REGISTRATION RIGHTS AGREEMENT
                          -----------------------------


                  THIS REGISTRATION  RIGHTS AGREEMENT,  is made and entered into
as of  February  11,  1999  between  BENTLEY  PHARMACEUTICALS,  INC.,  a Florida
corporation (the "Company") and CONREX PHARMACEUTICAL  CORPORATION, a New Jersey
corporation ("Conrex").

                  WHEREAS,  upon the terms and subject to the  conditions of the
Asset  Purchase  Agreement,  dated February 1, 1999 effective as of December 31,
1998, between Conrex and Yungtai Hsu (the "Asset Purchase Agreement"),  in which
Conrex  agreed to sell  certain of its assets to Mr.  Hsu,  Conrex has agreed to
accept 359,282 shares (the "Shares") of common stock,  $0.02 par value per share
(the "Common Stock") of Bentley Pharmaceuticals, Inc. (the "Company") as part of
the Purchase Price (as defined in the Asset Purchase Agreement);

                  WHEREAS,  to induce Conrex to accept the Shares as part of the
Purchase Price,  the Company has agreed to provide certain  registration  rights
under the  Securities  Act of 1933,  as amended,  and the rules and  regulations
thereunder,  or any similar successor statute  (collectively,  the "Act"),  with
respect to the Shares;

                  WHEREAS, as of the date hereof, Conrex and the Company entered
into a  Subscription  Agreement  with  respect to the Shares (the  "Subscription
Agreement");

                  NOW,  THEREFORE,  in  consideration  of the  premises  and the
mutual covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and Conrex
hereby agree as follows:

                  1.       Definitions.

                  (a) As used in this Agreement,  the following terms shall have
the following meanings:

                  (i) "Register,"  "Registered," and  "Registration"  refer to a
registration  effected  by  preparing  and filing a  Registration  Statement  in
compliance with the Act and the declaration or ordering of effectiveness of such
Registration  Statement by the United States Securities and Exchange  Commission
(the "SEC").

                  (ii) "Registrable Securities" means the Shares.

                  (iii) "Registration  Statement" means a registration statement
of the Company under the Act,  including any amendments or  supplements  thereto
and prospectuses contained therein.

                  (iv) "Stockholder"  means Conrex and any permitted  transferee
or assignee who agrees to become bound by the  provisions  of this  Agreement in
accordance with Section 9 hereof.







                  (b)  Capitalized  terms used herein and not otherwise  defined
herein  shall  have the  respective  meanings  set forth in the  Asset  Purchase
Agreement.

                  2.       Restrictions on Transfer.

                  (a) The Stockholder acknowledges and understands that prior to
the  registration of the Shares as provided  herein,  the Shares are "restricted
securities" as defined in Rule 144 promulgated  under the Act ("Rule 144").  The
Stockholder understands that the Shares may not be offered, transferred, resold,
pledged,  hypothecated or otherwise disposed of in the absence of (i) an opinion
of Parker Chapin Flattau & Klimpl, LLP or other counsel reasonably acceptable to
the Company that such transfer may be made without registration under the Act or
(ii) an  opinion  of  Parker  Chapin  Flattau  &  Klimpl,  LLP or other  counsel
reasonably acceptable to the Company that the Shares have been Registered.

                  (b) The Stockholder  acknowledges  that the Company has issued
the Shares to the Stockholder  pursuant to an exemption from registration  under
the  Act.  Stockholder  represents  that  (i) it has  acquired  the  Shares  for
investment  and  without  any view  toward  distribution  of any of  Registrable
Securities  to any other person,  (ii) it will not sell or otherwise  dispose of
the Shares except in compliance with the registration  requirements or exemption
provisions  under the Act and (iii) before any sale or other  disposition of any
of the Shares other than in a sale registered  under the Act or pursuant to Rule
144 or 144A (or any similar  provisions then in force) under the Act (unless the
Company  shall  have been  advised  by  counsel  that the sale does not meet the
requirements  of Rule 144 or Rule 144A,  as the case may be, for such sale),  it
will  deliver  to the  Company  an opinion  of  counsel,  in form and  substance
reasonably  satisfactory to the Company, to the effect that such registration is
unnecessary.

