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                              AMENDED AND RESTATED

                                     BY-LAWS
                                       OF

                             BARR LABORATORIES, INC.

                                      AS OF
                                 AUGUST 11, 1999

                              ARTICLE I - OFFICES
                              -------------------

The office of the Corporation shall be located in the Village of Pomona, County
of Rockland, and State of New York. The Corporation may also maintain offices at
such other places within or without the United States as the Board of Directors
may, from time to time, determine.

                      ARTICLE II - MEETING OF SHAREHOLDERS
                      ------------------------------------

SECTION 1 - ANNUAL MEETINGS:
----------------------------

An annual meeting of shareholders shall be held each year for the election of
directors at such date, time and place either within or without the State of New
York as shall be designated by the Board of Directors. Any other proper business
may be transacted at the annual meeting of shareholders.

SECTION 2 - SPECIAL MEETINGS:
-----------------------------

Special meetings of the shareholders may be called at any time by the Board of
Directors, and shall be called by the President or the Secretary at the written
request of the holders of twenty-five per cent (25%) of the shares then
outstanding and entitled to vote thereat, or as otherwise required under the
provisions of the Business Corporation Law.

SECTION 3 - PLACE OF MEETINGS:
------------------------------

All meetings of shareholders shall be held at the principal office of the
Corporation, or at such other places within or without the State of New York as
shall be designated in the notices or waivers of notice of such meetings.

SECTION 4 - NOTICE OF MEETINGS:
-------------------------------

(a)   Written notice of each meeting of shareholders, whether annual or special,
      stating the time when and place where it is to be held, shall be served
      either personally or by mail, not less than ten or more than sixty days
      before the meeting, upon each
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      shareholder of record entitled to vote at such meeting, and to any other
      shareholder to whom the giving of notice may be required by law. Notice of
      a special meeting shall also state the purpose or purposes for which the
      meeting is called, and shall indicate that it is being issued by, or at
      the direction of, the person or persons calling the meeting. If, at any
      meeting, action is proposed to be taken that would, if taken, entitle
      shareholders to receive payment for their shares pursuant to the Business
      Corporation Law, the notice of such meeting shall include a statement of
      that purpose and to that effect. If mailed, such notice shall be directed
      to each such shareholder at his address, as it appears on the records of
      the shareholders of the Corporation, unless he shall have previously filed
      with the Secretary of the Corporation a written request that notices
      intended for him be mailed to some other address, in which case, it shall
      be mailed to the address designated in such request.

(b)   Notice of any meeting need not be given to any shareholder who attends
      such meeting, in person or by proxy, or to any shareholder who, in person
      or by proxy, submits a signed waiver of notice either before or after such
      meeting. Notice of any adjourned meeting of shareholders need not be
      given, unless otherwise required by statute.

SECTION 5 - QUORUM:
-------------------

(a)   Except as otherwise provided herein, or by statute, or in the Certificate
      of Incorporation (such Certificate and any amendments thereof being
      hereinafter collectively referred to as the "Certificate of
      Incorporation"), at all meetings of shareholders of the Corporation, the
      presence at the commencement of such meetings in person or by proxy of
      shareholders holding of record a majority of the total number of shares of
      the Corporation then issued and outstanding and entitled to vote, shall be
      necessary and sufficient to constitute a quorum for the transaction of any
      business. The withdrawal of any shareholder after the commencement of a
      meeting shall have no effect on the existence of a quorum, after a quorum
      has been established at such meeting.

(b)   Despite the absence of a quorum at any annual or special meeting of
      shareholders, the shareholders, by a majority of the votes cast by the
      holders of shares entitled to vote thereon, may adjourn the meeting. At
      any such adjourned meeting at which a quorum is present, any business may
      be transacted which might have been transacted at the meeting as
      originally called if a quorum had been present.

SECTION 6 - VOTING:
-------------------

(a)   Except as otherwise provided by statute or by the Certificate of
      Incorporation, any corporate action, other than the election of directors,
      to be taken by vote of the shareholders, shall be authorized by a majority
      of votes cast at a meeting of shareholders by the holders of shares
      entitled to vote thereon.


