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                                                                   EXHIBIT 10.68

                        CAREMARK RX, INC. TRUST AGREEMENT

                           DATED AS OF MARCH 15, 2001

                                  BY AND AMONG

                               CAREMARK RX, INC.,

                           CAREMARK INTERNATIONAL INC.

                                  CAREMARK INC.

                                       AND

                       LASALLE BANK NATIONAL ASSOCIATION,
                                   AS TRUSTEE


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                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                                                <C>
SECTION 1 Definitions and Other Matters...........................................................................  3

SECTION 2 Actionable Default; Remedies............................................................................  5

         2.1      Notice of Default; Written Instructions.........................................................  5

         2.2      Remedies........................................................................................  5

         2.3      Right to Initiate Judicial Proceedings, etc.....................................................  6

         2.4      Appointment of a Receiver.......................................................................  6

         2.5      Exercise of Powers..............................................................................  6

         2.6      Control by Holders..............................................................................  6

         2.7      Remedies Not Exclusive..........................................................................  7

         2.8      Waiver of Certain Rights........................................................................  7

         2.9      Limitation on Trustee's Duties in Respect of Collateral.........................................  8

         2.10     Limitation by Law...............................................................................  8

         2.11     Absolute Rights of Holders; Equal and Ratable Security..........................................  8

SECTION 3 Trust Account, L/C Cash Collateral Account, Application Of Moneys.......................................  9

         3.1      The Trust Account; L/C Cash Collateral Account..................................................  9

         3.2      Control of Trust Account and L/C Cash Collateral Account........................................  9

         3.3      Investment of Funds Deposited in Trust Account and L/C Cash Collateral Account..................  9

         3.4      Application of Moneys in Trust Account and L/C Cash Collateral Account.......................... 10

         3.5      Application of Moneys Distributable to Holders of Senior Public Notes........................... 12

SECTION 4 Agreements With The Trustee............................................................................. 12

         4.1      Delivery of Debt Instruments.................................................................... 12

         4.2      Information as to Holders....................................................................... 12

         4.3      Compensation and Expenses....................................................................... 12

         4.4      Stamp and Other Similar Taxes................................................................... 13
</TABLE>


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<TABLE>
<S>                                                                                                                <C>
         4.5      Filing Fees, Excise Taxes, etc.................................................................. 13

         4.6      Indemnification................................................................................. 13

         4.7      Further Assurances; Notation on Financial Statements............................................ 13

SECTION 5 The Trustee............................................................................................. 14

         5.1      Acceptance of Trust............................................................................. 14

         5.2      Exculpatory Provisions.......................................................................... 14

         5.3      Delegation of Duties............................................................................ 15

         5.4      Reliance by Trustee............................................................................. 15

         5.5      Limitations on Duties of Trustee................................................................ 16

         5.6      Moneys to be Held in Trust...................................................................... 16

         5.7      Resignation and Removal of the Trustee.......................................................... 16

         5.8      Status of Successors to the Trustee............................................................. 17

         5.9      Merger of the Trustee........................................................................... 18

         5.10     Co-Trustee, Separate Trustee.................................................................... 18

SECTION 6 Release of Collateral................................................................................... 19

         6.1      Conditions to Release; Release Procedure........................................................ 19

SECTION 7 Miscellaneous........................................................................................... 20

         7.1      Amendments, Supplements and Waivers............................................................. 20

         7.2      Notices......................................................................................... 21

         7.3      Headings........................................................................................ 22

         7.4      Severability.................................................................................... 22

         7.5      Treatment of Payee or Indorsee by Trustee....................................................... 22

         7.6      Dealings with the Trustors...................................................................... 22

         7.7      Claims Against the Trustee...................................................................... 23

         7.8      Binding Effect.................................................................................. 23
</TABLE>


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<TABLE>
<S>                                                                                                                <C>
         7.9      Governing Law................................................................................... 23

         7.10     Counterparts.................................................................................... 24
</TABLE>


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                        CAREMARK RX, INC. TRUST AGREEMENT

                  CAREMARK RX, INC. TRUST AGREEMENT (this "AGREEMENT") dated as
of March 15, 2001, by and among Caremark Rx, Inc., a Delaware corporation (the
"COMPANY"), the subsidiaries of the Company listed in the signature pages hereto
(the "SUBSIDIARIES"), the ADDITIONAL TRUSTORS (as defined in Section 4.7, and
together with the Company and the Subsidiaries, the "TRUSTORS"), and LaSalle
Bank National Association, a national banking association (the "TRUSTEE"), as
Trustee hereunder for the holders of the Secured Debt (as defined below).