                  (c) Each instrument or certificate  evidencing or representing
the Shares, and any certificate issued in exchange therefor or transfer thereof,
shall bear legends substantially in the following form:

                  "THE SECURITIES  REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED  UNDER THE  SECURITIES ACT OF 1933, AS AMENDED (THE
                  "ACT") OR APPLICABLE  STATE  SECURITIES  LAWS.  THE SECURITIES
                  HAVE BEEN ACQUIRED FOR INVESTMENT PURPOSES ONLY AND MAY NOT BE
                  OFFERED FOR SALE,  SOLD,  HYPOTHECATED,  ASSIGNED,  PLEDGED OR
                  OTHERWISE   TRANSFERRED   IN  THE  ABSENCE  OF  AN   EFFECTIVE
                  REGISTRATION  STATEMENT  COVERING THE SECURITIES UNDER THE ACT
                  OR APPLICABLE  STATE SECURITIES LAWS, OR AN OPINION OF COUNSEL
                  SATISFACTORY  TO THE ISSUER THAT  REGISTRATION IS NOT REQUIRED
                  UNDER THE ACT OR APPLICABLE STATE SECURITIES LAWS."

                                       -2-





                  3.  Registration.  The Company shall prepare and file with the
SEC a  Registration  Statement  on  April  1,  1999 or as  soon  as  practicable
thereafter on an appropriate  form for registering for resale by the Stockholder
the  Registrable  Securities  (or such  lesser  number as may be required by the
SEC),  and the  Company  shall use its best  efforts  to cause the  Registration
Statement  to be declared  effective  as soon as  practicable  after filing (the
"Effective  Date").  The rights under this  paragraph  may only be exercised one
time.

                  4.   Obligations  of  the  Company.   In  connection   with  a
registration of the Registrable  Securities under Section 3 hereof,  the Company
shall do each of the following:

                  (a)  Prepare and file with the SEC, a  Registration  Statement
with respect to the Registrable Securities,  and thereafter use its best efforts
to cause each Registration  Statement relating to the Registrable  Securities to
become  effective on the Effective  Date,  and keep the  Registration  Statement
effective at all times until the earliest (the "Registration Period") of (i) the
date  that is two  years  after  the  Closing  Date;  (ii)  the  date  when  the
Stockholder may sell all Registrable Securities under Rule 144 or (iii) the date
the  Stockholder  no  longer  owns  any of  the  Registrable  Securities,  which
Registration Statement shall not contain any untrue statement of a material fact
or omit to state a material fact  required to be stated  therein or necessary to
make the statements  therein,  in light of the  circumstances in which they were
made, not misleading;

                  (b) Prepare and file with the SEC such  amendments  (including
post-effective amendments) and supplements to the Registration Statement and the
prospectus  used  in  connection  with  the  Registration  Statement  as  may be
necessary to keep the Registration  Statement  effective at all times during the
Registration  Period,  and,  during the  Registration  Period,  comply  with the
provisions  of the  Act  with  respect  to the  disposition  of all  Registrable
Securities of the Company covered by the Registration  Statement until such time
as all of such  Registrable  Securities have been disposed of in accordance with
the  intended  methods of  disposition  by the seller or sellers  thereof as set
forth in the Registration Statement;

                  (c)  The  Company  shall  permit  a  single  firm  of  counsel
designated by the Stockholder to review the Registration  Statement a reasonable
period of time prior to the Company's filing of the Registration  Statement with
the SEC;

                  (d)  Furnish  to  the   Stockholder  (i)  promptly  after  the
Registration Statement is prepared and publicly distributed, filed with the SEC,
or  received  by the  Company,  one  copy of the  Registration  Statement,  each
prospectus,  and each amendment or supplement  thereto,  and (ii) such number of
copies of a prospectus,  and all  amendments  and  supplements  thereto and such
other  documents,  as  the  Stockholder  may  reasonably  request  in  order  to
facilitate  the  disposition  of  the  Registrable   Securities   owned  by  the
Stockholder;

                  (e) As promptly as  practicable  after  becoming aware of such
event,  the Company shall notify the  Stockholder of (i) the issuance by the SEC
of a stop order suspending the effectiveness of the Registration Statement, (ii)
the  happening  of any event of which the Company has  knowledge  as a result of
which the prospectus included in the Registration Statement, as then in

