EXHIBIT 3.10

                                                                       Exhibit A
                                                                       ---------

                                    BY-LAWS

                                       OF

                     SCHEIN PHARMACEUTICAL SERVICE COMPANY

                                  ----------

                                   ARTICLE I

                                    OFFICES

          SECTION 1. REGISTERED OFFICE.--The registered office shall be
established and maintained at the office of The Prentice-Hall Corporation
System, Inc., in the City of Dover, in the County of Kent, in the State of
Delaware, and said corporation shall be the registered agent of this corporation
in charge thereof.

          SECTION 2. OTHER OFFICES.--The corporation may have other offices,
either within or without the State of Delaware, at such place or places as the
Board of Directors may from time to time appoint or the business of the
corporation may require.

                                   ARTICLE II

                            MEETINGS OF STOCKHOLDERS

          SECTION 1. ANNUAL MEETINGS.--Annual meetings of stockholders for the
election of directors and for such other business as may be stated in the notice
of the meeting, shall be held at such place, either within or without the State
of Delaware, and at such time and date as the Board of Directors, by resolution,
shall determine and as set forth in the notice of the meeting.

          If the date of the annual meeting shall fall upon a legal holiday, the
meeting shall be held on the next succeeding business day. At each annual
meeting, the stockholders entitled to vote shall elect a Board of Directors and
they may transact such other corporate business as shall be stated in the notice
of the meeting.

          SECTION 2. OTHER MEETINGS.--Meetings of stockholders for any purpose
other than the election of directors may be held at such time and place, within
or without the State of Delaware, as shall be stated in the notice of the
meeting.

 
          SECTION 3. VOTING.--Each stockholder entitled to vote in accordance
with the terms of the Certificate of Incorporation and these By-Laws shall be
entitled to one vote, in person or by proxy, for each share of stock entitled to
vote held by such stockholder, but no proxy shall be voted after three years
from its date unless such proxy provides for a longer period. Upon the demand of
any stockholder, the vote for directors and the vote upon any question before
the meeting, shall be by ballot. All elections for directors shall be decided by
plurality vote; all other questions shall be decided by majority vote except as
otherwise provided by the Certificate of Incorporation or the laws of the State
of Delaware.

          A complete list of the stockholders entitled to vote at the ensuing
election, arranged in alphabetical order, with the address of each, and the
number of shares held by each, shall be open to the examination of any
stockholder, for any purpose germane to the meeting, during ordinary business
hours for a period of at least ten days prior to the meeting, either at a place
within the city where the meeting is to be held, which place shall be specified
in the notice of the meeting, or, if not so specified, at the place where the
meeting is to be held. The list shall also be produced and kept at the time and
place of the meeting during the whole time thereof, and may be inspected by any
stockholder who is present.

          SECTION 4. QUORUM.--Except as otherwise required by law, by the
Certificate of Incorporation or by these By-Laws, the presence, in person or by
proxy, of stockholders holding a majority of the stock of the corporation
entitled to vote shall constitute a quorum at all meetings of the stockholders.
In case a quorum shall not be present at any meeting, a majority in interest of
the stockholders entitled to vote thereat, present in person or by proxy, shall
have power to adjourn the meeting from time to time, without notice other than
announcement at the meeting, until the requisite amount of stock entitled to
vote shall be present. At any such adjourned meeting at which the requisite
amount of stock entitled to vote shall be represented, any business may be
transacted which might have been transacted at the meeting as originally
noticed; but only those stockholders entitled to vote at the meeting as
originally noticed shall be entitled to vote at any adjournment or adjournments
thereof.

          SECTION 5. SPECIAL MEETINGS.--Special meetings of the stockholders
for any purpose or purposes maybe called by the President or Secretary, or by
resolution of the directors or by vote of the stockholders holding twenty-five
(25) percent or more of the outstanding stock of the corporation.

