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                                                                     EXHIBIT 4.1

                          FIRST SUPPLEMENTAL INDENTURE


         FIRST SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE") dated
November 15, 2002, but effective as of August 30, 2001, by and among ADVANCEPCS
HEALTH SYSTEMS, L.L.C., a Delaware limited liability company, ADVANCEPCS
SPECIALTYRX, L.L.C., a Delaware limited liability company, DRESING-LIERMAN,
INC., an Ohio corporation, and THERACOM, INC., an Ohio corporation, (each, a
"GUARANTEEING SUBSIDIARY"), each, a subsidiary of AdvancePCS (the "COMPANY"),
and THE BANK OF NEW YORK TRUST COMPANY OF FLORIDA, N.A., successor trustee to
U.S. Trust Company of Texas, N.A., under the indenture referred to below (the
"TRUSTEE").

                                   WITNESSETH

         WHEREAS, the Company, the Trustee and certain Guarantors are parties to
an indenture (as amended and supplemented from time to time, the "INDENTURE"),
dated as of March 13, 2001, providing for the issuance of an aggregate principal
amount of up to $300,000,000 of 8 1/2% Senior Notes due 2008 (the "NOTES");

         WHEREAS, the Indenture provides that under certain circumstances, a
Subsidiary of the Company shall execute and deliver to the Trustee a
supplemental indenture pursuant to which such Subsidiary shall unconditionally
Guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "SUBSIDIARY GUARANTEE"); and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, each
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

         1. Capitalized Terms. Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

         2. Agreement to Guarantee. Subject to the terms and conditions of the
Indenture, each Guaranteeing Subsidiary hereby, jointly and severally with all
other Guarantors, unconditionally Guarantees to each Holder of a Note
authenticated and delivered by the Trustee and to the Trustee and its successors
and assigns, irrespective of the validity and enforceability of the Indenture,
the Notes or the Obligations of the Company thereunder, that:

                  (i) the principal of and interest on the Notes will be
         promptly paid in full when due, whether at maturity, by acceleration,
         redemption or otherwise, and interest on the overdue principal of and
         interest on the Notes, if any, if lawful, and all other



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         Obligations of the Company to the Holders or the Trustee thereunder
         will be promptly paid in full or performed, all in accordance with the
         terms hereof and thereof; and

                  (ii) in case of any extension of time of payment or renewal of
         any Notes or any of such other Obligations, that same will be promptly
         paid in full when due or performed in accordance with the terms of the
         extension or renewal, whether at stated maturity, by acceleration or
         otherwise.

         3. Execution and Delivery. Each Guaranteeing Subsidiary agrees that the
Subsidiary Guarantee shall remain in full force and effect notwithstanding any
failure to endorse on each Note a notation of such Subsidiary Guarantee.

         4. Releases. Guarantors may be released from their obligations under
the Indenture pursuant to Sections 4.16 and 11.04 of the Indenture.

         5. NEW YORK LAW TO GOVERN. THIS SUPPLEMENTAL INDENTURE SHALL BE
GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW
YORK.

         6. Counterparts. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

         7. Effect of Headings. The Section headings herein are for convenience
only and shall not affect the construction hereof.

         8. The Trustee. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this Supplemental
Indenture or for or in respect of the recitals contained herein, all of which
recitals are made solely by each Guaranteeing Subsidiary and the Company.



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         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be effective as of the date first above written.


                                       ADVANCEPCS HEALTH SYSTEMS, L.L.C.


                                       By:
                                                -------------------------------
                                       Name:    David D. Halbert
                                       Title:   CEO


                                       ADVANCEPCS SPECIALTYRX, L.L.C.

                                       By:
                                                -------------------------------
                                       Name:    David D. Halbert
                                       Title:   CEO


                                       DRESING-LIERMAN, INC.


                                       By:
                                                -------------------------------
                                       Name:    David D. Halbert
                                       Title:   CEO


                                       THERACOM, INC.


                                       By:
                                                -------------------------------
                                       Name:    David D. Halbert
                                       Title:   CEO


                                       THE BANK OF NEW YORK TRUST COMPANY
                                       OF FLORIDA, N.A., as Trustee


                                       By:
                                                -------------------------------

                                       Name:
                                                -------------------------------

                                       Title:
                                                -------------------------------




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