                                       -3-





effect,  includes  an untrue  statement  of a material  fact or omits to state a
material fact required to be stated  therein or necessary to make the statements
therein,  in  light  of the  circumstances  under  which  they  were  made,  not
misleading,  or (iii) the  occurrence  or  existence  of any  pending  corporate
development  that,  in the  reasonable  discretion  of  the  Company,  makes  it
appropriate to suspend the availability of the Registration  Statement,  and use
its  best  efforts  promptly  to  prepare  a  supplement  or  amendment  to  the
Registration Statement to correct such untrue statement or omission, and deliver
such number of copies of such  supplement or amendment to the  Stockholder as it
may reasonably request; provided that, for not more than twenty days (or a total
of not more than forty days in any twelve  month  period,  the Company may delay
the  disclosure of material  non-public  information  concerning the Company (as
well as prospectus or Registration  Statement  updating) the disclosure of which
at the time is not,  in the  good  faith  opinion  of the  Company,  in the best
interests  of the  Company  and in the  opinion of counsel  to the  Company  (an
"Allowed Delay"); provided,  further, that the Company shall promptly (i) notify
the Stockholder in writing of the existence of material  non-public  information
giving rise to an Allowed  Delay and (ii) advise the  Stockholder  in writing to
cease all sales under the  Registration  Statement  until the end of the Allowed
Delay. Upon expiration of the Allowed Delay, the Company shall again be bound by
the first sentence of this Section 4(e) with respect to the  information  giving
rise thereto;

                  (f) As promptly as  practicable  after  becoming aware of such
event,  notify the Stockholder who holds Registrable  Securities being sold (or,
in the event of an  underwritten  offering,  the managing  underwriters)  of the
issuance  by  the  SEC  of  any  notice  declaring  the   effectiveness  of  the
Registration   Statement  or  any  stop  order  or  other   suspension   of  the
effectiveness of the Registration Statement at the earliest possible time; and

                  (g) Take all other  reasonable  actions  necessary to expedite
and facilitate  disposition by the  Stockholder  of the  Registrable  Securities
pursuant to the Registration Statement.

                  5.  Obligations  of the  Stockholder.  In connection  with the
registration  of the  Registrable  Securities,  the  Stockholder  shall have the
following obligations:

                  (a) It shall be a condition  precedent to the  obligations  of
the Company to complete the registration pursuant to this Agreement with respect
to the  Registrable  Securities of the Stockholder  that the  Stockholder  shall
furnish to the  Company  such  information  regarding  itself,  the  Registrable
Securities held by it, and the intended method of disposition of the Registrable
Securities  held  by  it,  as  shall  be  reasonably   required  to  effect  the
registration of such Registrable  Securities and shall execute such documents in
connection  with such  registration  as the Company may reasonably  request.  At
least five days prior to the first  anticipated  filing date of the Registration
Statement,  the Company  shall notify the  Stockholder  of the  information  the
Company  requires from the  Stockholder  (the  "Requested  Information")  if the
Stockholder  elects  to have  any of the  Stockholder's  Registrable  Securities
included in the  Registration  Statement.  If at least three  Business  Days (as
defined  below)  prior to the  filing  date the  Company  has not  received  the
Requested  Information  from  the  Stockholder,  then the  Company  may file the
Registration   Statement  without  including   Registrable   Securities  of  the
Stockholder;

                                       -4-





                  (b)  The   Stockholder   by  acceptance  of  the   Registrable
Securities  agrees to cooperate with the Company as reasonably  requested by the
Company  in  connection  with the  preparation  and  filing of the  Registration
Statement hereunder,  unless the Stockholder has notified the Company in writing
of the Stockholder's  election to exclude all of its Registrable Securities from
the Registration Statement; and

                  (c) The  Stockholder  agrees that,  upon receipt of any notice
from the Company of the happening of any event of the kind  described in Section
4(e) or 4(f), above, the Stockholder will immediately discontinue disposition of
Registrable  Securities  pursuant to the  Registration  Statement  covering such
Registrable  Securities  until the  Stockholder's  receipt  of the copies of the
supplemented or amended prospectus  contemplated by Section 4(e) or 4(f) and, if
so directed by the Company, the Stockholder shall deliver to the Company (at the
expense of the Company) or destroy (and deliver to the Company a certificate  of
destruction)  all  copies in the  Stockholder's  possession,  of the  prospectus
covering  such  Registrable  Securities  current  at the time of receipt of such
notice.

