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                                                                     EXHIBIT 4.5

                               THIRD AMENDMENT TO

                         SALE AND CONTRIBUTION AGREEMENT

          THIS THIRD AMENDMENT TO SALE AND CONTRIBUTION AGREEMENT, dated as of
December 20, 2002 (this "Third Amendment") relates to that certain Sale and
Contribution Agreement dated as of December 20, 2000, between Blue Hill and the
Originator (each as defined below), as amended by the First Amendment to Sale
and Contribution Agreement dated as of October 1, 2002 and as amended by the
Second Amendment to Sale and Contribution Agreement dated as of December 2, 2002
(the "Sale and Contribution Agreement"), and is entered into by and between BLUE
HILL II, INC., a Delaware corporation ("Blue Hill") and AMERISOURCEBERGEN DRUG
CORPORATION (f/k/a AmeriSource Corporation), a Delaware corporation, as
successor by merger to Bergen Brunswig Drug Company, a California corporation,
as the originator (in such capacity, the "Originator"). Capitalized terms used
and not otherwise defined herein shall have the meanings assigned to them in
Amended and Restated Annex X to the Sale and Contribution Agreement dated as of
December 20, 2000, and the Amended and Restated Receivables Purchase and
Servicing Agreement dated as of December 20, 2002 (as the same may be amended,
restated, supplemented, or otherwise modified from time to time, "Annex X").

                               W I T N E S S E T H

          WHEREAS, Blue Hill and the Originator have entered into the Sale and
Contribution Agreement;

          WHEREAS, Blue Hill, the Servicer, the Purchasers and the
Administrative Agent have entered into the Purchase Agreement;

          WHEREAS, Blue Hill desires to (a) add additional parties as
"Purchasers" to the Purchase Agreement so that such parties may make Purchases
of Purchaser Interests pursuant to the Purchase Agreement, (b) increase the
Maximum Purchase Limit available to Blue Hill thereunder, (c) add other
additional parties as "Purchaser Agents" to the Purchase Agreement to act as
agents to the "Purchasers" in order to facilitate the Purchases under the
Purchase Agreement and (d) provide for the ability of the Purchasers to assign
their interests thereunder from time to time;

          WHEREAS, Blue Hill and Originator (collectively, the "Parties") have
mutually requested that the Sale and Contribution Agreement be amended (the
"Amendments") to reflect the addition of parties as "Purchasers" and "Purchaser
Agents" to the Purchase Agreement; and

          WHEREAS, the Parties are willing to so effect the Amendments on the
terms and conditions set forth herein.

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

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          NOW, THEREFORE, in consideration of the above premises, the Parties
agree as follows:

     1.   Definitions and Usage. Any reference herein to Section, Exhibit or
Schedule shall, unless otherwise specified, refer to such Section, Exhibit or
Schedule hereof, in its entirety.

     2.   Amendments to the Sale and Contribution Agreement. Upon the Third
Amendment Effective Date, the Sale and Contribution Agreement is hereby amended
as follows:

          a.   By amending Section 3.4 by (i) adding the phrase ", any Purchaser
     Agent's" after the phrase "Administrative Agent's" and (ii) deleting the
     phrase "Neither the Seller, the Administrative Agent nor any Purchaser" in
     its entirety and substituting in its stead the phrase "None of the Seller,
     the Administrative Agent, the Purchaser Agents and the Purchasers".

          b.   By amending Section 5.2(e) by adding the phrase "and the
     Purchaser Agents" after the phrase "the Administrative Agent".

          c.   By amending Section 5.2(o) by adding the phrase ", the Purchaser
     Agents" after the phrase "the Purchasers".

          d.   By amending Section 6.1(e) by (i) adding the phrase "or any
     Purchaser Agent" after the first reference to the phrase "the
     Administrative Agent", and (ii) adding the phrase ", the Purchaser Agents"
     after each reference therein to "the Servicer".

          e.   By amending Section 6.1(l) by adding the phrase ", the Purchaser
     Agents" after the phrase "the Buyer".

          f.   By amending Section 6.1(m) by adding the phrase ", the Purchaser
     Agents" after each reference therein to "the Servicer".

          g.   By deleting Section 6.1(o) in its entirety and substituting the
     following in its stead:

          (o)  No Proceedings. From and after the Closing Date and until the
          date one year plus one day following the date on which the Commercial
          Paper allocable to Buyer with the latest maturity has been
          indefeasibly paid in full in cash, the Originator shall not, directly
          or indirectly, institute or cause to be instituted against Buyer or
          any Purchaser any proceeding of the type referred to in Sections
          9.01(c) and 9.01(d) of the Purchase Agreement. The Originator
          acknowledges and agrees that no Conduit Purchaser shall, nor shall be
          obligated to, pay any amount pursuant to the Related Documents unless
          (i) such Conduit Purchaser has received funds which may be used to
          make such payment pursuant to the Program Documents, and (ii) after
          giving effect to such payment, either (A) such Conduit Purchaser could
          issue Commercial Paper to refinance all outstanding Commercial Paper
          (assuming such outstanding Commercial

