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                                                                     EXHIBIT 4.8

                            RPSA SUPPLEMENT AGREEMENT

     THIS RPSA SUPPLEMENT AGREEMENT (this "Supplement") is entered into as of
December 20, 2002, among Blue Hill II, Inc. ("Blue Hill"), Liberty Street
Funding Corp. (the "New Conduit Purchaser"), The Bank of Nova Scotia (the "New
Committed Purchaser", and together with the New Conduit Purchaser, the New
Purchasers"), and The Bank of Nova Scotia (the "New Purchaser Agent"), and is
consented to by General Electric Capital Corporation ("GECC") as administrative
agent (in such capacity, the "Administrative Agent") and each of the existing
"Purchasers" set forth on the signature pages hereto ("Existing Purchasers").

     Reference is made to the Amended and Restated Receivables Purchase and
Servicing Agreement, dated as of December 20, 2002 (as the same may be amended,
restated, supplemented and otherwise modified from time to time, the "Purchase
Agreement") among Blue Hill as seller, AmerisourceBergen Drug Corporation, as
successor by merger to Bergen Brunswig Drug Company, as servicer, Redwood
Receivables Corporation ("Redwood") as a conduit purchaser, the financial
institutions from time to time party thereto as conduit purchasers ("Conduit
Purchasers"), committed purchasers ("Committed Purchasers") and purchaser agents
("Purchaser Agents"), and GECC as a Committed Purchaser, as a Purchaser Agent,
and as administrative agent for the Conduit Purchasers, the Committed Purchasers
and the Purchaser Agents. Capitalized terms used but not otherwise defined
herein have the meanings given to such terms in Amended and Restated Annex X to
Sale and Contribution Agreement and Amended and Restated Receivables Purchase
and Servicing Agreement dated as of December 20, 2002 (as the same may be
amended, restated, supplemented and otherwise modified from time to time, "Annex
X").

                             Preliminary Statements

          A. Upon the Restatement Effective Date, the Maximum Purchase Limit
under the Purchase Agreement shall be increased by $250,000,000 to be
$700,000,000.

          B. Blue Hill desires that the New Purchasers become parties to the
Purchase Agreement in order to make Purchases of Transferred Receivables
thereunder in connection with the increased Maximum Purchase Limit.

          C. The New Purchasers desire to become parties to the Purchase
Agreement.

          D. Pursuant to Section 14.08(b) of the Purchase Agreement, Blue Hill
may add additional Persons as "Purchasers" to the Purchase Agreement.

          NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is acknowledged, the parties hereto agree as follows:

          1. Upon the terms and conditions set forth in the Purchase Agreement,
the New Purchasers agree to become Purchasers thereunder, the New Purchaser
Agent agrees to become a Purchaser Agent thereunder, and the New Committed
Purchaser agrees to undertake a Commitment in the amount set forth under its
signature hereto.

          2. Blue Hill represents and warrants that (a) all of the
representations and warranties of it contained in the Purchase Agreement and the
other Related Documents are true and correct in all respects on and as of the
Effective Date hereof, as if then made (other than representations and

                                                         The Bank of Nova Scotia
                                                       RPSA Supplement Agreement

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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 Supplement.

          3. Each of the New Purchasers (a) represents and warrants to Blue Hill
and to the Administrative Agent that independently and without reliance upon the
Administrative Agent, the Purchaser Agents, or any other Purchaser and based on
such documents and information as it has deemed appropriate, it has made and
will continue to make its own appraisal of and investigation into the business,
operations, property, prospects, financial and other conditions and
creditworthiness of Blue Hill, the Servicer or the Originator, and the
Receivables and its own decision to enter into the Purchase Agreement and to
take, or omit, action under any Related Document; (b) confirms that it has
received a copy of the Purchase Agreement and the Sale and Contribution
Agreement, and such other documents and information as it has deemed appropriate
to make its own credit analysis and decision to enter into this Supplement; (c)
appoints the Purchaser Agent as its agent to take such action on each such New
Purchaser's behalf and to carry out such functions under the Purchase Agreement
and the other Related Documents as are delegated to the Purchaser Agent by the
terms thereof, or are reasonably incidental thereto; (d) appoints the
Administrative Agent as its agent to take such action on each such New
Purchaser's behalf and to carry out such functions under the Purchase Agreement
and the other Related Documents as are delegated to the Administrative Agent by
the terms thereof, or are reasonably incidental thereto; (e) agrees that it will
perform in accordance with their terms all of the obligations which by the terms
of the Purchase Agreement are required to be performed by it as a Committed
Purchaser or a Conduit Purchaser, as applicable; and (f) specifies as its
address for notices the office set forth beneath its name on the signature pages
hereof.

          4. Schedule I hereto, and made a part hereof, sets forth additional
terms and conditions that will apply specifically to the New Purchasers in their
capacities as a Purchasers under the Purchase Agreement.