                  6.       Expenses of Registration.

                  (a)  All  reasonable  expenses,  other  than as set  forth  in
Section  6(b)  hereof,  filings  or  qualifications  pursuant  to Section 4, but
including,  without limitation,  all registration,  listing,  and qualifications
fees,  printers and accounting  fees, the fees and  disbursements of counsel for
the Company, shall be borne by the Company.

                  (b) All  underwriting  discounts and  commissions  incurred in
connection with registrations shall be paid by the Stockholder.

                  7.  Indemnification.  Conrex shall indemnify and hold harmless
the Company and each officer, director or control person of any such entity, who
is or may be a  party  or is or may be  threatened  to be  made a  party  to any
threatened,  pending or completed  action,  suit or  proceeding,  whether civil,
criminal,  administrative or investigative, by reason of or arising from (i) any
actual or alleged  misrepresentation  or  misstatement  of facts or  omission to
represent  or state  facts  made or  alleged  to have been made by Conrex to the
Company, (or its agents or representatives),  or omitted or alleged to have been
omitted  by  Conrex,  concerning  Conrex,  or  Conrex's  authority  to invest or
financial position in connection with the offering or sale of the Shares in this
Agreement,  in the  Subscription  Agreement or elsewhere,  or (ii) any breach of
warranty or failure to comply with any covenant  contained in this  Agreement or
in  the  Subscription  Agreement,   including,   without  limitation,  any  such
misrepresentation,  misstatement  or  omission,  or  breach of any  warranty  or
covenant,  contained herein or any other document  submitted by Conrex,  against
losses,  liabilities  and  expenses  for which  the  Company,  or its  officers,
directors  or control  persons  has not  otherwise  been  reimbursed  (including
attorneys'  fees,  judgments,  fines and amounts paid in  settlement  in matters
settled in accordance with the provision of the following paragraph) incurred by
the Company, or such officer, director or control person in connection with such
action, suit or proceeding; provided, however, that Conrex will not be liable in
any such case for losses, claims, damages,  liabilities or expenses that a court
of competent jurisdiction shall have found in a final judgment to have arisen

                                       -5-





primarily from the gross negligence or willful  misconduct of the Company or the
party claiming a right to indemnification.

                  In case any  proceeding  shall  be  instituted  involving  any
person  with  respect  to  whom  indemnity  may  be  sought,  such  person  (the
"Indemnified  Party") shall promptly notify Conrex, and Conrex, upon the request
of the Indemnified Party,  shall retain counsel  reasonably  satisfactory to the
Indemnified  Party to represent the Indemnified  Party and any others Conrex may
designate in such proceedings and shall pay as incurred the fees and expenses of
such counsel related to such proceeding. In any such proceeding, any Indemnified
Party shall have the right to retain its own counsel at its own expense,  except
that Conrex shall pay as incurred  the fees and expenses of counsel  retained by
the  Indemnified  Party in the event that (i) Conrex and the  Indemnified  Party
shall have  mutually  agreed to the retention of such counsel or, (ii) the named
parties to any such proceeding  (including any impleaded  parties)  include both
Conrex and the Indemnified Party and  representation of both parties by the same
counsel would be  inappropriate,  in the reasonable  opinion of the  Indemnified
Party, due to actual or potential differing interests between them. Conrex shall
not be liable for any settlement of any proceeding  effected without its written
consent,  but if settled with such  consent or if there be a final  judgment for
the plaintiff,  Conrex agrees to indemnify the  Indemnified  Party to the extent
set forth in this Agreement.

                  In the event a claim for  indemnification  as described herein
is determined to be  unenforceable  by a final  judgment of a court of competent
jurisdiction,  then Conrex shall  contribute  to the aggregate  losses,  claims,
damages or liabilities to which the Company or its officers,  directors, agents,
employees or controlling persons may be subject in such amount as is appropriate
to reflect the relative  benefits  received by each of the  undersigned  and the
party seeking contribution on the one hand and the relative faults of Conrex and
the party seeking  contribution on the other, as well as any relevant  equitable
considerations.

