EXHIBIT 99.1

Press Release

( BW)(TX-ZONAGEN)(ZONA)(ZNG) Zonagen Informed That Vasomax Submission to be
Withdrawn in the United Kingdom

    Business Editors/Health & Medical Writers

    THE WOODLANDS, Texas--(BW HealthWire)--April 29, 2002--Zonagen, Inc.
(Nasdaq:ZONA)(PCX:ZNG) announced today that it has been informed by the
worldwide licensee of Vasomax(R) that the Marketing Authorization Application
for Vasomax(R) in the United Kingdom will be withdrawn. This decision was made
following a review of the comments received from the Committee on Safety of
Medicines regarding the Vasomax(R) submission. Vasomax(R) is Zonagen's oral
therapy for the treatment of erectile dysfunction.

    Joseph S. Podolski, President and CEO of Zonagen, said, "This is clearly a
setback for the Vasomax(R) program. Once we have been able to assess the
consequences of this action we will advise our shareholders."

    Zonagen, Inc. is engaged in the development of pharmaceutical products for
the reproductive system.

    Any statements that are not historical facts contained in this release such
as interpretation of data and/or potential approval of phentolamine for use in
the United Kingdom or elsewhere, are forward-looking statements that involve
risks and uncertainties, including but not limited to those relating to the
uncertainties involving the Company's early stage of development, clinical trial
results and FDA approval in the U.S. and approval of regulatory authorities in
other jurisdictions, substantial dependence on one product, history of operating
losses, future capital needs and uncertainty of additional funding, uncertainty
of protection for patents and proprietary technology, litigation, governmental
regulation, limited sales and marketing experience and dependence on
collaborators, manufacturing uncertainties and reliance on third parties,
competition and technology change, product liability and availability of
insurance, and other risks identified in the Company's Annual Report on Form
10-K for the year ended December 31, 2001, as filed with the Securities and
Exchange Commission.

Contact:
     Zonagen, Inc., The Woodlands
     Joseph S. Podolski, 281/719-3447