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

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          Paper matured at such time) issued by such Conduit Purchaser without
          violating the Program Documents, or (B) all Commercial Paper issued by
          such Conduit Purchaser is paid in full. Any amount which a Conduit
          Purchaser does not pay pursuant to the operation of the preceding
          sentence shall not constitute a claim (as defined in Section 101 of
          the Bankruptcy Code) against or an obligation of such Conduit
          Purchaser for any insufficiency unless and until such Conduit
          Purchaser satisfies the provisions of such preceding sentence. This
          Section 6.1(o) shall survive the termination of this Agreement.

          h.   By amending Section 8.2 by (i) adding the phrase "and the
     Purchaser Agents" after the first and second references to "Purchasers",
     (ii) adding the phrase "nor any Purchaser Agent" after the phrase "nor any
     Purchaser" and (iii) deleting the last sentence of Section 8.2 in its
     entirety and substituting the following in its stead:

          Originator hereby further acknowledges that the execution and
          performance of this Agreement are conditions precedent for the
          Administrative Agent, the Purchaser Agents and the Purchasers to enter
          into the Purchase Agreement and that the agreement of the
          Administrative Agent, the Purchaser Agents and Purchasers to enter
          into the Purchase Agreement will directly or indirectly benefit
          Originator and constitutes good and valuable consideration for the
          rights and remedies of the Administrative Agent, the Purchaser Agents
          and each Purchaser with respect hereto.

          i.   By amending Section 8.3 by adding the phrase "or Purchaser Agent"
     after the phrase "or any Purchaser".

          j.   By amending Section 8.9 (a) by (i) adding the phrase ", the
     Purchaser Agents" after the first reference therein to "the Administrative
     Agent", (ii) adding the phrase "any Purchaser Agent" after the third
     reference therein to "the Administrative Agent", and (iii) adding the
     phrase ", any Purchaser Agent" after the fourth and fifth references
     therein to "the Administrative Agent".

     3.   Representations and Warranties of the Originator and the Servicer.
Each of the Originator and the Servicer represents and warrants to Blue Hill
that, as of the Third Amendment Effective Date and after giving effect to this
Third Amendment:

          a.   All of the representations and warranties of the Originator and
     the Servicer contained in this Third Amendment, the Sale and Contribution
     Agreement and the other Related Documents are true and correct in all
     material respects on and as of the Third Amendment Effective Date, as if
     then made (other than representations and warranties which expressly speak
     as of a different date, which shall be true and correct in all material
     respects as of that date); and

          b.   No Termination Event or Incipient Termination Event has occurred
     and is continuing or will result after giving effect to this Third
     Amendment.

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

                                        3

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     4.   Effective Date. This Third Amendment shall become effective as of the
date first written above (the "Third Amendment Effective Date") upon the
satisfaction of each of the following conditions:

          a.   Blue Hill shall have received each of the following documents, in
     each case in form and substance satisfactory to Blue Hill and the
     Administrative Agent:

               i.    counterparts hereof executed by each of the Parties;

               ii.   satisfactory evidence of the effectiveness of the Amended
          and Restated Agreement and Annex X, dated as of the date hereof, among
          Blue Hill, the Servicer, the Administrative Agent, the Purchaser
          Agents and the Purchasers, together with delivery of an execution copy
          thereof and of the other documents delivered in connection therewith;

               iii.  an executed Amended and Restated Fee Letter, dated as of
          the date hereof, between Blue Hill, GE Capital as Administrative
          Agent, a Purchaser Agent and a Committed Purchaser, and Redwood.

               iv.   an executed RPSA Supplement Agreement, dated as of the date
          hereof, between Blue Hill, Liberty Street Funding Corp. as a Conduit
          Purchaser, The Bank of Nova Scotia as a Committed Purchaser, and The
          Bank of Nova Scotia as Purchaser Agent for the aforementioned Conduit
          Purchaser and Committed Purchaser.

               v.    a certificate of an officer of the Originator attesting to
          the solvency of Originator;

               vi.   a certificate of an officer of the Originator certifying,
          among other things, that the representations and warranties contained
          in the Related Documents are correct as of the date hereof;

               vii.  a certificate of the Secretary or Assistant Secretary of
          the Originator certifying no change in the certificate of
          incorporation of the Originator and bylaws of the Originator, and
          certifying and attaching resolutions authorizing the Third Amendment
          and an incumbency certificate;

               viii. tax and good standing certificates of the Seller in the
          states of California, and Delaware;

               ix.   tax and good standing certificates of the Originator in the
          state of California, Pennsylvania and Delaware;

               x.    a legal opinion as to security interests, enforceability,
          corporate matters and non-contravention delivered by Dechert, and in
          addition, a legal opinion delivered by the in-house counsel of the
          Originator and Buyer, both, after giving effect to the Third
          Amendment;