                             PRELIMINARY STATEMENTS:

                  (1)      The Company has issued $450,000,000 of its 7 3/8%
Senior Notes due 2006 (the "SENIOR PUBLIC NOTES") pursuant to an Indenture dated
as of October 8, 1996 (as supplemented from time to time, the "INDENTURE") among
the Company and U.S. Bank National Association (as successor to The First
National Bank of Chicago), as Trustee, (the "PUBLIC TRUSTEE").

                  (2)      The Company entered into a $1,000,000,000 Amended and
Restated Credit Agreement dated as of June 9, 1998, as amended (the "EXISTING
CREDIT AGREEMENT") with the financial institutions party thereto as lenders,
swing line banks and issuing banks, Credit Lyonnais New York Branch, The First
National Bank of Chicago and Morgan Guaranty Trust Company of New York, as
syndication agents, Banc of America Securities LLC (formerly known as
NationsBanc Montgomery Securities LLC), as arranger and Bank of America, N.A.
(formerly known as NationsBank, N.A.) as administrative agent.

                  (3)      To replace the Existing Credit Agreement, the Company
has entered into a Credit Agreement dated as of March 15, 2001 (as hereafter
amended, supplemented, restated or otherwise modified from time to time, the
"CREDIT AGREEMENT" and, together with the Indenture, the "DEBT INSTRUMENTS")
among the banks, financial institutions and other institutional lenders from
time to time party thereto (the "PRIVATE LENDERS" or "HOLDERS OF BANK DEBT"),
J.P. Morgan Chase & Co., as syndication agent, First Union National Bank, as
documentation agent, Banc of America Securities LLC, as lead arranger and book
manager and Bank of America, N.A. as the initial issuing bank, swing line bank
and administrative agent (the "ADMINISTRATIVE AGENT"), and, in connection
therewith, the Subsidiaries guaranteed the Obligations of the Company thereunder
pursuant to a Guarantee dated the date hereof (as hereafter amended, restated,
supplemented or otherwise modified from time to time, the "GUARANTEE").

                  (4)      The Company from time to time may enter into interest
rate hedge agreements (the "HEDGE AGREEMENTS") with financial institutions (the
"HEDGE BANKS") party to the Credit Agreement to the extent permitted therein,
and the obligations of the Company thereunder will be guaranteed by the
Subsidiaries pursuant to the Guarantee.


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                  (5)      It is a condition precedent to the Private Lenders
entering into the Credit Agreement that the Company, the Subsidiaries and the
Trustee enter into this Trust Agreement and a Pledge and Security Agreement
dated as of the date hereof (as hereafter amended, restated, supplemented or
otherwise modified from time to time, the "SECURITY AGREEMENT") in order to
equally and ratably secure the payment of all of the Company's obligations owing
under the Credit Agreement and the documents delivered in connection therewith
and the Hedge Agreements and the obligations of the Subsidiaries and the
Additional Trustors under the Guarantee (the "BANK DEBT") and the payment of all
of the Company's obligations owing under the Senior Public Notes (the Bank Debt
and the Senior Public Notes being, collectively, the "SECURED DEBT").