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(b)   Except as otherwise provided by statute or by the Certificate of
      Incorporation, at each meeting of shareholders, each holder of record of
      stock of the Corporation entitled to vote thereat, shall be entitled to
      one vote for each share of stock registered in his name on the books of
      the Corporation.

(c)   Each shareholder entitled to vote or to express consent or dissent without
      a meeting may authorize another person or persons to act for him by proxy
      by any valid means set forth in the Business Corporation Law. No proxy
      shall be valid after the expiration of eleven months from the date of its
      execution, unless the person executing it shall have specified therein the
      length of time it is to continue in force. Such instrument shall be
      exhibited to the Secretary at the meeting.

(d)   Any resolution in writing, signed by all of the shareholders entitled to
      vote thereon, shall be and constitute action by such shareholders to the
      effect therein expressed, with the same force and effect as if the same
      had been duly passed by unanimous vote at a duly called meeting of
      shareholders.

                        ARTICLE III - BOARD OF DIRECTORS
                        --------------------------------

SECTION 1 - NUMBER, ELECTION AND TERM OF OFFICE:
------------------------------------------------

(a)   The number of the directors of the Corporation shall be eight (8), unless
      and until otherwise determined by vote of a majority of the entire Board
      of Directors. The number of Directors shall not be less than three, unless
      all of the outstanding shares are owned beneficially and of record by less
      than three shareholders, in which event the number of directors shall not
      be less than the number of shareholders.

(b)   Except as may otherwise be provided herein or in the Certificate of
      Incorporation, the members of the Board of Directors of the Corporation,
      who need not be shareholders, shall be elected by a plurality of the votes
      cast at a meeting of shareholders, by the holders of shares entitled to
      vote in the election.

(c)   Each director shall hold office until the annual meeting of the
      shareholders next succeeding his election, and until his successor is
      elected and qualified, or until his prior death, resignation or removal.

SECTION 2 - DUTIES AND POWERS:
------------------------------

The Board of Directors shall be responsible for the control and management of
the affairs, property and interests of the Corporation, and may exercise all
powers of the Corporation, except as are in the Certificate of Incorporation or
by statute expressly conferred upon or reserved to the shareholders.

SECTION 3 - ANNUAL AND REGULAR MEETINGS; NOTICE:
------------------------------------------------

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(a)   A regular annual meeting of the Board of Directors shall be held
      immediately following the annual meeting of the shareholders, at the place
      of such annual meeting of shareholders.

(b)   The Board of Directors, from time to time, may provide by resolution for
      the holding of other regular meetings of the Board of Directors, and may
      fix the time and place thereof.

(c)   Notice of any regular meeting of the Board of Directors shall not be
      required to be given and, if given, need not specify the purpose of the
      meeting; provided, however, that in case the Board of Directors shall fix
      or change the time or place of any regular meeting, notice of such action
      shall be given to each director who shall not have been present at the
      meeting at which such action was taken within the time limited, and in the
      manner set forth in paragraph (b) of Section 4 of this Article III, with
      respect to special meetings, unless such notice shall be waived in the
      manner set forth in paragraph (c) of such Section 4.

SECTION 4 - SPECIAL MEETINGS; NOTICE:
-------------------------------------

(a)   Special meetings of the Board of Directors shall be held whenever called
      by one of the directors, at such time and place as may be specified in the
      respective notices or waivers of notice thereof.

(b)   Notice of special meetings shall be mailed directly to each director,
      addressed to him at his residence or usual place of business, at least two
      (2) days before the day on which the meeting is to be held, or shall be
      sent to him at such place by telegram, radio or cable, or shall be
      delivered to him personally or given to him orally, not later than the day
      before the day on which the meeting is to be held. A notice, or waiver of
      notice, except as required by Section 8 of this Article III, need not
      specify the purpose of the meeting.

(c)  Notice of any special meeting shall not be required to be given to any
     director who shall attend such meeting without protesting prior thereto or
     at its commencement, the lack of notice to him, or who submits a signed
     waiver of notice, whether before or after the meeting.

SECTION 5 - CHAIRMAN:
---------------------

At all meetings of the Board of Directors, the Chairman of the Board, if any and
if present, shall preside. If there shall be no Chairman, or he shall be absent,
then the President shall preside, and in his absence, a Chairman chosen by the
directors shall preside.

