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                                                                    EXHIBIT 10.1


                               AMENDMENT NO. 6 TO
                              THE CREDIT AGREEMENT

                  AMENDMENT NO. 6 TO THE CREDIT AGREEMENT (this "Amendment")
dated as of September 13, 2002 is entered into by and among AdvancePCS, f/k/a
Advance Paradigm, Inc., a Delaware corporation (the "Borrower"), the Subsidiary
Guarantors party hereto, the Lenders party hereto, Bank One, N.A. ("Bank One"),
as Documentation Agent, Bank of America, N.A. ("Bank of America"), as Collateral
Agent and as Administrative Agent for the Lender Parties, Merrill Lynch, Pierce,
Fenner & Smith Incorporated, as Book-Runner, Lead Arranger and Syndication
Agent, and Banc of America Securities LLC, as Joint Book-Runner and Joint Lead
Arranger. Capitalized terms not otherwise defined in this Amendment have the
same meanings as specified in the Credit Agreement (as defined below).

                  PRELIMINARY STATEMENTS:

                  WHEREAS, the Borrower, the Subsidiary Guarantors, the Lenders
and the Agents have entered into a Credit Agreement dated as of October 2, 2000,
as amended by Amendment No. 1 to the Credit Agreement dated as of November 3,
2000, Amendment No. 2 to the Credit Agreement dated as of June 22, 2001,
Amendment No. 3 to the Credit Agreement dated as of August 24, 2001, Amendment
No. 4 to the Credit Agreement dated as of May 29, 2002 and Amendment No. 5 to
the Credit Agreement dated as of July 17, 2002 (as so amended and as otherwise
amended, restated and modified from time to time, the "Credit Agreement"); and

                  WHEREAS, the Borrower has requested that the Credit Agreement
be amended so as to permit an increase in the amount of the Tranche A Revolving
Credit Facility from $175,000,000 to up to $275,000,000; and

                  WHEREAS, such amendment to the Credit Agreement requires the
consent of the Required Lenders; and

                  WHEREAS, the Borrower and its Subsidiaries have requested that
the Required Lenders approve such amendment to the Credit Agreement as described
herein.

                  NOW, THEREFORE, in consideration of the mutual promises and
obligations contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Borrower, the
Subsidiary Guarantors and the Required Lenders have agreed to amend the Credit
Agreement as hereinafter set forth.

                  SECTION 1. Amendments.

                  (a) The Credit Agreement is, effective as of the Amendment
         No. 6 Effective Date (as defined herein), hereby amended by adding
         immediately after Section 2.16 a new Section 2.17 to read as follows:



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                  2.17 Increase in Tranche A Revolving Credit Facility.

                           (a) Provided there exists no Default, upon notice to
                  the Administrative Agent (which shall promptly notify the
                  Lenders if the Borrower has not already done so), the Borrower
                  may from time to time until and including October 31, 2002,
                  request an increase in the Tranche A Revolving Credit Facility
                  by an amount for all such requests not exceeding $100,000,000
                  in the aggregate (i.e., the amount of the Tranche A Revolving
                  Credit Facility may be increased up to $275,000,000); provided
                  that any such request must be in an amount of not less that
                  $5,000,000 and in a whole multiple of $1,000,000 in excess
                  thereof. Each Lender shall notify the Borrower and the
                  Administrative Agent whether or not it agrees to increase its
                  Tranche A Revolving Credit Commitment and, if so, by what
                  amount. The Administrative Agent shall notify each Lender of
                  the Lenders' responses to each request made hereunder. To
                  achieve the full amount of a requested increase, the Borrower
                  may also invite additional Eligible Assignees to become
                  Lenders pursuant to a joinder agreement in form and substance
                  satisfactory to the Administrative Agent and its counsel.

                           (b) If the Tranche A Revolving Credit Facility is
                  increased in accordance with this Section, the Administrative
                  Agent and the Borrower shall determine one or more effective
                  dates (any such date an "Increase Effective Date") and the
                  final allocation of any such increase. The Administrative
                  Agent shall promptly notify the Borrower and the Lenders of
                  the final allocation of any such increase and the relevant
                  Increase Effective Date. As a condition precedent to any such
                  increase, the Borrower shall deliver to the Administrative
                  Agent a certificate dated as of the relevant Increase
                  Effective Date signed by a Responsible Officer of the Borrower
                  (i) certifying and attaching the resolutions adopted by the
                  Borrower approving or consenting to such increase, and (ii)
                  certifying that, before and after giving effect to such
                  increase, (A) the representations and warranties contained in
                  Article IV and the other Loan Documents are true and correct
                  on and as of the relevant Increase Effective Date, except to
                  the extent that such representations and warranties
                  specifically refer to an earlier date, in which case they are
                  true and correct as of such earlier date, and (B) no Default
                  exists. The Borrower shall prepay any Tranche A Revolving
                  Credit Advances outstanding on the relevant Increase Effective
                  Date (and pay any additional amounts required pursuant to
                  Section 9.04(c)) to the extent necessary to keep the
                  outstanding Tranche A Revolving Credit Advances ratable with
                  any revised Pro Rata Shares arising from any nonratable
                  increase in the Tranche A Revolving Credit Commitments under
                  this Section.


