taking the
following steps to address its IT and non-IT operating systems:

     o    Formed a project  team  across  functional  departments  to review and
          identify nonconforming systems.

     o    Communicated to employees throughout the Company to increase
           awareness of issues and activate the identification process.

     o    Identified critical IT and non-IT nonconforming  operating systems and
          developed a plan to bring these systems into compliance.

     o    Established  a  testing  program  to  ensure  that  such  systems  are
          compliant.

     o    Corresponded with customers, vendors, service suppliers and financial
           institutions to verify their readiness.

     o    Developed  contingency  plans where  practical  in the event of system
          failures.

     Because of the growth of the Company over the last several  years and prior
to the  formation  of the project  team,  the  Company  initiated  major  system
conversions  to  accommodate  the physical  expansion and increased  transaction
volume  associated  with this growth.  Many factors were  considered  during the
selection process. While Y2K compliance was one of the factors considered, other
factors were equally and significantly more important.  Any new systems selected
were  expected to be and are believed to be Y2K  compliant.  The Company has not
been required to spend, nor does it anticipate spending, significant incremental
funds to become Y2K compliant.



                                      -14-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

     The Company has completed  system  conversions  for all major operating and
financial systems.  All such systems have been certified by the vendor to be Y2K
compliant.  The  Company  has  completed  its own  testing on these  systems and
verified their Y2K compliance.

     Due to the upgrades and replacements of its computer systems to accommodate
its growth,  the Company has neither  delayed,  nor  anticipates  delaying,  any
significant information system projects prior to the year 2000.

     The project team continues to evaluate and update  contingency plans. These
plans  are  developed  based on  correspondence  with  customers,  vendors,  raw
material suppliers,  service suppliers and financial  institutions regarding the
status of their Y2K  readiness  and the  results  of  testing  performed  on the
Company's  internal  systems.  The Company has contacted all of its  significant
business partners. As part of this process and due to the critical nature of the
Company's  products,  the Company has also initiated steps to monitor customers'
orders and buying  patterns.  The  Company  has taken  these steps to ensure the
availability of its products to all its customers as the millennium approaches.

     While the project team continues to develop  contingency plans for the more
likely scenarios of possible business  interruptions,  there can be no assurance
that the project team will identify and develop successful contingency plans for
all of the business interruptions that could possibly occur.

     Management  believes that the Company has acted with appropriate  diligence
to address  potential Y2K issues.  The Company is,  however,  dependent on third
parties,  such  as its  customers,  vendors,  raw  material  suppliers,  service
suppliers which include energy,  water,  communication  and  transportation  and
financial  institutions,  to make  their own  systems  Y2K  compliant.  If these
entities fail to remedy their Y2K issues,  the Company could potentially  suffer
interruptions in its business operations.  These interruptions could potentially
delay  the  Company  in its  manufacturing  or  distribution  of some or all its
products for an  undeterminable  amount of time. In addition,  the Company could
experience the corruption of data in its own internal information systems.  Such
corruption could lead to temporary  interruptions  in certain isolated  business
operations.  These interruptions may or may not lead to an adverse impact on the
Company's overall business operations.











                                      -15-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

Forward-Looking Statements
- --------------------------
     The statements set forth in this Item 2 under Results of Operations
concerning  the  manner in which the  Company  intends  to  conduct  its  future
operations,  potential trends that may impact future results of operations,  and
its  beliefs  or  expectations  about  future  operations  are   forward-looking
statements. The Company may be unable to realize its plans and objectives due to
various important factors,  including, but not limited to, the factors described
under "Forward  Looking  Statements" in Item 7 of the Company's Annual Report on
Form 10-K for the year ended March 31, 1999,  and under "Year 2000" in this Item
2.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
- -------------------------------------------------------------------
     The  information  required by Item 3 has been  disclosed  in Item 7A of the
Company's 1999 Annual Report on Form 10-K.  There has been no material change in
the disclosure regarding market risk.

                           PART II. OTHER INFORMATION
                           --------------------------
ITEM 1. LEGAL PROCEEDINGS
- -------------------------
     Since the date of the filing of the  Company's  report on Form 10-Q for the
period  ended June 30, 1999,  there have been no material new legal  proceedings
involving the Company or any material  developments to such proceedings,  except
as described below.

     A subsidiary of the Company is involved in a dispute relating to a license
and supply  contract for  nitroglycerin  transdermal  patches which both parties
claim has been breached by the other.  The other company seeks damages in excess
of  $20,000,000.  The  dispute is subject  to binding  arbitration  in which the
hearing  phase is now  complete.  Although the Company  believes that the claims
against it are without  merit,  there can be no assurance  that the Company will
prevail in this matter.

     In June 1998,  the  Company  filed suit in the Los Angeles  Superior  Court
against VivoRx, Inc., VivoRx Diabetes,  Inc. and certain directors (collectively
referred  to as  "VivoRx").  In  March  1999,  VivoRx  filed  an  answer  to and
cross-complaint in Los Angeles Superior Court against the Company.

     In October 1999, with respect to the above litigation and a related
arbitration award, the Company and VivoRx entered into a settlement agreement in
which all claims and disputes have been resolved.  The Company accepted title to
an office building in California, subject to certain leasing and buyback options
held by VivoRx,  in consideration of the Company's  discharge of $18,000,000 due
from VivoRx and the release by the Company of its  security  interest in certain
VivoRx U.S.

                                      -16-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

patents. Additionally, VivoRx was granted an option to repurchase the common and
preferred stock  currently  owned by the Company for  $15,000,000  over the next
five years.  Upon the occurrence of certain events, as defined in the settlement
agreement, VivoRx must repurchase such stock or a portion thereof.

