Contact:
Joe Podolski, President and CEO
podolski@zonagen.com
281-719-3447
FOR IMMEDIATE RELEASE


            ZONAGEN REPORTS PRELIMINARY RESULTS OF SELF TENDER OFFER

         (The Woodlands, Texas) - January 8, 2004 - Zonagen, Inc. (Nasdaq: ZONA)
announced today the preliminary results of its self tender offer, which expired
at 12:00 midnight, Eastern Standard Time, on January 7, 2004. Based on the
preliminary count by the depository for the tender offer, 6,834,455 shares of
common stock, including 60,888 shares issuable upon exercise of options tendered
by directors for repurchase, were properly tendered and not withdrawn. Zonagen
is accepting for purchase 6,834,455 shares at a purchase price of $2.10 per
share in accordance with the terms of the offer. As a result of the completion
of the tender offer, and immediately following payment for the tendered shares,
Zonagen will have approximately 4.7 million shares of common stock outstanding.
In addition, Zonagen had cash and marketable securities of $22.9 million
(unaudited) and current liabilities of $635,000 (unaudited) at December 31,
2003, which is exclusive of any shares purchased through the tender offer
discussed above.

         The determination of the actual number of and specific shares to be
purchased and the proration amount are preliminary and subject to verification
and final confirmation by Computershare Trust Company (the depository for the
tender offer) and the proper delivery of all shares tendered and not properly
withdrawn (including shares tendered pursuant to guaranteed delivery
procedures). The final results of the tender offer will be announced promptly
following completion of the verification process and the depository will issue
payment for the shares accepted under the tender offer and return all shares not
accepted. Any questions regarding the tender offer may be directed to
Computershare Trust Company at (303) 262-0600, ext. 4732.

         The Company would like to remind its stockholders of its adjourned
annual meeting of stockholders to be held on Wednesday, January 14, 2004 at 1
p.m. at the La Quinta Inn, 28673 I-45 North, The Woodlands, Texas.

         ABOUT ZONAGEN

         Zonagen is engaged in the development of pharmaceutical products that
address diseases and conditions associated with the human reproductive system.

         THIS PRESS RELEASE CONTAINS FORWARD-LOOKING STATEMENTS CONCERNING
ZONAGEN'S TENDER OFFER. FACTORS THAT MAY AFFECT FUTURE RESULTS INCLUDE
VERIFICATION AND FINAL CONFIRMATION BY THE DEPOSITORY OF THE RESULTS OF THE
TENDER OFFER, FUTURE GENERAL AND SECTOR ECONOMIC AND MARKET CONDITIONS, THE
IMPACT OF GOVERNMENT REGULATION OF TENDER OFFERS AND DECISIONS OF THE BOARD OF
DIRECTORS. PLEASE REVIEW REPORTS FILED BY ZONAGEN, INCLUDING THE FORTHCOMING
OFFER TO PURCHASE WHICH WILL BE FILED WITH THE SECURITIES AND EXCHANGE
COMMISSION, FOR ADDITIONAL INFORMATION CONCERNING FACTORS THAT COULD AFFECT
ZONAGEN'S BUSINESS.