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                                                                    EXHIBIT 4.27

                                EIGHTH AMENDMENT
                                       TO
                         RECEIVABLES PURCHASE AGREEMENT

               THIS EIGHTH AMENDMENT, dated as of August 8, 2002 (this
"Amendment"), to the Receivables Purchase Agreement dated as of May 14, 1999 (as
in effect on the date hereof, the "Receivables Purchase Agreement"), among
AMERISOURCE RECEIVABLES FINANCIAL CORPORATION, a Delaware corporation (the
"Seller"), AMERISOURCE CORPORATION, a Delaware corporation (the "Servicer" or
"AmeriSource"), AMERISOURCE HEALTH CORPORATION, a Delaware corporation (the
"Guarantor"), DELAWARE FUNDING CORPORATION, a Delaware corporation (with its
successors and assigns, the "Buyer"), and JPMORGAN CHASE BANK, a banking
corporation organized under the laws of the State of New York, as administrative
agent (with its successors and assigns, the "Administrative Agent") for the
Owners (as defined in the Receivables Purchase Agreement), is by and among the
parties listed above. Unless otherwise defined in this Amendment, capitalized
terms shall have the meanings assigned to such terms in the Receivables Purchase
Agreement.

                                 R E C I T A L S

               WHEREAS, the parties to the Receivables Purchase Agreement wish
to make certain amendments to the Receivables Purchase Agreement as set forth
herein.

               NOW THEREFORE, in consideration of the premises and mutual
covenants contained herein, and for good and sufficient consideration, the
parties hereto, intending to be legally bound, do hereby agree as follows:

         SECTION 1. Amendments to Section 1.01 of the Receivables Purchase
Agreement.

         (i)   The defined term "Dilution Reserve Percentage" appearing in
         Section 1.01 of the Receivables Purchase Agreement is hereby deleted
         and replaced with the following:

         "Dilution Reserve Percentage" shall mean, for any Monthly Period (as
         calculated in the Monthly Report required to be delivered in the month
         following such Monthly Period), a percentage calculated as of the last
         day of such Monthly Period, equal to the greater of (i) 7% and (ii) the
         product of:

                       ((2.0 * ED) + ((DS - ED) * DS / ED)) * DP

         Where:

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         ED  =  the average of the Dilution Ratios during the preceding twelve
         Monthly Periods ending on the last day of the Monthly Period for which
         such Dilution Percentage is established;

         DS  =  the highest Dilution Ratio for any Monthly Period during the
         preceding twelve consecutive Monthly Periods ending on the last day of
         the Monthly Period for which such Dilution Reserve Percentage is
         established;

         DP  =  a fraction the numerator of which is the product of (i) the
         aggregate amount of all Receivables which arose during such Monthly
         Period and (ii) DSO divided by 30, and the denominator of which is the
         Net Receivables Balance as of the last day of such Monthly Period; and

         DSO  =  the number of calendar days equal to the product of (i) 91 and
         (ii) a fraction the numerator of which is the Net Receivables Balance
         as of the last day of such Monthly Period, and the denominator of which
         is the aggregate amount of all Receivables which arose during the
         preceding three consecutive Monthly Periods ending on the last day of
         the Monthly Period for which such Dilution Reserve Percentage is
         established.

         (ii) The defined terms "Dilution Spike" and "Expected Dilution" are
         hereby deleted from Section 1.01 of the Receivables Purchase Agreement.

