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                                                                     EXHIBIT 3.1

                      RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                              BENTLEY PHARMA, INC.

     This Restated Certificate of Incorporation of BENTLEY PHARMA, INC. (the
"Corporation"), was duly adopted by the Board of Directors of the Corporation on
June 30, 1999 and the stockholders of the Corporation on June 30, 1999, as set
forth below, in accordance with Sections 228, 242 and 245 of the General
Corporation Law of the State of Delaware (the "GCL"). The original Certificate
of Incorporation was filed on May 1, 1998.

     The text of the Certificate of Incorporation as amended or supplemented
heretofore is hereby restated and further amended to read in its entirety as
follows:

                                   ARTICLE I

The name of this Corporation shall be BENTLEY PHARMACEUTICALS, INC.

                                   ARTICLE II

The address of the registered office of the Corporation in the State of Delaware
shall be at Corporation Trust Center, 1209 Orange Street, City of Wilmington,
County of New Castle, Delaware 19801. The name and address of the Corporation's
registered agent in the State of Delaware is The Corporation Trust Company, 1209
Orange Street, City of Wilmington, County of New Castle, Delaware 19801.

                                  ARTICLE III

The nature of the business and the purposes to be conducted and promoted by the
Corporation shall be to conduct any lawful business, to promote any lawful
purpose, and to engage in any lawful act or activity for which corporations may
be organized under the GCL.

                                   ARTICLE IV

The total number of shares of stock which the Corporation shall have authority
to issue is 37,000,000 shares, consisting of: (a) 35,000,000 shares of a single
class of common stock, par value $.02 per share ("Common Stock"); and (b)
2,000,000 shares of preferred stock, par value $1.00 per share ("Preferred
Stock"). The number of shares of Preferred Stock may be issued


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from time to time in one or more series as may be established from time to time
by resolution of the Board of Directors of the Corporation (the "Board of
Directors"), each of which series shall consist of such number of shares and
have such distinctive designation or title as shall be fixed by resolution of
the Board of Directors prior to the issuance of any shares of such series. The
Board of Directors is expressly authorized to provide for the issuance of all or
any shares of the Preferred Stock in one or more classes or series, and, subject
to the provisions hereof, to fix by resolution or resolutions the designations,
powers, preferences and relative, participating, optional or other special
rights, and the qualifications, limitations and restrictions, of each such class
or series.

                                   ARTICLE V

In furtherance and not in limitation of the powers conferred by statute and
subject to Article Sixth hereof, the Board of Directors is expressly authorized
to adopt, repeal, rescind, alter or amend in any respect the Bylaws of the
Corporation (the "Bylaws").

                                   ARTICLE VI

Notwithstanding Article Fifth hereof, the Bylaws may be adopted, rescinded,
altered or amended in any respect by the stockholders of the Corporation, but
only by the affirmative vote of the holders of not less than 66 2/3% of the
voting power of all outstanding shares of voting stock, regardless of class and
voting together as a single voting class, and where such action is proposed by
an interested stockholder or by any associate or affiliate of an interested
stockholder, the affirmative vote of the holders of at least a majority of the
voting power of all outstanding shares of voting stock, regardless of class and
voting together as a single voting class, other than shares held by the
interested stockholder which proposed (or the affiliate or associate of which
proposed) such action, or any affiliate or associate of such interested
stockholder; provided, however, that where such action is approved by a majority
of the continuing directors the affirmative vote of a majority of the voting
power of all outstanding shares of voting stock, regardless of class and voting
together as a single voting class, shall be required for approval of such
action.

                                  ARTICLE VII

The business and affairs of the Corporation shall be managed by and under the
direction of the Board of Directors. Except as may otherwise be provided
pursuant to Article Fourth hereof in connection with rights to elect additional
directors under specified circumstances which may be granted to the holders of
any series of Preferred Stock, the number of directors of the Corporation shall
be set in accordance with the Bylaws.


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                                  ARTICLE VIII

Each director shall serve until his successor is elected and qualified or until
his death, resignation or removal; no decrease in the authorized number of
directors shall shorten the term of any incumbent director; and additional
directors, elected pursuant to Article Fourth hereof in connection with rights
to elect such additional directors under specified circumstances which may be
granted to the holders of any series of Preferred Stock, shall not be included
in any class, but shall serve for such term or terms and pursuant to such other
provisions as are specified in the resolution of the Board of Directors
establishing such series.

                                   ARTICLE IX

     (a)  Except as may otherwise be provided pursuant to Article Fourth hereof
          in connection with rights to elect additional directors under
          specified circumstances which may be granted to the holders of any
          series of Preferred Stock, newly created directorships resulting from
          any increase in the number of directors, or any vacancies on the Board
          of Directors resulting from death, resignation, removal or other
          causes, shall be filled solely by the affirmative vote of a majority
          of the remaining directors then in office, even though less than a
          quorum of the Board of Directors.