          SECTION 6. NOTICE OF MEETINGS.--Written notice, stating the place,
date and time of the meeting, and the general nature of the business to be
considered, shall be given

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to each stockholder entitled to vote thereat at his address as it appears on the
records of the corporation, not less than ten nor more than sixty days before
the date of the meeting. No business other than that stated in the notice shall
be transacted at any meeting without the unanimous consent of all the
stockholders entitled to vote thereat.

          SECTION 7. ACTION WITHOUT MEETING.--Unless otherwise provided by the
Certificate of Incorporation, any action required to be taken at any annual or
special meeting of stockholders, or any action which may be taken at any annual
or special meeting, may be taken without a meeting, without prior notice and
without a vote, if a consent in writing, setting forth the action so taken,
shall be signed by the holders of outstanding stock having not less than the
minimum number of votes that would be necessary to authorize or take such action
at a meeting at which all shares entitled to vote thereon were present and
voted. Prompt notice of the taking of the corporate action without a meeting by
less than unanimous written consent shall be given to those stockholders who
have not consented in writing.

                                  ARTICLE III

                                   DIRECTORS

          SECTION 1. NUMBER AND TERM.--The number of directors constituting the
Board of Directors shall be not more than nine nor less than one, as fixed from
time to time by action of the stockholders or the Board of Directors. The
directors shall be elected at the annual meeting of the stockholders and each
director shall be elected to serve until his or her successor shall be elected
and shall qualify. Directors need not be stockholders.

          SECTION 2. RESIGNATIONS.--Any director, member of a committee or other
officer may resign at any time. Such resignation shall be made in writing, and
shall take effect at the time specified therein, and if no time be specified, at
the time of its receipt by the President or Secretary. The acceptance of a
resignation shall not be necessary to make it effective.

          SECTION 3. VACANCIES.--If the office of any director, member of a
committee or other officer becomes vacant, the remaining directors in office,
though less than a quorum by a majority vote, may appoint any qualified person
to fill such vacancy, who shall hold office for the unexpired term and until his
successor shall be duly chosen provided, however, that if there are no directors
then in office due to such a vacancy, the stockholders may elect a successor who
shall hold office for the unexpired term and until his successor shall be
elected and qualified.

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          SECTION 4. REMOVAL.--Except as hereinafter provided, any director or
directors may be removed either for or without cause at any time by the
affirmative vote of the holders of a majority of all the shares of stock
outstanding and entitled to vote, at a special meeting of the stockholders
called for the purpose and the vacancies thus created may be filled, at the
meeting held for the purpose of removal, by the affirmative vote of a majority
in interest of the stockholders entitled to vote.

          Unless the Certificate of Incorporation a otherwise provides,
stockholders may effect removal of a director who is a member of a classified
Board of Directors only for cause. If the Certificate of Incorporation provides
for cumulative voting and if less than the entire board is to be removed, no
director may be removed without cause if the votes cast against his removal
would be sufficient to elect him if then cumulatively voted at an election of
the entire board of directors, or, if there be classes of directors, at an
election of the class of directors of which he is a part.

          If the holders of any class or series are entitled to elect one or
more directors by the provisions of the Certificate of Incorporation, these
provisions shall apply, in respect to the removal without cause of a director or
directors so elected, to the vote of the holders of the outstanding shares of
that class or series and not to the vote of the outstanding shares as a whole.

          SECTION 5. INCREASE OF NUMBER.--The number of directors may be
increased by the affirmative vote of a majority of the directors, though less
than a quorum, or, by the affirmative vote of a majority in interest of the
stockholders, at the annual meeting or at a special meeting called for that
purpose, and by like vote the additional directors may be chosen at such meeting
to hold office until the next annual election and until their successors are
elected and qualify.

          SECTION 6. POWERS.--The Board of Directors shall exercise all of the
powers of the corporation except such as are by law, or by the Certificate of
Incorporation of the corporation or by these By-Laws conferred upon or reserved
to the stockholders.