                              DECLARATION OF TRUST:

                  NOW THEREFORE, in order to secure the Secured Debt and in
consideration of the premises and the mutual agreements set forth herein, the
Trustee hereby declares that it holds as trustee in trust under this Agreement
all of its right, title and interest in, to and under all the following (and the
Company and the Subsidiaries do hereby consent thereto):

                  (A)      the Security Agreement (together with all
         supplements, documents and filings related thereto collectively, the
         "SECURITY DOCUMENTS") and the collateral granted to the Trustee
         thereunder (the "PLEDGED COLLATERAL"); and

                  (B)      each agreement entered into and delivered pursuant to
         Section 4.7 or Section 7.1(b) and the collateral granted to the Trustee
         thereunder (the "SUPPLEMENTAL COLLATERAL"; and, together with the
         Pledged Collateral, the "COLLATERAL").

                  TO HAVE AND TO HOLD, the foregoing Pledged Collateral and the
entire Collateral (the right, title and interest of the Trustee in the Security
Documents and the Collateral being hereinafter referred to as the "TRUST
ESTATE") unto the Trustee and its successors in trust under this Agreement and
its assigns and the assigns of its successors in trust forever;

                  IN TRUST NEVERTHELESS, under and subject to the terms and
conditions herein set forth and for the benefit of the holders of the Secured
Debt and for the enforcement of the payment of all of the Secured Debt, and for
the performance of and compliance with the covenants and conditions of this
Agreement, the Debt Instruments and the Security Documents.

                  PROVIDED, HOWEVER, that these presents are upon the condition
that if the Company, the Subsidiaries, and the Additional Trustors, if any, and
their successors or assigns, shall satisfy all of the conditions set forth in
Section 6, then this Agreement, and the estates and rights assigned in the
Security Documents, shall cease, terminate and be void; otherwise they shall
remain and be in full force and effect.

                  IT IS HEREBY FURTHER COVENANTED AND DECLARED, that the Trust
Estate is to be held and applied by the Trustee, subject to the further
covenants, conditions and trusts hereinafter set forth.


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                                   SECTION 1

                          Definitions and Other Matters

                  (a)      The words "hereof", "herein" and "hereunder" and
words of similar import when used in this Agreement shall refer to this
Agreement as a whole and not to any particular provision of this Agreement and
section references are to this Agreement unless otherwise specified.

                  (b)      In each case herein where "Holders" are entitled to
vote on any matter or to instruct the Trustee, the Public Trustee shall so vote
or instruct the Trustee on behalf of the holders of the Senior Public Notes. In
each case herein where any payment or distribution is to be made or notice is to
be given to "Holders," such payments, distributions and notices in respect of
the Senior Public Notes shall be made to the Public Trustee for the benefit of
the holders thereof pursuant to the terms of the Indenture.

                  (c)      As used in this Agreement, the following terms shall
have the following meanings (such meanings to be equally applicable to both the
singular and the plural forms of the terms defined:

                  "ACTIONABLE DEFAULT" means (a) so long as any amount is owing
         under the Indenture or any commitment is outstanding under the Credit
         Agreement, (i) the acceleration pursuant to Section 6.01 of the Credit
         Agreement of the maturity of the Bank Debt or the non-payment thereof
         at the scheduled maturity thereof or, (ii) the non-payment at scheduled
         final maturity of the Senior Public Notes or the declaration prior to
         their stated maturity that all of the Senior Public Notes are due and
         payable pursuant to Section 502 of the Indenture and (b) at any time
         thereafter, the acceleration of all amounts due under a Hedge
         Agreement; provided that upon delivery of a Notice of Actionable
         Default, the Trustee may assume that an Actionable Default shall be
         deemed to be continuing unless the Notice of Actionable Default
         delivered with respect thereto shall have been withdrawn in a writing
         delivered to the Trustee by or on behalf of the Holder or Holders from
         or on behalf of which such Notice of Actionable Default was delivered,
         prior to the first date on which the Trustee commences the exercise of
         any remedy with respect to the Collateral following the receipt of such
         Notice of Actionable Default.

