EXHIBIT 5.1
                                                                     -----------

                [LETTERHEAD OF PRYOR CASHMAN SHERMAN & FLYNN LLP]

                                               December 22, 1999

NexMed, Inc.
350 Corporate Boulevard
Robbinsville, New Jersey  08691


Ladies and Gentlemen:

         We are acting as counsel to NexMed, Inc., a Nevada corporation (the
"Company"), in connection with the Registration Statement on Form S-8, File No.
333-______ (the "Registration Statement"), as filed by the Company with the
Securities and Exchange Commission with respect to the registration under the
Securities Act of 1933, as amended (the "Act"), of 4,580,000 shares (the
"Shares") of common stock, par value $0.001 per share, for delivery under the
Company's Non-Qualified Performance Incentive Program, Non-Qualified Stock
Option Plan, Stock Option and Long Term Incentive Compensation Plan and
Recognition and Retention Stock Incentive Plan (collectively, the "Plans").

         We are qualified to practice law in the State of New York. We express
no opinion as to, and, for the purposes of the opinion set forth herein, we have
conducted no investigation of, and do not purport to be experts on, any laws
other than the laws of the State of New York, the Nevada General Corporation Law
and the federal securities laws of the United States of America.

         We have examined such documents as we considered necessary for the
purposes of this opinion. Based on such examination, it is our opinion that the
Shares have been duly authorized and, upon issuance in accordance with the
Plans, will be legally issued, fully-paid and non-assessable under the laws of
the State of Nevada.

         We consent to the use of this opinion as an exhibit to the Registration
Statement.

         This opinion is furnished in connection with the transactions covered
hereby. This opinion may not be relied upon by you for any other purpose, or
furnished to, quoted to, or relied upon by any other person, firm or corporation
for any purpose, without prior written consent.

                                         Very truly yours,

                                         /s/ Pryor Cashman Sherman & Flynn LLP