          SECTION 7. COMMITTEES.--The Board of Directors may, by resolution or
resolutions passed by a majority of the whole board, designate one or more
committees, each committee to consist of one or more of the directors of the
corporation. The board may designate one or more directors as alternate members
of any committee, who may replace any absent or disqualified member at any
meeting of the committee. In the absence or disqualification of any member of
such committee or committees, the member or members thereof present at any
meeting and not disqualified from voting, whether or not he or they constitute a

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quorum, may unanimously appoint another member of the Board of Directors to act
at the meeting in the place of any such absent or disqualified member.

          Any such committee, to the extent provided in the resolution of the
Board of Directors, or in these By-Laws, shall have and may exercise all the
powers and authority of the Board of Directors in the management of the business
and affairs of the corporation, and may authorize the seal of the corporation to
be affixed to all papers which may require it; but no such committee shall have
the power or authority in reference to amending the Certificate of
Incorporation, adopting an agreement of merger or consolidation, recommending to
the stockholders the sale, lease or exchange of all or substantially all of the
corporation's property and assets, recommending to the stockholders a
dissolution of the corporation or a revocation of a dissolution, or amending the
By-Laws of the corporation; and, unless the resolution, these By-Laws or the
Certificate of Incorporation expressly so provide, no such committee shall have
the power or authority to declare a dividend or to authorize the issuance of
stock.

          SECTION 8. MEETINGS.--The newly elected directors may hold their first
meeting for the purpose of organization and the transaction of business, if a
quorum be present, immediately after the annual meeting of the stockholders; or
the time and place of such meeting may be fixed by consent in writing of all the
directors.

          Regular meetings of the directors may be held without notice at such
places and times as shall be determined from time to time by resolution of the
directors.

          Special meetings of the board may be called by the President or by the
Secretary on the written request of any two directors on at least two days'
notice to each director and shall be held at such place or places as may be
determined by the directors, or as shall be stated in the call of the meeting.

          Unless otherwise restricted by the Certificate of Incorporation or
these By-Laws, members of the Board of Directors, or any committee designated by
the Board of Directors, may participate in a meeting of the Board of Directors,
or any committee, by means of conference telephone or similar communications
equipment by means of which all persons participating in the meeting can hear
each other, and such participation in a meeting shall constitute presence in
person at the meeting.

          SECTION 9. QUORUM.--A majority of the directors shall constitute a
quorum for the transaction of business. If at any meeting of the board there
shall be less than a quorum present, a majority of those present may adjourn the

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meeting from time to time until a quorum is obtained, and no further notice
thereof need be given other than by announcement at the meeting which shall be
so adjourned.

          SECTION 10. COMPENSATION.--Directors shall not receive any stated
salary for their services as directors or as members of committees, but by
resolution of the board a fixed fee and expenses of attendance may be allowed
for attendance at each meeting. Nothing herein contained shall be construed to
preclude any director from serving the corporation in any other capacity as an
officer, agent or otherwise, and receiving compensation therefor.

          SECTION 11. ACTION WITHOUT MEETING.--Any action required or permitted
to be taken at any meting of the Board of Directors, or of any committee
thereof, may be taken without a meeting, if a written consent thereto is signed
by all members of the board, or of such committee as the case may be, and such
written consent is filed with the minutes of proceedings of the board or
committee.

                                   ARTICLE IV

                                    OFFICERS

          SECTION 1. OFFICERS.--The officers of the corporation shall be a
Chairman, a Chief Executive Officer, a President, a Vice President and a
Secretary, all of whom shall be elected by the Board of Directors and who shall
hold office until their successors are elected and qualified. In addition, the
Board of Directors may elect additional Vice-Presidents, a Treasurer and such
Assistant Secretaries and Assistant Treasurers as they may deem proper. None of
the officers of the corporation need be directors. The officers shall be elected
at the first meeting of the Board of Directors after each annual meeting. More
than two offices may be held by the same person. Any officer may be removed,
with or without cause, by the Board of Directors. Any vacancy may be filled by
the Board of Directors.