          5. The effective date for this Supplement shall be the date on which
(a) Blue Hill and each member of the New Purchasers' Purchaser Group receive
this Supplement executed by the parties hereto; (b) all conditions set forth in
Section 14.08(b) have been satisfied, including, without limitation, obtaining
the consent of the Administrative Agent and each of the other Purchasers; (c)
the Administrative Agent receives counterparts of this Supplement executed by
each of the parties hereto; and (d) the Restatement Effective Date occurs (the
"Effective Date").

          6. From and after the Effective Date, (a) each of the New Purchasers
shall become a party to the Purchase Agreement as a Committed Purchaser and/or a
Conduit Purchaser, as applicable, for all purposes, shall have the rights and
obligations of a Committed Purchaser and/or a Conduit Purchaser, as applicable,
thereunder as if an original party thereto; (b) the New Purchase Agent shall
become a party to the Purchase Agreement as a Purchaser Agent, for all purposes,
and shall have the rights and obligations of a Purchaser Agent thereunder as if
an original party thereto.

          7. Each party hereto covenants and agrees that, from and after the
Effective Date and until the date one year plus one day following the date on
which the Commercial Paper with the latest maturity has been indefeasibly paid
in full in cash, it will not, directly or indirectly, institute or cause to be
instituted against any Conduit Purchaser or any Committed Purchaser any
proceeding of the type referred to in Sections 9.01(c) and 9.01(d) of the
Purchase Agreement. This Section 7 shall survive the termination of this
Supplement.

                                                         The Bank of Nova Scotia
                                                       RPSA Supplement Agreement

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          8.  THIS SUPPLEMENT, 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.

          9.  This Supplement contains the final and complete integration of all
prior expressions by the parties hereto with respect to the subject matter
hereof and shall constitute the entire agreement among the parties hereto with
respect to the subject matter hereof superseding all prior oral or written
understandings.

          10. If any one or more of the covenants, agreements, provisions or
terms of this Supplement shall for any reason whatsoever be held invalid, then
such covenants, agreements, provisions, or terms shall be deemed severable from
the remaining covenants, agreements, provisions, or terms of this Supplement and
shall in no way affect the validity or enforceability of the other provisions of
this Supplement.

          11. This Supplement may be executed in any number of counterparts and
by different parties hereto in separate counterparts, each of which when so
executed shall be deemed to be an original and all of which when taken together
shall constitute one and the same agreement.

          12. This Supplement shall be binding on the parties hereto and their
respective successors and assigns.

                                      * * *

                                                         The Bank of Nova Scotia
                                                       RPSA Supplement Agreement

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     IN WITNESS WHEREOF, the parties hereto have caused this RPSA Supplement
Agreement to be executed by their respective officers thereunto duly authorized
as of the date first above written.

BLUE HILL II, INC.                      LIBERTY STREET FUNDING CORP., as New
                                        Conduit Purchaser


By: ______________________________      By: ____________________________________
      Name:                                   Name:
      Title:                                  Title:

                                        Address for Notices:
                                              Name:
                                              Address:
                                              Attention:
                                              Telephone:
                                              Facsimile:



THE BANK OF NOVA SCOTIA, as New
Committed Purchaser and New
Purchaser Agent


By: ______________________________
      Name:
      Title:

Commitment: $250,000,000

Address for Notices:
      Name:
      Address:
      Attention:
      Telephone:
      Facsimile:

                                Signature Page to
                             The Bank of Nova Scotia
                            RPSA Supplement Agreement

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ACKNOWLEDGED AND AGREED:

GENERAL ELECTRIC CAPITAL CORPORATION,
as Administrative Agent


By: ____________________________________
      Name:
      Title: Duly Authorized Signatory


GENERAL ELECTRIC CAPITAL CORPORATION,
as a Committed Purchaser and a Purchaser Agent


By: ____________________________________
      Name:
      Title: Duly Authorized Signatory


REDWOOD RECEIVABLES CORPORATION,
as a Conduit Purchaser


By: ____________________________________
      Name:
      Title: Assistant Secretary

                                Signature Page to
                             The Bank of Nova Scotia
                            RPSA Supplement Agreement

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                                                  Schedule I to Exhibit 14.08(b)
                                                           to Purchase Agreement
New Committed Purchaser's Commitment:        $250,000,000

New Purchasers' Purchaser Group Commitment:  $250,000,000


Additional Terms and Conditions:
-------------------------------

     Notwithstanding anything to the contrary in the Purchase Agreement, when
used in the Purchase Agreement in connection with the New Purchasers, the New
Purchaser Agent, The New Purchasers' Purchaser Group, the New Committed
Purchaser's Commitment, the New Purchasers' Group Commitment or the New
Purchasers' Capital Investment, the following terms shall have the meanings set
forth below:

     "Committed Purchaser Daily Yield Rate" shall mean, with respect to the
Committed Purchaser who is The Bank of Nova Scotia, for any day during a
Settlement Period, (a) the weighted average Scotia Yield Rates applicable to
such Committed Purchaser's Capital Investment on such day, weighted by such
Committed Purchaser's outstanding Capital Investment, divided by (b) 360.