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

                                     4

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               xi.   such additional documentation as the Buyer may reasonably
          request;

          b.   No law, regulation, order, judgment or decree of any Governmental
     Authority shall, and no Party shall have received any notice that
     litigation is pending or threatened which is likely to, enjoin, prohibit or
     restrain the consummation of the transactions contemplated by this Third
     Amendment, except for such laws, regulations, orders or decrees, or pending
     or threatened litigation, that in the aggregate could not reasonably be
     expected to have a Material Adverse Effect;

          c.   All of the representations and warranties of Blue Hill and the
     Servicer contained in this Third Amendment and the other Related Documents
     shall be true and correct in all material respects on and as of the Third
     Amendment Effective Date, as if then made (other than representations and
     warranties which expressly speak as of a different date, which shall be
     true and correct in all material respects as of that date);

          d.   All corporate and other proceedings, and all documents,
     instruments and other legal matters in connection with the transactions
     contemplated by this Third Amendment shall be satisfactory in all respects
     in form and substance to the Buyer; and

          e.   No Termination Event or Incipient Termination Event shall have
     occurred and be continuing on the Third Amendment Effective Date or will
     result after giving effect to this Third Amendment.

     5.   Reference to and Effect on the Related Documents.

          a.   Upon the Third Amendment Effective Date, (i) each reference in
     the Sale and Contribution Agreement to "this Agreement", "hereunder",
     "hereof" or phrase of like import, and each reference in the Related
     Documents to the Sale and Contribution Agreement shall mean and be a
     reference to the Sale and Contribution Agreement as amended and
     supplemented hereby.

          b.   Except to the extent specifically set forth herein, the
     respective provisions of the Sale and Contribution Agreement and the other
     Related Documents shall not be amended, modified, waived, impaired or
     otherwise affected hereby, and such documents and the Obligations under
     each of them are hereby confirmed as being in full force and effect.

          c.   This Third Amendment shall be limited solely to the matters
     expressly set forth herein and shall not (i) constitute an amendment or
     waiver of any other term or condition of the Sale and Contribution
     Agreement or any other Related Document, (ii) prejudice any right or rights
     which any of the Parties, the Administrative Agent or the Purchasers may
     now have or may have in the future under or in connection with the Sale and
     Contribution Agreement or any other Related Document, (iii) require any of
     the Parties, the Administrative Agent, the Purchaser Agents or the
     Purchasers to agree to a similar transaction on a future occasion or (iv)
     create any right herein to another

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

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     Person or other beneficiary or otherwise, except to the extent specifically
     provided herein.

     6.   Acknowledgement of Amendment and Restatement. The Originator and Blue
Hill acknowledge and consent to the amendment and restatement of Annex X in the
form attached hereto as Annex I.

     7.   Miscellaneous. This Third Amendment is a Related Document. The
headings herein are for convenience of reference only and shall not alter or
otherwise affect the meaning hereof.

     8.   Section Titles. The Section titles in this Third Amendment are and
shall be without substantive meaning or content of any kind whatsoever and are
not a part of the agreement between the parties hereto.

     9.   Counterparts. This Third Amendment may be executed in any number of
counterparts and by the different parties hereto in separate counterparts, each
of which when so executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument.

     10.  GOVERNING LAW. THIS THIRD AMENDMENT, AND ALL MATTERS OF CONSTRUCTION,
VALIDITY AND PERFORMANCE HEREOF, SHALL BE GOVERNED BY, AND CONSTRUED AND
ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

     11.  No Strict Construction. The parties hereto have participated jointly
in the negotiation and drafting of this Third Amendment. In the event an
ambiguity or question of intent or interpretation arises, this Third Amendment
shall be construed as if drafted jointly by the parties hereto and no
presumption or burden of proof shall arise favoring or disfavoring any party by
virtue of the authorship of any provisions of this Third Amendment.

                                     * * * *

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT

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          IN WITNESS WHEREOF, Blue Hill and the Originator have caused this
Third Amendment to be executed by their respective officers thereunto duly
authorized as of the date first above written.

                                      BLUE HILL II, INC.,
                                      as Buyer

                                      By: ______________________________
                                          Name:
                                          Title:


                                      AMERISOURCEBERGEN DRUG CORPORATION,
                                      a Delaware corporation, as successor by
                                      merger to Bergen Brunswig Drug Company, a
                                      California corporation, as Originator and
                                      as Servicer



                                      By: ______________________________
                                          Name:
                                          Title:

ACKNOWLEDGED AND AGREED:

GENERAL ELECTRIC CAPITAL
CORPORATION,
as Administrative Agent

By: _______________________________
    Name: Brian P. Schwinn
    Title: Duly Authorized Signatory

                                                              THIRD AMENDMENT TO
                                                 SALE AND CONTRIBUTION AGREEMENT