                  "BANKRUPTCY PROCEEDING" means that the Company or any of the
         Subsidiaries shall generally not pay its debts as such debts become
         due, or shall admit in writing its inability to pay its debts
         generally, or shall make a general assignment for the benefit of
         creditors; or any proceeding shall be instituted by or against the
         Company or any of the Subsidiaries seeking to adjudicate it a bankrupt
         or insolvent, or seeking liquidation, winding up, reorganization,
         arrangement, adjustment, protection, relief, or composition of it or
         its debts under any law relating to bankruptcy, insolvency or
         reorganization or relief of debtors, or seeking the entry of an order
         for relief or the appointment of a receiver, trustee, administrator or
         other similar official for it or for any substantial part of its
         property and assets and, in the case of any such proceeding instituted
         against it (but not instituted by it) that is being diligently
         contested by it in good faith, either such


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         proceeding shall remain undismissed or unstayed for a period of at
         least 60 consecutive days or any of the actions sought in such
         proceeding (including, without limitation, the entry of an order for
         relief against, or the appointment of a receiver, trustee, custodian or
         other similar official for, it or any substantial part of its property
         and assets) shall occur; or any event or action analogous to or having
         a substantially similar effect to any of the events or actions set
         forth above in this definition (other than a solvent reorganization)
         shall occur under the law of any jurisdiction applicable to the Company
         or any of the Subsidiaries; or the Company or any of the Subsidiaries
         shall take any corporate, partnership, limited liability company or
         other similar action to authorize any of the actions set forth above in
         this definition.

                  "DISTRIBUTION DATES" means the dates fixed by the Trustee (the
         first of which shall occur within 90 days after receipt of a Notice of
         Actionable Default that has not theretofore been withdrawn and the
         balance of which shall be monthly thereafter) for the distribution of
         all moneys held by the Trustee in the Trust Account.

                  "HOLDERS" means the registered holders of the Senior Public
         Notes, the holders of the Bank Debt and the Hedge Banks.

                  "MAJORITY HOLDERS" means, as of any date (A) so long as any
         amount is owing under the Indenture or any commitment is outstanding
         under the Credit Agreement, Holders holding Secured Debt representing
         more than 50% of each of (i) the aggregate unpaid principal amount of
         the Senior Public Notes then outstanding under the Indenture and (ii)
         the aggregate unpaid principal amount of the Bank Debt under the Credit
         Agreement plus the aggregate obligations available under outstanding
         letters of credit thereunder and (B) at any time thereafter, the Hedge
         Banks holding more than 50% of the aggregate unpaid amount under the
         Hedge Agreements based on a mark to market calculation as of the date
         of determination.

                  "NOTICE OF ACTIONABLE DEFAULT" means (A) so long as any amount
         is owing under the Indenture or any commitment is outstanding under the
         Credit Agreement, a written notice to the Trustee from the
         Administrative Agent in respect of an Actionable Default relating to
         the Credit Agreement or from the Public Trustee in respect of an
         Actionable Default relating to the Indenture and (B) at any time
         thereafter, a written notice to the Trustee from any Hedge Bank in
         respect of an Actionable Default relating to a Hedge Agreement.

                  "RESPONSIBLE OFFICER" means the chief executive officer, the
         president, the chief financial officer, the principal accounting
         officer or the treasurer (or the equivalent of any of the foregoing) of
         the Company or any of the Subsidiaries or any other officer, partner or
         member (or person performing similar functions) of the Company or any
         of the Subsidiaries responsible for overseeing the administration of,
         or reviewing compliance with, all or any portion of this Agreement or
         any of the Security Documents.

                  "TRUSTEE'S FEES" means all fees, costs and expenses of the
         Trustee of the type described in Sections 4.3, 4.4, 4.5 and 4.6 of this
         Agreement.


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                                    SECTION 2

                          Actionable Default; Remedies.

                  2.1      Notice of Default; Written Instructions.

                  (a)      Upon receipt of a Notice of Actionable Default, the
Trustee shall, within five days thereafter, notify the Public Trustee, the
Administrative Agent and each Hedge Bank that an Actionable Default exists.

                  (b)      Upon receipt of any written directions pursuant to
Section 2.6(a), the Trustee shall, within five days thereafter, send a copy
thereof to the Administrative Agent, the Public Trustee and each Hedge Bank.