     "Committed Purchaser Expiry Date" shall mean, with respect to the Committed
Purchaser who is The Bank of Nova Scotia, February 28, 2003, as such date may be
extended from time to time in accordance with Section 2.13(a) of the Purchase
Agreement.

     "Scotia Yield Rate" shall mean, with respect to the Capital Investment of
the Committed Purchaser who is The Bank of Nova Scotia, for any day during a
Settlement Period, (a) if the LIBOR market is closed, or if such Committed
Purchaser's Purchaser Agent determines that it is illegal for the Committed
Purchaser to make Purchases accruing interest at a rate based upon LIBOR, the
sum of (i) the rate of interest most recently announced by The Bank of Nova
Scotia at its office in New York, New York as its prime rate, such rate to
change as and when such designated rate changes (with the understanding that
such rate may merely serve as a basis upon which effective rates of interest are
calculated for loans making reference to such prime rate and that such rate is
not necessarily the lowest or best rate at which The Bank of Nova Scotia
calculates interest or extends credit) plus (ii) the Used Commitment Fee (as
such term is defined in such Committed Purchaser's Purchaser Group Fee Letter)
plus (iii) if a Termination Event has occurred and is continuing, the Daily
Default Margin, or (b) the sum of (i) LIBOR plus (ii) the Used Commitment Fee
(as such term is defined in such Committed Purchaser's Purchaser Group Fee
Letter) plus (iii) if a Termination Event has occurred and is continuing, the
Daily Default Margin.

     "Conduit Purchaser Daily Yield Rate" shall mean, with respect to the
Conduit Purchaser who is Liberty Street Funding Corp., on any day, the floating
per annum rate equal to the sum of (a) the Used Commitment Fee (as defined in
such Conduit Purchaser's Purchaser Group Fee Letter) plus (b) if a Termination
Event has occurred and is continuing, the Daily Default Margin plus (c) the
weighted average cost (as determined by such Conduit Purchaser's Purchaser Agent
and which shall include commissions of placement agents and dealers, incremental
carrying costs incurred with respect to Commercial Paper maturing on dates other
than those on which corresponding funds are received by such

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Conduit Purchaser, other borrowings by such Conduit Purchaser (other than under
any Program Document) and any other costs associated with the issuance of
Commercial Paper) of or related to the issuance of Commercial Paper that are
allocated, in whole or in part, by such Conduit Purchaser or such Conduit
Purchaser's Purchaser Agent to fund or maintain such Conduit Purchaser's Capital
Investment (and which may also be allocated in part to the funding of other
assets of such Conduit Purchaser); provided, however, that if any component of
such rate is a discount rate, in calculating the "Conduit Purchaser Daily Yield
Rate", such Conduit Purchaser's Purchaser Agent shall for such component use the
rate resulting from converting such discount rate to an interest bearing
equivalent rate per annum; provided, further, that if any Conduit Purchaser
other than Liberty Street Funding Corp. elects not to make a Purchase under
Section 2.01(a) of the Purchase Agreement for any reason other than solely
because another Conduit Purchaser elects not to make a Purchase pursuant to such
Section, the rate set forth in item (c) of this definition shall be the
Committed Purchaser Daily Yield Rate for the Committed Purchaser who is The Bank
of Nova Scotia.

     "LIBOR" shall mean, with respect to the Committed Purchaser who is The Bank
of Nova Scotia, for any Settlement Period, (a) the interest rate per annum shown
on the BBAM page of the Bloomberg Financial Markets Services Display Screen or
any successor page as the average British Bankers' Association Interest
Settlement Rate for deposits in Dollars with a period comparable to such
Settlement Period and for delivery on the first day of such Settlement Period,
as of 11:00 a.m. (London time) two Business Days prior to the first day of such
Settlement Period, or (b) if the screen described in clause (a) above shall
cease to be publicly available, the interest rate per annum shown on page 3750
of the Dow Jones & Company Telerate screen or any successor page as the
composite offered rate for London interbank deposits with a period comparable to
such Settlement Period, as shown under the heading "USED" at 11:00 a.m. (London
time) two Business Days prior to the first day of such Settlement Period, or (c)
if the rates in clauses (a) and (b) shall cease to be publicly available, the
average interest rate per annum offered to such Committed Purchaser's Purchaser
Agent in the interbank market for Dollar deposits of amounts in funds comparable
to the principal amount of such Committed Purchaser's Capital Investment to
which such LIBOR is to be applicable with maturities comparable to the
Settlement Period for which LIBOR will apply as of approximately 1:00 p.m. (New
York time) two Business Days prior to the commencement of such Settlement
Period. The LIBOR shall be set using five decimal places.