                  The provisions of this Agreement  relating to  indemnification
and  contribution  shall  survive  termination  of this  Agreement  and shall be
binding upon any successors or assigns of Conrex.

                  8.  Termination  of  Registration  Rights.  The rights granted
pursuant  to this  Agreement  shall  terminate  as to the  Stockholder  upon the
occurrence of any of the following:

                  (a) all of the Registrable Securities have been registered; or

                  (b) all of the Registrable Securities may be sold without such
registration pursuant to Rule 144.

                  9.       Miscellaneous.

                  (a) A person or entity is deemed to be a holder of Registrable
Securities  whenever  such  person or entity  owns of  record  such  Registrable
Securities.  If  the  Company  receives  conflicting  instructions,  notices  or
elections from two or more persons or entities with respect to the same

                                       -6-





Registrable  Securities,  the Company shall act upon the basis of  instructions,
notice  or  election  received  from the  registered  owner of such  Registrable
Securities.

                  (b) Notices.  All notices,  demands or other communications to
be given or delivered  under or by reason of the  provisions  of this  Agreement
shall be in writing  and shall be deemed to have been  given (a) when  delivered
personally to the recipient, (b) when sent to the recipient by telecopy (receipt
electronically confirmed by sender's telecopy machine) if during normal business
hours of the recipient, otherwise on the next Business Day ("Business Day" means
a day other than Saturday, Sunday or any day on which banks located in the State
of New York are  authorized  or obligated to close),  (c) one Business Day after
the date  when  sent to the  recipient  by  reputable  express  courier  service
(charges  prepaid) or (d) seven  Business Days after the date when mailed to the
recipient by certified or registered mail,  return receipt requested and postage
prepaid.  Such notices,  demands and other communications will be sent to Conrex
and to the Company at the addresses indicated below.

                  If to Conrex, to:

                           Conrex Pharmaceutical Corporation
                           5127 West Chester Pike
                           Newtown Square, Pennsylvania 19073
                           Attention:  Phyllis Hsieh
                           Facsimile No.: (610) 355-2453

                  with a copy to:

                           Synnestvedt & Lechner LLP
                           Suite 2600 Aramark Tower
                           1101 Market Street
                           Philadelphia, PA 19107
                           Attention: John T. Synnestvedt
                           Facsimile No.: (215) 923-2189

                  If to the Company, to:

                           Bentley Pharmaceuticals, Inc.
                           Two Urban Centre, Suite 400
                           4890 West Kennedy Blvd.
                           Tampa, Florida 33609
                           Attention:  James R. Murphy
                           Facsimile No.:  (813) 282-8941

                                       -7-





                  With a copy to:

                           Parker Chapin Flattau & Klimpl, LLP
                           1211 Avenue of the Americas
                           New York, New York 10036
                           Attention:  Mark S. Hirsch
                                       Jordan A. Horvath
                           Facsimile:  (212) 704-6288


                  (c) Assignment; Benefit. This Agreement may not be assigned by
Conrex  without the prior  written  consent of the  Company  and any  assignment
without  such consent  shall be void.  The rights  under this  Agreement  may be
assigned by Conrex to its  Stockholders if Conrex  distributes the Shares to its
Stockholders  as a dividend  to the extent  the Shares are  distributed  to each
Stockholder, provided that such Stockholders agree to be bound by all provisions
of this Agreement and all such  transfers are in accordance  with all applicable
laws. Upon such  assignment  Conrex and its  Stockholders  will have the various
rights under this  Agreement  which  pertain to the Shares then owned by each of
them.  This  Agreement  may be  assigned  by the Company to any person or entity
which purchases all or  substantially  all of the stock or assets of the Company
or is the successor to the Company by merger or  consolidation.  This  Agreement
shall be binding upon and inure to the benefit of the respective  successors and
permitted assigns of the Company and of Conrex.

                  (d) Severability.  The invalidity or  unenforceability  of any
provisions of this Agreement shall not affect the validity or  enforceability of
any other provision of this Agreement,  each of which shall remain in full force
and effect.

                  (e) Amendments. This Agreement may be amended, supplemented or
modified,  and any  provision  hereof may be waived,  only pursuant to a written
instrument  making  specific  reference to this Agreement  signed by each of the
parties hereto.