SECTION 6 - QUORUM AND ADJOURNMENTS:
------------------------------------

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(a)  At all meetings of the Board of Directors, the presence of a majority of
     the entire Board shall be necessary and sufficient to constitute a quorum
     for the transaction of business, except as otherwise provided by law, by
     the Certificate of Incorporation, or by these By-Laws.

(b)  A majority of the directors present at the time and place of any regular or
     special meeting, although less than a quorum, may adjourn the same from
     time to time without notice.

SECTION 7 - MANNER OF ACTING:
-----------------------------

(a)  At all meetings of the Board of Directors, each director present shall have
     one vote, irrespective of the number of shares of stock, if any, which he
     may hold.

(b)  Except as otherwise provided by statute, by the Certificate of
     Incorporation, or by these By-Laws, the action of a majority of the
     directors present at any meeting at which a quorum is present shall be the
     act of the Board of Directors.

SECTION 8 - VACANCIES:
----------------------

Any vacancy in the Board of Directors occurring by reason of an increase in the
number of directors, or by reason of the death, resignation, disqualification,
removal (unless a vacancy created by the removal of a director by the
shareholders shall be filled by the shareholders at the meeting at which the
removal was effected) or inability to act of any director, or otherwise, shall
be filled for the unexpired portion of the term by a majority vote of the
remaining directors, though less than a quorum at any regular meeting or special
meeting of the Board of Directors called for that purpose.

SECTION 9 - RESIGNATION:
------------------------

Any director may resign at any time by giving written notice to the Board of
Directors, the President or the Secretary of the Corporation. Unless otherwise
specified in such written notice, such resignation shall take effect upon
receipt thereof by the Board of Directors or such officer, and the acceptance of
such resignation shall not be necessary to make it effective.

SECTION 10 - REMOVAL:
---------------------

Any director may be removed with or without cause at any time by the
shareholders, at a special meeting of the shareholders called for that purpose,
and may be removed for cause by action of the Board.

SECTION 11 - COMPENSATION:
--------------------------

Unless otherwise provided by the Certificate of Incorporation, the Board of
Directors


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shall have the authority to fix the compensation of directors, which
compensation may include the reimbursement of expenses incurred in connection
with meetings of the Board of Directors or a committee thereof; provided,
however, that nothing herein contained shall be construed to preclude any
director from serving the Corporation in any other capacity and receiving
compensation therefor.

SECTION 12 - COMMITTEE:
-----------------------

The Board of Directors, by resolution adopted by a majority of the entire Board,
may from time to time designate from among its members an executive committee
and such other committees, and alternate members thereof, as they may deem
desirable, each consisting of one or more members, with such powers and
authority (to the extent permitted by law) as may be provided in such
resolution. Each such committee shall serve at the pleasure of the Board.

                              ARTICLE IV - OFFICERS
                              ---------------------

SECTION 1 - NUMBER, QUALIFICATIONS, ELECTION AND TERM OF OFFICE:
----------------------------------------------------------------

(a)  The officers of the Corporation shall consist of a President, a Secretary,
     a Treasurer, and such other officers, including a Chairman of the Board of
     Directors, and one or more Vice Presidents, as the Board of Directors may
     from time to time deem advisable. Any officer other than the Chairman of
     the Board of Directors may be, but is not required to be, a director of the
     Corporation. Any two or more offices may be held by the same person.

(b)  The officers of the Corporation shall be elected by the Board of Directors
     at the regular annual meeting of the Board following the annual meeting of
     shareholders.

(c)  Each officer shall hold office until the annual meeting of the Board of
     Directors next succeeding his election, and until his successor shall have
     been elected and qualified, or until his death, resignation or removal.

SECTION 2 - RESIGNATION:
------------------------

Any officer may resign at any time by giving written notice of such resignation
to the Board of Directors, or to the President or the Secretary of the
Corporation. Unless otherwise specified in such written notice, such resignation
shall take effect upon receipt thereof by the Board of Directors or by such
officer, and the acceptance of such resignation shall not be necessary to make
it effective.

SECTION 3 - REMOVAL:
--------------------

Any officer may be removed, either with or without cause, and a successor
elected by the Board at any time.