         SECTION 2. Addition of New Section 2.06A to the Receivables Purchase
Agreement. The Receivables Purchase Agreement is hereby amended by inserting the
following new Section 2.06A immediately after Section 2.06 therein:

         Section 2.06A. Pooled Funding of Net Investment. Notwithstanding
         anything to the contrary contained in this Agreement, if the Buyer
         funds all or a portion of the Net Investment through the issuance of
         Commercial Paper, it may (in its sole discretion) elect to do so
         through the issuance of Commercial Paper tranches the proceeds of which
         are not used exclusively for the purpose of funding the Net Investment
         hereunder (a "Pooled Funding"). To the extent the Buyer (in the
         exercise of its sole discretion) funds all or a portion of the Net
         Investment on a Pooled Funding basis, (i) the Seller shall have no
         right to request Tranche Periods, (ii) the Tranche Rate for the portion
         of the Net Investment funded on a Pooled Funding basis shall be, for
         each day, the rate equivalent of the weighted average of the rates
         payable on all Commercial Paper of the Buyer issued on a Pooled Funding
         basis on such day, converted (as necessary) to an annual yield
         equivalent rate on the basis of a 360-day year, which rates shall
         include any dealer's discount or fees and any other fees attributable
         thereto, (iii) the portion of the Net Investment funded on a Pooled
         Funding basis shall be deemed to be allocated to a Tranche with a
         Tranche Period maturing on the last calendar day of each calendar
         month, (iv) if the report delivered by the Administrative Agent to the
         Seller pursuant to Section 2.07 includes an estimate with respect to a
         Tranche funded on a Pooled Funding basis, the Administrative Agent
         shall deliver a revised report to the Seller on or before the last
         calendar day of the applicable calendar month and the Seller shall pay
         the Discount shown thereon on the last calendar

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         day of such calendar month, and (v) the other terms and provisions of
         this Agreement shall be construed and applied in a manner consistent
         with this Section 2.06A (whether or not such terms and provisions are
         referenced with specificity in this Section 2.06A) and all Pooled
         Funding shall be administered by the Administrative Agent in accordance
         with its general policies and procedures applicable to Pooled Funding.

         SECTION 3. Receivables Purchase Agreement in Full Force and Effect, as
Amended. Except as specifically stated herein, all of the terms and conditions
of the Receivables Purchase Agreement shall remain in full force and effect. All
references to the Receivables Purchase Agreement in any Purchase Document or any
other document or instrument shall be deemed to mean the Receivables Purchase
Agreement, as amended by this Amendment. This Amendment shall not constitute a
novation of the Receivables Purchase Agreement, but shall constitute an
amendment thereto. The parties hereto agree to be bound by the terms and
obligations of the Receivables Purchase Agreement, as amended by this Amendment,
as though the terms and obligations of the Receivables Purchase Agreement were
set forth herein.

         SECTION 4. Effectiveness. This Amendment shall become effective as of
the date hereof, upon receipt by the Administrative Agent of an executed
counterpart of this Amendment from each party hereto (including the
acknowledgement and consent of JPMorgan Chase Bank, as Agent for the APA
Purchasers).

         SECTION 5. Counterparts. This Amendment may be executed in any number
of counterparts and by separate parties hereto on separate counterparts
(including by way of facsimile transmission), each of which when executed shall
be deemed an original, but all such counterparts taken together shall constitute
one and the same instrument.

         SECTION 6. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

                            [Signature Page Follows]

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed and delivered by their duly authorized officers as of the date first
above set forth.

                                   DELAWARE FUNDING CORPORATION

                                   By: JPMorgan Chase Bank, as attorney-in-fact
                                       for Delaware Funding Corporation

                                   By _______________________________________
                                      Name:
                                      Title:

                                   JPMORGAN CHASE BANK, as Administrative Agent

                                   By _______________________________________
                                      Name:
                                      Title:

                                   AMERISOURCE RECEIVABLES FINANCIAL CORPORATION

                                   By _______________________________________
                                      Name:
                                      Title:

                                   AMERISOURCE CORPORATION

                                   By _______________________________________
                                      Name:
                                      Title:

                                   AMERISOURCE HEALTH CORPORATION

                                   By _______________________________________
                                      Name:
                                      Title:

ACKNOWLEDGED AND CONSENTED TO:

JPMORGAN CHASE BANK, as Agent
for the APA Purchasers

By__________________________
   Name:
   Title:

    [Signature Page to Eighth Amendment to AmeriSource Receivables Purchase
                                   Agreement]