          SECTION 2. OTHER OFFICERS AND AGENTS.--The Board of Directors may
appoint such other officers and agents as it may deem advisable, who shall hold
their offices for such terms and shall exercise such powers and perform such
duties as shall be determined from time to time by the Board of Directors.

          SECTION 3. CHAIRMAN.--The Chairman of the Board of Directors, if one
be elected shall preside at all meetings of the Board of Directors and he shall
have and perform such other duties as from time to time may be assigned to him
by the Board of Directors.

          SECTION 4. PRESIDENT.--The President shall preside at all meetings of
the stockholders if present thereat,

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and in the absence or non-election of the Chairman of the Board of Directors,
at all meetings of the Board of Directors, and shall have general supervision,
direction and control of the business of the corporation subject to the
authorization and control of the Board of Directors. Except as the Board of
Directors shall authorize the execution thereof in some other manner, he shall
execute bonds, mortgages and other contracts on behalf of the corporation, and
shall cause the seal to be affixed to any instrument requiring it and when so
affixed the seal shall be attested by the signature of the Secretary or the
Treasurer or an Assistant Secretary or an Assistant Treasurer.

          SECTION 5. VICE-PRESIDENT.--Each Vice-President shall have such
powers and shall perform such duties as shall be assigned to him by the
directors.

          SECTION 6. TREASURERS.--The Treasurer shall have the custody of the
corporate funds and securities and shall keep full and accurate account of
receipts and disbursements in books belonging to the corporation. He shall
deposit all moneys and other valuables in the name and to the credit of the
corporation in such depositaries as may be designated by the Board of Directors.

          The Treasurer shall disburse the funds of the corporation as may be
ordered by the Board of Directors, or the President, taking proper vouchers for
such disbursements. He shall render to the President and Board of Directors at
the regular meetings of the Board of Directors, or whenever they may request it,
an account of all his transactions as Treasurer and of the financial condition
of the corporation. If required by the Board of Directors, he shall give the
corporation a bond for the faithful discharge of his duties in such amount and
with such surety as the board shall prescribe.

          SECTION 7. SECRETARY.--The Secretary shall give, or cause to be
given, notice of all meetings of stockholders and directors, and all other
notices required by law or by these By-Laws, and in case of his absence or
refusal or neglect so to do, any such notice may be given by any person
thereunto directed by the President, or by the directors, or stockholders, upon
whose requisition the meeting is called as provided in these By-Laws. He shall
record all the proceedings of the meetings of the corporation and of the
directors in a book to be kept for that purpose, and shall perform such other
duties as may be assigned to him by the directors or the President. He shall
have custody of the seal of the corporation and shall affix the same to all
instruments requiring it, when authorized by the directors or the President, and
attest the same.

          SECTION 8. ASSISTANT TREASURERS AND ASSISTANT SECRETARIES.--Assistant
Treasurers and Assistant Secretaries, if any, shall be elected and shall have
such powers and shall

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perform such duties as shall be assigned to them, respectively, by the
directors.

                                   ARTICLE V

                                 MISCELLANEOUS

          SECTION 1. CERTIFICATES OF STOCK.--Certificates of stock, signed by
the Chairman or Vice Chairman of the Board of Directors, if they be elected,
President or Vice-President, and the Treasurer or an Assistant Treasurer, or
Secretary or an Assistant Secretary, shall be issued to each stockholder
certifying the number of shares owned by him in the corporation. Any or all the
signatures may be facsimiles.

          SECTION 2. LOST CERTIFICATES.--A new certificate of stock may be
issued in the place of any certificate theretofore issued by the corporation,
alleged to have been lost or destroyed, and the directors may, in their
discretion, require the owner of the lost or destroyed certificate, or his legal
representatives, to give the corporation a bond, in such sum as they may direct,
not exceeding double the value of the stock, to indemnify the corporation
against any claim that may be made against it on account of the alleged loss of
any such certificate, or the issuance of any such new certificate.