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SECTION 4 - VACANCIES:
----------------------

A vacancy in any office by reason of death, resignation, inability to act,
disqualification, or any other cause, may at any time be filled for the
unexpired portion of the term by the Board of Directors.

SECTION 5 - DUTIES OF OFFICERS:
-------------------------------

Officers of the Corporation shall, unless otherwise provided by the Board of
Directors, each have such powers and duties as generally pertain to their
respective offices as well as such powers and duties as may be set forth in
these By-Laws, or may from time to time be specifically conferred or imposed by
the Board of Directors.

SECTION 6 - SURETIES AND BONDS:
-------------------------------

In case the Board of Directors shall so require, any officer, employee or agent
of the Corporation shall execute to the Corporation a bond in such sum, and with
such surety or sureties as the Board of Directors may direct, conditioned upon
the faithful performance of his duties to the Corporation, including
responsibility for negligence and for the accounting for all property, funds or
securities of the Corporation which may come into his hands.

SECTION 7 - SHARES OF OTHER CORPORATIONS:
-----------------------------------------

Whenever the Corporation is the holder of shares of any other corporation, any
right or power of the Corporation as such shareholder (including the attendance,
acting and voting at shareholders meetings and execution of waivers, consents,
proxies or other instruments) may be exercised on behalf of the Corporation by
the President, any Vice President, or such other person as the Board of
Directors may authorize.

                           ARTICLE V - SHARES OF STOCK
                           ---------------------------

SECTION 1 - CERTIFICATE OF STOCK:
---------------------------------

(a)  The certificates representing shares of the Corporation shall be in such
     form as shall be adopted by the Board of Directors, and shall be numbered
     and registered in the order issued. They shall bear the holder's name and
     the number of shares, and shall be signed by (i) the Chairman of the Board
     or the President or a Vice President, and (ii) the Secretary or Treasurer,
     or any Assistant Secretary or Assistant Treasurer, and may bear the
     corporate seal.

(b)  No certificate representing shares shall be issued until the full amount of
     consideration therefor has been paid, except as otherwise permitted by law.

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(c)   The Board of Directors may authorize the issuance of certificates for
      fractions of a share which shall entitle the holder to exercise voting
      rights, receive dividends and participate in liquidating distributions, in
      proportion to the fractional holdings, or it may authorize the payment in
      cash of the fair value of fractions of a share as of the time when those
      entitled to receive such fractions are determined; or it may authorize the
      issuance, subject to such conditions as may be permitted by law, of scrip
      in registered or bearer form over the signature of an officer or agent of
      the Corporation, exchangeable as therein provided for full shares, but
      such scrip shall not entitle the holder to any rights of a shareholder,
      except as therein provided.

SECTION 2 - LOST OR DESTROYED CERTIFICATES:
-------------------------------------------

The holder of any certificate representing shares of the Corporation shall
immediately notify the Corporation of any loss or destruction of the certificate
representing the same. The Corporation may issue a new certificate in the place
of any certificate theretofore issued by it, alleged to have been lost or
destroyed. On production of such evidence of loss or destruction as the Board of
Directors in its discretion may require, the Board of Directors may, in its
discretion, require the owner of the lost or destroyed certificate, or his legal
representatives, to give the Corporation a bond in such sum as the Board may
direct, and with such surety or sureties as may be satisfactory to the Board, to
indemnify the Corporation against any claims, loss, liability or damage it may
suffer on account of the issuance of the new certificate. A new certificate may
be issued without requiring any such evidence or bond when, in the judgment of
the Board of Directors, it is proper so to do.

SECTION 3 - TRANSFERS OF SHARES:
--------------------------------

(a)   Transfers of shares of the Corporation shall be made on the share records
      of the Corporation only by the holder of record thereof, in person or by
      his duly authorized attorney, upon surrender for cancellation of the
      certificate or certificates representing such shares, with an assignment
      or power of transfer endorsed thereon or delivered therewith, duly
      executed, with such proof of the authenticity of the signature and of
      authority to transfer and of payment of transfer taxes as the Corporation
      or its agents may require.