                  2.2      Remedies.

                  (a)      If and only if the Trustee shall have received a
Notice of Actionable Default and such Notice of Actionable Default shall not
have been withdrawn in accordance with the provisions hereof, the Trustee shall
exercise the rights and remedies provided in this Agreement and in the Security
Documents.

                  (b)      The Trustors hereby waive presentment, demand,
protest or any notice (to the extent permitted by applicable law) of any kind in
connection with this Agreement, any Collateral or any Security Document.

                  (c)      The Trustors hereby irrevocably constitute and
appoint the Trustee and any officer or agent thereof, with full power of
substitution, as their true and lawful attorney-in-fact with full power and
authority in the name of the Company or any of the Subsidiaries, as applicable,
or in its own name, from time to time in the Trustee's discretion, upon the
occurrence and during the continuance of an Actionable Default, for the purpose
of carrying out the terms of this Agreement and the Security Documents, to take
any and all appropriate action and to execute any and all documents and
instruments that may be necessary or desirable to accomplish the purposes hereof
and thereof and, without limiting the generality of the foregoing, hereby gives
the Trustee the power and right on behalf of the Trustors, without notice to or
assent by any Trustor, to do the following:

                           (i)      to ask for, demand, sue for, collect,
         receive, recover, compromise and give acquittance and receipts for any
         and all moneys due or to become due upon or by virtue hereof and
         thereof,

                           (ii)     to receive, take, endorse, assign and
         deliver any and all checks, notes, drafts, acceptances, documents and
         other negotiable and non-negotiable instruments and chattel paper taken
         or received by the Trustee in connection herewith and therewith,

                           (iii)    to commence, file, institute, prosecute,
         defend, settle, compromise or adjust any claim, suit, action or
         proceeding with respect hereto and thereto or in connection herewith
         and therewith,


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                           (iv)     to sell, transfer, assign or otherwise deal
         in or with the Collateral or any part thereof as fully and effectually
         as if the Trustee were the absolute owner thereof, and

                           (v)      to do, at its option and at the expense and
         for the account of the Trustors, at any time or from time to time, all
         acts and things that the Trustee deems necessary to protect or preserve
         the Collateral or the Trust Estate and to realize upon the Collateral.

                  2.3      Right to Initiate Judicial Proceedings, etc.

                  If and only if the Trustee shall have received a Notice of
Actionable Default and such Notice of Actionable Default shall not have been
withdrawn in accordance with the provisions hereof:

                           (i)      the Trustee shall have the right and power
         to institute and maintain such suits and proceedings as it may deem
         appropriate to protect and enforce the rights vested in it by this
         Agreement and each Security Document, and

                           (ii)     the Trustee may, either after entry or
         without entry, proceed by suit or suits at law or in equity to enforce
         such rights and to foreclose upon the Collateral and to sell all or,
         from time to time, any of the Trust Estate under the judgment or decree
         of a court of competent jurisdiction.

                  2.4      Appointment of a Receiver.

                  If a receiver of the Trust Estate shall be appointed in
judicial proceedings, the Trustee may be appointed as such receiver.
Notwithstanding the appointment of a receiver, the Trustee shall be entitled to
retain possession and control of all cash held by or deposited with it or its
agents pursuant to any provision of this Agreement or any Security Document.

                  2.5      Exercise of Powers.

                  All of the powers, remedies and rights of the Trustee as set
forth in this Agreement may be exercised by the Trustee in respect of any
Security Document as though set forth at length therein and all the powers,
remedies and rights of the Trustee and the Holders as set forth in any Security
Document may be exercised from time to time as herein and therein provided.

                  2.6      Control by Holders.

                  (a) Subject to Section 2.6(b), if an Actionable Default shall
have occurred and be continuing and the Trustee shall have received a Notice of
Actionable Default with respect thereto, the Majority Holders shall have the
right, by an instrument in writing executed and delivered to the Trustee, to
direct the time, method and place of conducting any proceeding for any right or
remedy available to the Trustee, or of exercising any trust or power conferred
on the Trustee, or for the appointment of a receiver, or for the taking of any
action authorized by Section 2.