          SECTION 3. TRANSFER OF SHARES.--The shares of stock of the corporation
shall be transferable only upon its books by the holders thereof in person or by
their duly authorized attorneys or legal representatives, and upon such transfer
the old certificates shall be surrendered to the corporation by the delivery
thereof to the person in charge of the stock and transfer books and ledgers, or
to such other person as the directors may designate, by whom they shall be
cancelled, and new certificates shall thereupon be issued. A record shall be
made of each transfer and whenever a transfer shall be made for collateral
security, and not absolutely, it shall be so expressed in the entry of the
transfer.

          SECTION 4. STOCKHOLDERS RECORD DATE.--In order that the corporation
may determine the stockholders entitled to notice of or to vote at any meeting
of stockholders or any adjournment thereof, or to express consent to corporate
action in writing without a meeting, or entitled to receive payment of any
dividend or other distribution or allotment of any rights, or entitled to
exercise any rights in respect of any change, conversion or exchange of stock or
for the purpose of any other lawful action, the Board of Directors may fix, in
advance, a record date, which shall not be more than sixty nor less than ten
days before the date of such meeting, nor more than sixty days prior to any
other action. A determination of stockholders of record entitled to notice of or
to vote at a meeting of

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stockholders shall apply to any adjournment of the meeting; provided, however,
that the Board of Directors may fix a new record date for the adjourned meeting.

          SECTION 5. DIVIDENDS.--Subject to the provisions of the Certificate of
Incorporation, the Board of Directors may, out of funds legally available
therefor at any regular or special meeting, declare dividends upon the capital
stock of the corporation as and when they deem expedient. Before declaring any
dividend there may be set apart out of any funds of the corporation available
for dividends, such sum or sums as the directors from time to time in their
discretion deem proper for working capital or as a reserve fund to meet
contingencies or for equalizing dividends or for such other purposes as the
directors shall deem conducive to the interests of the corporation.

          SECTION 6. SEAL.--The corporate seal shall be circular in form and
shall contain the name of the corporation, the year of its creation and the
words "CORPORATE SEAL DELAWARE." Said seal may be used by causing it or a
facsimile thereof to be impressed or affixed or reproduced or otherwise.

          SECTION 7. FISCAL YEAR.--The fiscal year of the corporation shall be
determined by resolution of the Board of Directors.

          SECTION 8. CHECKS.--All checks, drafts or other orders for the
payment of money, notes or other evidences of indebtedness issued in the name of
the corporation shall be signed by such officer or officers, agent or agents of
the corporation, and in such manner as shall be determined from time to time by
resolution of the Board of Directors.

          SECTION 9. NOTICE AND WAIVER OF NOTICE.--Whenever any notice is
required by these By-Laws to be given, personal notice is not meant unless
expressly so stated, and any notice so required shall be deemed to be sufficient
if given by depositing the same in the United States mail, postage prepaid,
addressed to the person entitled thereto at his address as it appears on the
records of the corporation, and such notice shall be deemed to have been given
on the day of such mailing. Stockholders not entitled to vote shall not be
entitled to receive notice of any meetings except as otherwise provided by
Statute.

          Whenever any notice whatsoever is required to be given under the
provisions of any law, or under the provisions of the Certificate of
Incorporation of the corporation or these By-Laws, a waiver thereof in writing,
signed by the person or persons entitled to said notice, whether before or after
the time stated therein, shall be deemed equivalent thereto.

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                                   ARTICLE VI

                                   AMENDMENTS

          These By-Laws may be altered or repealed and By-Laws may be made at
any annual meeting of the stockholders or at any special meeting thereof if
notice of the proposed alteration or repeal or By-Law or By-Laws to be made be
contained in the notice of such special meeting, by the affirmative vote of a
majority of the stock issued and outstanding and entitled to vote thereat, or by
the affirmative vote of a majority of the Board of Directors, at any regular
meeting of the Board of Directors, or at any special meeting of the Board of
Directors, if notice of the proposed alteration or repeal, or By-Law or By-Laws
to be made, be contained in the notice of such special meeting.

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