                  (f) Counterparts. This Agreement may be executed in any number
of  counterparts,  each of which shall be deemed an  original,  but all of which
together shall constitute one and the same instrument.

                  (g)  Governing  Law. This  Agreement  shall be governed by and
construed in accordance  with the laws of the State of New York  applicable to a
contract  executed and  performed  in such State  without  giving  effect to the
conflicts  of laws  principles  thereof,  except that if it is  necessary in any
other  jurisdiction  to have  the law of such  other  jurisdiction  govern  this
Agreement in order for this  Agreement to be effective in any respect,  then the
laws of such other jurisdiction shall govern this Agreement to such extent.

                                       -8-





                  (h)      Arbitration of Disputes

                                    (i) If any  controversy  or  dispute  arises
under, out of or in relation to any of the provisions  hereof,  such controversy
or dispute shall be submitted  for  arbitration  in New York,  New York before a
panel of  three  arbitrators,  one of  which  shall  be  selected  by the  party
initiating such  arbitration,  one of which shall be selected by the other party
and the third of which (the  "Third  Arbitrator")  shall be  selected by the two
arbitrators so selected;  provided,  however,  that in the event that such other
arbitrators shall not agree on the selection of the Third Arbitrator,  the Third
Arbitrator shall be selected by the American Arbitration  Association located in
New York,  New York.  Any dispute or  controversy  submitted to  arbitration  in
accordance  with the  provisions  of this Section  shall be  determined  by such
arbitrators in accordance with the Commercial  Arbitration Rules of the American
Arbitration Association then existing.

                                    (ii) The  arbitrators  may award any  relief
which they shall deem proper in the circumstances,  without regard to the relief
which  would  otherwise  be  available  to any party in a court of law or equity
including,  without limitation, an award of money damages, specific performance,
injunctive  relief and/or  declaratory  relief,  however,  such an award may not
include  punitive  damages.  The award and findings of the arbitrators  shall be
conclusive  and  binding  upon all of the  parties  hereto,  whether  or not all
parties hereto participate in the arbitration proceeding,  and judgment upon the
award may be entered in any court of competent jurisdiction upon the application
of  any  party.   The  parties  hereby  agree  that  such  courts  of  competent
jurisdiction  shall  include,  but not be limited to, the courts  located in any
jurisdiction  in which the party  against whom such  judgment is being  enforced
maintains any assets.

                                    (iii) The costs of the  arbitration and each
party's associated costs shall be borne by the losing party. Notwithstanding the
foregoing, if the parties reach a compromise, the costs of the arbitration shall
be borne  equally by the parties  and each party  shall bear its own  associated
costs.

                                    (iv)  Notwithstanding  the  foregoing,   the
parties reserve the right to seek and obtain injunctive  relief,  whether in the
form of a temporary  restraining order,  preliminary  injunction,  injunction to
enforce an arbitration award, or other order of similar import, from the federal
and state  courts  located  in New York,  New York  prior to,  during,  or after
commencement or prosecution or arbitration proceedings of the final decision and
award of the arbitrators;  provided,  however, that such preliminary  injunctive
relief shall be subject to final arbitral decisions.

                                    (v) Each party  hereby  consents  and agrees
that the federal and state courts  located in New York, New York each shall have
exclusive personal jurisdiction and proper venue with respect to any such action
seeking  injunctive  or similar  relief  hereunder.  In any dispute  between the
parties,  neither party will raise, and each party hereby expressly waives,  any
objection  or  defense to any such court as an  inconvenient  forum.  Each party
hereby waives personal service of any summons, complaint or other process, which
may be delivered by any of the means  permitted  for notices under Section 10(b)
hereof

                                       -9-




                  IN WITNESS  WHEREOF,  the parties have  executed and delivered
this Agreement as of the day and year first written above.

                                         BENTLEY PHARMACEUTICALS, INC.


                                         By:  /s/ James R. Murphy
                                             -----------------------------------
                                            James R. Murphy, Chairman, President
                                               and Chief Executive Officer

                                         CONREX PHARMACEUTICAL CORPORATION


                                         By:  /s/  Phyllis Hsieh
                                              ----------------------------------
                                                 Phyllis Hsieh, President



                                      -10-