     In addition to the litigation  involving  VivoRx, in June 1998, the Company
filed suit in the Los  Angeles  Superior  Court  against  associated  companies:
American  Bioscience,  Inc.  ("ABI"),  American  Pharmaceutical  Partners,  Inc.
("APP") and certain of their directors and officers. This litigation is not part
of the prior mentioned  settlement.  The Company's suit seeks various  equitable
remedies,  including  but not limited  to,  appointment  of a receiver  over and
dissolution of ABI and APP,  injunctive relief to stop the  misappropriation  of
the Company's research funding and equity investment and the misappropriation of
assets and  personnel.  The Los  Angeles  Superior  Court  issued a  preliminary
injunction  order which,  among other  things,  prohibits  the  defendants  from
transferring or disposing of funds,  assets,  technology or property without the
Company's consent or commingling assets, property,  technology or personnel with
those  of  VivoRx.  In  June  1999,  the  defendants  filed  an  answer  to  and
cross-complaint against the Company.

     The   cross-complaint   alleges   violations  of  California   State  laws,
interference  with  contractual  relations and prospective  economic  advantage,
fraud,  slander,  libel  and  other  allegations.  The  cross-complainants  seek
unspecified   compensatory  and  punitive  damages.  The  Company  believes  the
cross-complaints  are  without  merit  and  intends  to  vigorously  defend  its
position.

     As  described  in the Form  10-K for the year  ended  March  31,  1999,  in
December 1998, the Federal Trade Commission  ("FTC") filed suit in U.S. District
Court for the District of Columbia (the "Court") against the Company.  The FTC's
complaint  alleges the Company  engaged in restraint  of trade,  monopolization,
attempted  monopolization  and conspiracy to monopolize,  arising out of certain
agreements  involving the supply of raw materials used to manufacture two drugs.
The FTC also sued in the same case the foreign  supplier  of the raw  materials,
the supplier's parent company and its United States distributor. Under the terms
of the  agreements  related to these raw  materials,  the  Company has agreed to
indemnify these parties.

     The Company is also a party to other suits involving the Attorneys  General
from 33 states and more than 20  putative  class  actions  that  allege the same
conduct alleged in the FTC suit as well as alleged  violations of state consumer
protection  laws. A qui tam action was  commenced by a private party in the U.S.
District Court for the District of South  Carolina  purportedly on behalf of the
United States  alleging  violations of the False Claims Act and other  statutes.
The relief sought


                                      -17-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

by the FTC  includes an  injunction  barring the  Company  from  engaging in the
challenged conduct, recision of certain agreements and disgorgement in excess of
$120,000,000.

     The states and private  parties seek  similar  relief,  treble  damages and
attorneys' fees. In addition,  a class action suit was filed alleging violations
of federal  securities laws by the Company and certain directors and officers of
the Company.  Without  specifying a dollar amount,  the suit seeks  compensatory
damages.

     The Company had filed  motions to dismiss  the FTC  complaint,  significant
portions of the State  Attorneys  General  complaint and the federal  securities
case.  In July 1999,  the Court denied the  Company's  motion to dismiss the FTC
complaint. The Company filed a motion requesting the Court to certify its ruling
with respect to the jurisdictional  issue for expedited appeal to the U.S. Court
of Appeals for the District of Columbia. This motion was denied.

     The  Court  granted  in part and  denied  in part the  Company's  motion to
dismiss  portions of the State Attorneys  General  complaint.  In so doing,  the
Court limited certain theories of recovery  asserted by the states.  Some States
have filed a motion with the Court requesting that it reconsider  certain claims
that were  dismissed.  The Company's  motions to dismiss the federal  securities
case, along with various private actions, remain pending.

     The Company believes that it has meritorious  defenses to the claims in all
FTC and related  suits and  intends to  vigorously  defend  them.  Although  the
Company believes it has meritorious defenses to the claims, an adverse result in
these  suits could have a material  adverse  effect on the  Company's  financial
position and results of its operations.

     The Company is involved in various other legal proceedings that are
considered  normal to its  business.  While it is not  feasible  to predict  the
ultimate outcome of such  proceedings,  it is the opinion of management that the
outcome of these suits will not have a material  adverse effect on the Company's
operations, financial position, or liquidity.









                                      -18-





                    MYLAN LABORATORIES INC. AND SUBSIDIARIES

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
- -----------------------------------------------------------
     On July 23, 1999, the annual meeting of the shareholders of the Company
was held. At this meeting,  the  shareholders  overwhelmingly  elected the seven
directors nominated and approved the appointment of Deloitte & Touche LLP as the
Company's  independent  auditors.  Additionally,  the  shareholders  approved  a
shareholder's proposal recommending that the Company redeem the rights under the
Company's  Shareholder  Rights Plan so as to eliminate the  continuing  director
provisions of the Plan.

ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K
- ----------------------------------------
     (a)  Exhibit 27 - Financial Data Schedule

     (b)  Reports on Form 8-K - There  were no reports on Form 8-K filed  during
          the three months ended September 30, 1999.


                                   SIGNATURES
                                   ----------
     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                           Mylan Laboratories Inc.
                                                (Registrant)


DATE 11/03/99                       /s/ Milan Puskar
     --------------                 ---------------------------
                                    Milan Puskar
                                    Chairman of the Board, Chief
                                    Executive Officer and President
                                    (Principal executive officer)


DATE 11/03/99                       /s/ Donald C. Schilling
     ----------------               ---------------------------
                                    Donald C. Schilling
                                    Vice President of Finance and
                                    Chief Financial Officer
                                    (Principal financial officer)







                             -19-