(b)   The Corporation shall be entitled to treat the holder of record of any
      shares as the absolute owner thereof for all purposes, and, accordingly,
      shall not be bound to recognize any legal, equitable or other claim to, or
      interest in, such share or shares on the part of any other person, whether
      or not it shall have express or other notice thereof, except as otherwise
      expressly provided by law.

SECTION 4 - RECORD DATE:
------------------------

In lieu of closing the share records of the Corporation, the Board of Directors
may fix, in advance, a date not exceeding sixty days, nor less than ten days, as
the record date for the


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determination of shareholders entitled to receive notice of, or to vote at, any
meeting of shareholders, or to consent to any proposal without a meeting, or for
the purpose of determining shareholders entitled to receive payment of any
dividends, or allotment of any rights, or for the purpose of any other action.
If no record date is fixed, the record date for the determination of
shareholders entitled to notice of or to vote at a meeting of shareholders shall
be at the close of business on the day next preceding the day on which notice is
given, or, if no notice is given, the day on which the meeting is held; the
record date for determining shareholders for any other purpose shall be at the
close of business on the day on which the resolution of the directors relating
thereto is adopted. When a determination of shareholders of record entitled to
notice of or to vote at any meeting of shareholders has been made as provided
for herein, such determination shall apply to any adjournment thereof, unless
the directors fix a new record date for the adjournment meeting.

                             ARTICLE VI - DIVIDENDS
                             ----------------------

Subject to applicable law, dividends may be declared and paid out of any funds
available therefor, as often, in such amounts, and at such time or times as the
Board of Directors may determine.

                            ARTICLE VII - FISCAL YEAR
                            -------------------------

The fiscal year of the Corporation shall be fixed by the Board of Directors from
time to time, subject to applicable law.

                          ARTICLE VIII - CORPORATE SEAL
                          -----------------------------

The corporate seal, if any, shall be in such form as shall be approved from time
to time by the Board of Directors.

                            ARTICLE IX - AMENDMENTS
                            -----------------------

SECTION 1 - BY SHAREHOLDERS:
----------------------------

All by-laws of the Corporation shall be subject to alteration or repeal, and new
by-laws may be made, by a majority vote of the shareholders at the time entitled
to vote in the election of directors.

SECTION 2 - BY DIRECTORS:
-------------------------

The Board of Directors shall have power to make, adopt, alter, amend and repeal,
from time to time, by-laws of the Corporation; provided, however, that the
shareholders entitled to vote with respect thereto as in this Article IX
above-provided may alter, amend or repeal by-laws made by the Board of
Directors, except that the Board of Directors shall have no power to change the
quorum for meeting of shareholders or of the Board of


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Directors, or to change any provisions of the by-laws with respect to the
removal of directors or the filling of vacancies in the Board resulting from the
removal by the shareholders.

                           ARTICLE X - INDEMNIFICATION
                           ---------------------------

Subject to the conditions and qualifications set forth in the Business
Corporation Law, the Corporation may indemnify any person, made a party to an
action by or in the right of the Corporation to procure a judgment in its favor
by reason of the fact that he, his testator or intestate, is or was a director
or officer of the Corporation, against the reasonable expenses, including
attorneys fees, actually and necessarily incurred by him in connection with the
defense of such action, or in connection with an appeal therein, except in
relation to matters as to which such director or officer is adjudged to have
breached his duty to the Corporation, as such duty is defined in Section 717 of
the Business Corporation Law. Subject to the conditions and qualifications set
forth in the Business Corporation Law, the Corporation may also indemnify any
person, made or threatened to be made a party to an action or proceeding other
than one by or in the right of the Corporation to procure a judgment in its
favor, whether civil or criminal, including an action by or in the right of any
other corporation, domestic or foreign, which he served in any capacity at the
request of the Corporation, by reason of the fact, that he, his testator or
intestate was a director or officer of the Corporation or served such other
corporation in any capacity, against judgments, fines, amounts paid in
settlement, and reasonable expenses, including attorneys' fees actually and
necessarily incurred as a result of such action or proceeding, or any appeal
therein, if such director or officer acted in good faith for a purpose which he
reasonably believed to be in the best interests of the Corporation and, in
criminal actions or proceedings, in addition, had no reasonable cause to believe
that his conduct was unlawful.






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