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                  (b)      The Trustee shall not follow any written directions
received pursuant to Section 2.6(a) to the extent such written directions are
known by the Trustee to be in conflict with any provisions of law or if the
Trustee shall have received from independent counsel an unqualified opinion to
the effect that following such written directions would result in a breach of a
provision or covenant contained in the Indenture providing for the securing of
the indebtedness outstanding thereunder equally and ratably with other
indebtedness or obligations of the Company or any of its subsidiaries.

                  (c)      Nothing in this Section 2.6 shall impair the right of
the Trustee in its discretion to take or omit to take any action deemed proper
by the Trustee and which action or omission is not inconsistent with the
direction of the Holders entitled to direct the Trustee pursuant to this Section
2.6; provided, however, that the Trustee shall not be under any obligation to
take any action that is discretionary with the Trustee under the provisions
hereof or under any Security Document.

                  2.7      Remedies Not Exclusive.

                  (a)      No remedy conferred upon or reserved to the Trustee
herein or in any Security Document is intended to be exclusive of any other
remedy or remedies, but every such remedy shall be cumulative and shall be in
addition to every other remedy conferred herein or in any Security Document or
now or hereafter existing at law or in equity or by statute.

                  (b)      No delay or omission of the Trustee to exercise any
right, remedy or power accruing upon any Actionable Default shall impair any
such right, remedy or power or shall be construed to be a waiver of any such
Actionable Default or an acquiescence therein; and every right, power and remedy
given by this Agreement or any Security Document to the Trustee may be exercised
from time to time and as often as may be deemed expedient by the Trustee.

                  (c)      In case the Trustee shall have proceeded to enforce
any right, remedy or power under this Agreement or any Security Document and the
proceeding for the enforcement thereof shall have been discontinued or abandoned
for any reason or shall have been determined adversely to the Trustee, then and
in every such case the Trustors, the Trustee and the Holders shall, subject to
any determination in such proceeding, severally and respectively be restored to
their former positions and rights hereunder and under such Security Document
with respect to the Trust Estate and in all other respects, and thereafter all
rights, remedies and powers of the Trustee shall continue as though no such
proceeding had been taken.

                  (d)      All rights of action and rights to assert claims upon
or under this Agreement and the Security Documents may be enforced by the
Trustee without the possession of any Debt Instrument or the production thereof
in any trial or other proceeding relative thereto, and any such suit or
proceeding instituted by the Trustee shall be brought in its name as Trustee and
any recovery of judgment shall be held as part of the Trust Estate.

                  2.8      Waiver of Certain Rights.

                  The Trustors, to the extent they may lawfully do so, on behalf
of themselves and all who may claim through or under them, including, without
limitation, any and all subsequent creditors, vendees, assignees and lienors,
expressly waive and release any, every and all rights to


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demand or to have any marshaling of the Trust Estate upon any sale, whether made
under any power of sale herein granted or pursuant to judicial proceedings or
upon any foreclosure or any enforcement of this Agreement and consents and
agrees that all the Trust Estate may at any such sale be offered and sold as an
entirety.

                  2.9      Limitation on Trustee's Duties in Respect of
Collateral.

                  Beyond its duties set forth in this Agreement as to the
custody thereof and the accounting to the Trustors and the Holders for moneys
received by it hereunder, the Trustee shall not have any duty to the Trustors
and the Holders as to any Collateral in its possession or control or in the
possession or control of any agent or nominee of it or any income thereon or as
to the preservation of rights against prior parties or any other rights
pertaining thereto. To the extent, however, that the Trustee or any agent or
nominee thereof maintains possession or control of any of the Collateral, the
Trustee shall, and shall instruct such agent or nominee to, grant the Trustors
access to such Collateral that the Trustors require for the normal conduct of
their business, consistent with their current practice so long as the Trustee
shall not have received a Notice of Actionable Default.

                  2.10     Limitation by Law.

                  All rights, remedies and powers provided by this Section 2 may
be exercised only to the extent that the exercise thereof does not violate any
applicable provision of law in the premises, and all the provisions of this
Section 2 are intended to be subject to all applicable mandatory provisions of
law that may be controlling in the premises and to be limited to the extent
necessary so that they will not render this Agreement invalid, unenforceable in
whole or in part or not entitled to be recorded, registered, or filed under the
provisions of any applicable law.

