Supplement to Prospectus Dated May 19, 1997

                                                           Dated: April 16, 2001
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                        3,450,000 shares of Common Stock
           (Issuable upon the exercise of Class B Redeemable Warrants)

                          BENTLEY PHARMACEUTICALS, INC.

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          Bentley Pharmaceuticals, Inc. (the "Company") has extended the term of
each of the Company's Class B Redeemable Warrants (the "Class B Warrants") by an
additional 504 days. The Warrant  Expiration  Date shall now mean 5:00 P.M. (New
York time) on December 31, 2002,  extended from the original  expiration date of
February 14, 2001 and the interim expiration date of August 14, 2001. Each Class
B Warrant  may be  exercised  by the holder  thereof at any time  before the new
Warrant  Expiration Date, upon the terms and subject to the conditions set forth
in the Warrant  Agreement,  dated  February 14, 1996, by and between the Company
and American Stock Transfer & Trust Company.