                  (b) Section 9.04(c) of the Credit Agreement is hereby amended
         by (i) replacing the words "or 2.10(d)" with ", 2.10(d) or 2.17" and
         (ii) replacing the words "or 6.01" with ", 2.17 or 6.01".

                  SECTION 2. Conditions of Effectiveness. This Amendment shall
become effective as of the date first above written (the "Amendment No. 6
Effective Date") when, and




                                       2
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only when, each of the following conditions shall have been satisfied (it being
understood that the satisfaction of one or more of the following conditions may
occur concurrently with the effectiveness of this Amendment):

                      (a) the Administrative Agent shall have received
         counterparts of this Amendment executed by the Borrower, the Subsidiary
         Guarantors and the Required Lenders or, as to any of the Required
         Lenders, advice satisfactory to the Administrative Agent that such
         Required Lender has executed this Amendment;

                      (b) the Borrower shall have paid any and all out-of-pocket
         costs (to the extent invoiced) incurred by the Administrative Agent
         (including the reasonable fees and expenses of the Administrative
         Agent's legal counsel), and fees and other amounts payable to the
         Administrative Agent, in each case in connection with the arrangement,
         negotiation, preparation, execution and delivery of this Amendment; and

                      (c) the Administrative Agent shall be satisfied that, as
         of the date the last of the conditions set forth in this Section 2 is
         satisfied, (i) all representations and warranties made by the Borrower
         and each other Loan Party in this Amendment and each other Loan
         Document are true and correct in all material respects as if made as of
         such date, other than any such representations or warranties that, by
         their terms, refer to a specific date other than the date hereof, in
         which case as of such specific date, and (ii) after giving effect to
         this Amendment, no Default or Event of Default has occurred and is
         continuing.

                  SECTION 3. Authority of Administrative Agent. The Required
Lenders hereby acknowledge and agree that pursuant to the authority granted to
the Administrative Agent under Article VIII of the Credit Agreement, the
Administrative Agent has the power to execute and deliver all documents and to
take all such further action on behalf of the Lender Parties as it may deem to
be reasonably necessary to effectuate this Amendment.

                  SECTION 4. Representations and Warranties. Each of the Loan
Parties represents and warrants as follows:

                      (a) the representations and warranties contained in each
         Loan Document are correct in all material respects on and as of the
         date hereof, before and after giving effect to this Amendment, as
         though made on and as of the date hereof, other than any such
         representations or warranties that by their terms, refer to a specific
         date, in which case, as of such specific date;

                      (b) no Default or Event of Default has occurred and is
         continuing under the Credit Agreement, as amended hereby, or would
         result from this Amendment;

                      (c) it has taken all necessary action to authorize the
         execution, delivery and performance of this Amendment;

                      (d) this Amendment has been duly executed and delivered by
         such Loan Party and constitutes such Loan Party's legal, valid and
         binding obligation, enforceable in



                                       3
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         accordance with its terms, except as such enforceability may be limited
         (x) by general principles of equity and conflicts of laws or (y) by
         bankruptcy, reorganization, insolvency, moratorium or other laws of
         general application relating to or affecting the enforcement, of
         creditors' rights;

                      (e) no consent, approval, authorization or order of, or
         filing, registration or qualification with, any court or governmental
         authority or third party is required in connection with the execution,
         delivery or performance by such Loan Party of this Amendment where not
         completed such action would reasonably be expected to have a Material
         Adverse Effect; and

                      (f) the execution and delivery of this Amendment does not
         diminish or reduce its obligations under the Loan Documents (including,
         without limitation, in the case of each Subsidiary Guarantor, such
         Subsidiary Guarantor's guaranty pursuant to Section 7 of the Credit
         Agreement) in any manner, except as specifically set forth herein.

                  SECTION 5. Reference to and Effect on the Loan Documents.

                      (a) On and after the effectiveness of this Amendment, each
         reference in the Credit Agreement to "this Agreement", "hereunder",
         "hereof" or words of like import referring to the Credit Agreement, and
         each reference in the Notes and each of the other Loan Documents to
         "the Credit Agreement", "thereunder", "thereof" or words of like import
         referring to the Credit Agreement, shall mean and be a reference to the
         Credit Agreement as amended by this Amendment.

                      (b) The Credit Agreement, the Notes and each of the other
         Loan Documents, as specifically amended by this Amendment, are and
         shall continue to be in full force and effect and are hereby in all
         respects ratified and confirmed.