     (b)  Any director elected in accordance with the preceding paragraph (a)
          shall hold office until the next annual meeting of stockholders or
          until such director's death, resignation or removal, whichever first
          occurs.

                                   ARTICLE X

Except for such additional directors as may be elected by the holders of any
series of Preferred Stock pursuant to the terms thereof established by a
resolution of the Board of Directors pursuant to Article Fourth hereof, any
director may only be removed from office for cause at a meeting of the
stockholders held for such purposes, and only by the affirmative vote of the
holders of not less than 66 2/3% of the voting power of all outstanding shares
of voting stock entitled to vote in connection with the election of such
director, regardless of class and voting together as a single voting class, and,
where such action is proposed by an interested stockholder, the affirmative vote
of the holders of a majority of the voting power of all outstanding shares of
voting stock, regardless of class and voting together as a single class, other
than shares held by the interested stockholder which proposed (or an affiliate
or associate which proposed) such action, or any affiliate or associate of such
interested stockholder; provided, however, that where such removal is approved
by at least a majority of the continuing directors, the affirmative vote of at
least a majority of the voting power of all outstanding shares of voting stock
entitled to vote in


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connection with the election of such director, regardless of class and voting
together as a single voting class, shall be required for approval of such
removal.

                                   ARTICLE XI

     (a)  The Board of Directors shall be divided into three (3) classes: Class
          I, Class II and Class III. The number of directors in each Class shall
          be the whole number contained in such quotient obtained by dividing
          the authorized number of directors by three (3). If a fraction is also
          contained in such quotient, then additional directors shall be
          apportioned amongst the Classes as determined by the Board of
          Directors. Each Class of directors shall be elected for a term of
          three (3) years each and the term of each Class of directors shall
          expire in subsequent years so that approximately one Class shall be
          elected annually.

     (b)  Except as provided in Article IX, paragraph (b) for directors
          appointed to newly created directorships or vacancies, each director
          shall serve for a term ending on the date of the expiration of the
          term of the Class to which the director is elected.

                                  ARTICLE XII

Meetings of stockholders of the Corporation may be held within or without the
State of Delaware, as the Bylaws may provide. The books of the Corporation may
be kept (subject to any provision of applicable law) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the Bylaws.

                                  ARTICLE XIII

          (a) In addition to any vote required by law and in addition to the
requirements of paragraph (b) of this Article XIII and except as otherwise
expressly provided in paragraph (c) of this Article XIII, the affirmative vote
of the holders of at least 66 2/3% of the outstanding shares of capital stock of
the Corporation entitled to vote thereon shall be required to authorize: (i) any
merger, combination, amalgamation or consolidation of the Corporation or any of
its subsidiaries with or into any other corporation or entity; or (ii) any sale,
lease or exchange by the Corporation of property or assets constituting all or
substantially all of the property and assets of the Corporation and its
subsidiaries taken as a whole to or with any other corporation, person or other
entity; or (iii) the dissolution or liquidation of the Corporation. Such
affirmative vote shall be required notwithstanding the fact that some lesser
percentage may be specified by law, in any contract or agreement (including any
agreement with any national securities exchange or otherwise) to which the
Corporation is a party and shall be in addition to any class or series vote to
which any class or series of stock of the Corporation may be entitled.


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          (b) In addition to the requirements of paragraph (a) of this Article
XIII and except as otherwise provided in paragraph (c) of this Article XIII, in
any transaction set forth in subparagraphs (i), (ii) or (iii) of paragraph (a)
of this Article XIII, the aggregate amount of cash and fair market value of the
consideration other than cash to be received per share by the holders of the
Corporation's Common Stock shall be at least equal to the highest of the
following amounts: (i) the fair market value per share of the Corporation's
Common Stock on the announcement date of such transaction, (ii) the fair market
value per share of the Corporation's Common Stock on the date on which the other
corporation, person or entity became an interested stockholder, or (iii) the per
share price paid by the other corporation, person or entity in the transaction
in which such other corporation, person or entity became an interested
stockholder.

          (c) The provisions of Article XIII, paragraphs (a) and (b) shall not
apply to any transaction set forth in subparagraphs (i), (ii) or (iii) of
paragraph (a) of this Article XIII if a majority of the continuing directors
shall by resolution have approved such transaction.

                                  ARTICLE XIV

For the purposes of this Restated Certificate of Incorporation, the following
definitions shall apply:

     (a)  "continuing director" means: (i) any member of the Board of Directors
          who (A) is not an interested stockholder or an affiliate or associate
          of an interested stockholder and (B) was a member of the Board of
          Directors prior to the time that an interested stockholder became an
          interested stockholder; and (ii) any person who is elected or
          nominated to succeed a continuing director, or to join the Board of
          Directors, by a majority of the continuing directors.

     (b)  The terms "affiliate," "associate," "control," "interested
          stockholder," "owner," "person" and "voting stock" shall have the
          meanings set forth in Section 203(c) of the GCL.

                                   ARTICLE XV

The provisions set forth in this Article Fifteenth and in Articles Fourth,
Fifth, Sixth, Seventh, Ninth (paragraph (a) only), Tenth, Eleventh (paragraph
(a) only), Thirteenth and Fourteenth hereof may not be repealed, rescinded,
altered or amended in any respect, and no other provision or provisions may be
adopted which impair(s) in any respect the operation or effect of any such
provision, except by the affirmative vote of the holders of not less than 66
2/3% of the voting power of all outstanding shares of voting stock, regardless
of class and voting together as a single voting class, and, where such action is
proposed by an interested stockholder or by any associate or affiliate of an
interested stockholder, the affirmative vote of the holders of a majority


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of the voting power of all outstanding shares of voting stock, regardless of
class and voting together as a single class, other than shares held by the
interested stockholder which proposed (or the affiliate or associate of which
proposed) such action, or any affiliate or associate of such interested
stockholder; provided, however, that where such action is approved by at least a
majority of the continuing directors, the affirmative vote of at least a
majority of the voting power of all outstanding shares of voting stock,
regardless of class and voting together as a single voting class, shall be
required for approval of such action.

                                  ARTICLE XVI

The Corporation reserves the right to adopt, repeal, rescind, alter or amend in
any respect any provision contained in this Certificate in the manner now or
hereafter prescribed by applicable law, and all rights conferred on stockholders
herein are granted subject to this reservation. Notwithstanding the preceding
sentence, the provisions set forth in Articles Fourth, Fifth, Sixth, Seventh,
Ninth (paragraph (a) only), Tenth, Eleventh (paragraph (a) only), Thirteenth,
Fourteenth and Fifteenth may not be repealed, rescinded, altered or amended in
any respect, and no other provision or provisions may be adopted which impair(s)
in any respect the operation or effect of any such provisions, unless such
action is approved as specified in Article Fifteenth hereof.

                                  ARTICLE XVII

No director of the Corporation shall be liable to the Corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director,
except for liability (a) for any breach of the director's duty of loyalty to the
Corporation or its stockholders, (b) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (c) under
Section 174 of the GCL, or (d) for any transaction from which the director
derived an improper personal benefit. If the GCL hereafter is amended to
authorize the further elimination or limitation of the liability of directors,
then the liability of a director of the Corporation, in addition to the
limitation on personal liability provided herein, shall be limited to the
fullest extent permitted by the amended GCL. Any repeal or modification of this
Section by the stockholders of the Corporation shall be prospective only and
shall not adversely affect any limitation on the personal liability of a
director of the Corporation existing at the time of or prior to such repeal or
modification.

                                 ARTICLE XVIII

No contract or other transaction of the Corporation with any other person, firm
or corporation, or in which this corporation is interested, shall be affected or
invalidated by: (a) the fact that any one or more of the directors or officers
of the Corporation is interested in or is a director or officer of such other
firm or corporation; or, (b) the fact that any director or officer of the


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Corporation, individually or jointly with others, may be a party to or may be
interested in any such contract or transaction, so long as the contract or
transaction is authorized, approved or ratified at a meeting of the Board of
Directors by sufficient vote thereon by directors not interested therein, to
which such fact of relationship or interest has been disclosed, or the contract
or transaction has been approved or ratified by vote or written consent of the
stockholders entitled to vote, to whom such fact of relationship or interest has
been disclosed, or so long as the contract or transaction is fair and reasonable
to the Corporation. Each person who may become a director or officer of the
Corporation is hereby relieved from any liability that might otherwise arise by
reason of his contracting with the Corporation for the benefit of himself or any
firm or corporation in which he may in any way be interested.

                                  ARTICLE XIX

The Corporation shall, to the fullest extent permitted by the GCL, as the same
may be amended and supplemented, indemnify any and all persons whom it shall
have power to indemnify from and against any and all liabilities, including,
without limitation, expenses (including attorneys' fees), judgments, fines and
amounts paid in settlement of any suit, action or proceeding to which such
person is made, or is threatened to be made, a party. The indemnification
provided for herein shall not be deemed exclusive of any other rights to which
any person may be entitled under any By-law, agreement, vote of stockholders or
disinterested directors or otherwise, both as to action in his official capacity
and as to action in another capacity while holding such office; shall continue
as to a person who has ceased to be a director, officer, employee or agent; and
shall inure to the benefit of the heirs, executors and administrators of such a
person.

     IN WITNESS WHEREOF, Bentley Pharma, Inc. has caused this Restated
Certificate of Incorporation to be executed by its President and to be attested
to by its Secretary as of the 29th day of October, 1999.

                                        BENTLEY PHARMA, INC.


                                        By: /s/ James R. Murphy
                                            ------------------------------------
                                        Name: James R. Murphy
                                        Title: President


                                        By: /s/ Michael D. Price
                                            ------------------------------------
                                        Name: Michael D. Price
                                        Title: Treasurer and Secretary


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