                      (c) Except as expressly provided herein, the execution,
         delivery and effectiveness of this Amendment shall not operate as a
         waiver of any right, power or remedy of any Lender or the
         Administrative Agent under any of the Loan Documents, nor constitute a
         waiver of any provision of any of the Loan Documents.

                      (d) This Amendment shall constitute a Loan Document and,
         as such, can only be amended in accordance with the provisions of
         Section 9.01 of the Credit Agreement.

                  SECTION 6. Costs, Expenses. The Borrower agrees to pay on
demand all reasonable costs and expenses of the Administrative Agent in
connection with the preparation, execution, delivery and administration of this
Amendment (including, without limitation, the reasonable fees and expenses of
counsel for the Administrative Agent) in accordance with the terms of Section
9.04 of the Credit Agreement.

                  SECTION 7. Execution in Counterparts. This Amendment 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 taken together shall



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constitute but one and the same agreement. Delivery of an executed counterpart
of a signature page to this Amendment by telecopier shall be effective as
delivery of a manually executed counterpart of this Amendment.

             SECTION 8. Governing Law. This Amendment shall be governed by, and
construed in accordance with, the laws of the State of New York.


              [The rest of this page is intentionally left blank.]




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



                                        BORROWER


                                             ADVANCEPCS

                                             By:
                                                --------------------------------
                                             Name:
                                             Title:

                                        SUBSIDIARY GUARANTORS


                                        ADVANCEPCS HOLDING CORPORATION

                                             By:
                                                --------------------------------
                                             Name:
                                             Title:

                                        ADVANCEPCS HEALTH SYSTEMS, LLC


                                             By:
                                                --------------------------------
                                             Name:
                                             Title:

                                        ADVANCEPCS HEALTH, L.P.

                                        By ADVANCEPCS HEALTH SYSTEMS, LLC, its
                                        General Partner


                                             By:
                                                --------------------------------
                                             Name:
                                             Title:




<PAGE>
                                     ADVANCEPCS RESEARCH, L.L.C.

                                     By:
                                        ----------------------------------------
                                     Name:
                                     Title:


                                     ADVANCERX.COM, L.P.


                                     By ADVANCEPCS HEALTH SYSTEMS, LLC, its
                                     General Partner

                                     By:
                                        ----------------------------------------
                                     Name:
                                     Title:


                                     ADVP CONSOLIDATION, L.L.C.

                                     By:
                                        ----------------------------------------
                                     Name:  Susan de Mars
                                     Title: General Counsel and Secretary


                                     ADVP MANAGEMENT, L.P.

                                     By ADVANCEPCS HEALTH SYSTEMS, LLC, its
                                     General Partner

                                     By:
                                        ----------------------------------------
                                     Name:
                                     Title:


                                     AMBULATORY CARE REVIEW SERVICES, INC.

                                     By:
                                        ----------------------------------------
                                     Name:
                                     Title:


                                     BAUMEL-EISNER NEUROMEDICAL INSTITUTE, INC.

                                     By:
                                        ----------------------------------------
                                     Name:
                                     Title:



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                                    FFI RX MANAGED CARE, INC.

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    FIRST FLORIDA INTERNATIONAL HOLDINGS, INC.

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    HMN HEALTH SERVICES, INC.

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    ADVANCEPCS MAIL SERVICES OF BIRMINGHAM, INC.

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    ADVANCEPCS PUERTO RICO, INC.

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    ADVANCEPCS SPECIALTYRX, LLC

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:

                                    AFC RECEIVABLES HOLDING CORPORATION

                                    By:
                                       ----------------------------------------
                                    Name:
                                    Title:



<PAGE>



                                           DRESING-LIERMAN, INC.

                                           By:
                                              ----------------------------------
                                           Name:
                                           Title:

                                           THERACOM, INC.

                                           By:
                                              ----------------------------------
                                           Name:
                                           Title:

                                           CONSUMER HEALTH INTERACTIVE, INC.

                                           By:
                                              ----------------------------------
                                           Name:
                                           Title:



<PAGE>

ADMINISTRATIVE AGENT AND COLLATERAL AGENT

BANK OF AMERICA, N.A.,
as Administrative Agent and Collateral Agent

By:
   -----------------------------------------
Title:



<PAGE>
LENDERS (AND OTHER AGENTS)

BANK OF AMERICA, N.A.,
as Initial Lender and Initial Issuing Bank and Lender Party


By:
   -------------------------------------
Title:


BANK ONE, N.A., as Documentation Agent and Lender Party


By:
   -------------------------------------
Title:


MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED,
as Syndication Agent and Lender Party


By:
   -------------------------------------
Title:




<PAGE>



----------------------------------------
[LENDER]

By:
   -----------------------------------------------------------
Title:
      --------------------------------------------------------