                  2.11     Absolute Rights of Holders; Equal and Ratable
Security.

                  Notwithstanding any other provision of this Agreement or any
provision of any Security Document, the right of each Holder, which is absolute
and unconditional, to receive payments of the Secured Debt held by such Holder
on or after the due date thereof as therein expressed, to seek adequate
protection in respect of its interest in this Agreement and the Collateral, to
institute suit for the enforcement of such payment on or after such due date, or
to assert its position and views as a secured creditor in a Bankruptcy
Proceeding, or the obligation of the Trustors, which is also absolute and
unconditional, to pay the Secured Debt to the Holders at the time and place
expressed therein shall not be impaired or affected without the consent of such
Holder.

                  This Agreement and the Security Documents are intended to
secure the unpaid principal of and accrued interest and premium, if any, on the
Senior Public Notes equally and ratably with all indebtedness and other
obligations of the Trustors under the Credit Agreement, this Agreement and the
Security Documents to the extent required by the Indenture, and shall be
construed and enforced to give effect to such intention.


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                                   SECTION 3

       Trust Account, L/C Cash Collateral Account, Application Of Moneys.

                  3.1      The Trust Account; L/C Cash Collateral Account.

                  (a)      On the date hereof there shall be established and, at
all times thereafter until the trusts created by this Agreement shall have
terminated, there shall be maintained, with the Trustee an account that shall be
entitled the "Caremark Rx, Inc. Trust Account" (the "TRUST ACCOUNT"). The Trust
Account shall be established and maintained by the Trustee at the office of its
corporate trust services division. All moneys that are received by the Trustee
after the occurrence of an Actionable Default in respect of the Collateral shall
be deposited in the Trust Account and thereafter shall be held and applied by
the Trustee in accordance with the terms of this Agreement. To the extent
necessary, appropriate or desirable, the Trustee from time to time may
establish sub-accounts as part of the Trust Account for the purpose of better
identifying and maintaining proceeds of Collateral, all of which sub-accounts
shall be treated as and be deemed equivalent to, the "Trust Account" for all
purposes hereof.

                  (b)      On the date hereof there shall be established and, at
all times thereafter until the trusts created by this Agreement shall have
terminated, there shall be maintained, with the Trustee an account that shall be
entitled the "Caremark Rx, Inc. L/C Cash Collateral Account" (the "L/C CASH
COLLATERAL ACCOUNT"). The L/C Cash Collateral Account shall be established and
maintained by the Trustee at the office of its corporate services division. All
moneys that are received by the Trustee pursuant to the Credit Agreement to be
deposited in the L/C Cash Collateral Account shall be held and applied by the
Trustee in accordance with the terms of this Agreement.

                  3.2      Control of Trust Account and L/C Cash Collateral
Account.

                  All right, title and interest in and to the Trust Account and
L/C Cash Collateral Account shall vest in the Trustee, and funds on deposit in
the Trust Account and L/C Cash Collateral Account shall constitute part of the
Trust Estate. The Trust Account and L/C Cash Collateral Account shall be subject
to the exclusive dominion and control of the Trustee.

                  3.3      Investment of Funds Deposited in Trust Account and
L/C Cash Collateral Account.

                  The Trustee pursuant to the written direction of the
Administrative Agent shall invest and reinvest moneys on deposit in the Trust
Account and L/C Cash Collateral Account at any time in money market funds
investing in:

                           (i)      marketable obligations of the United States
         having a maturity of not more than one year from the date of
         acquisition;

                           (ii)     marketable obligations directly and fully
         guaranteed by the United States having a maturity of not more than one
         year from the date of acquisition; or


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                           (iii)    repurchase obligations with a term of not
         more than thirty days for underlying securities of the types described
         in clauses (i) and (ii) entered into with either (A) the Trustee or (B)
         any nationally recognized investment banking firm.

All such investments and the interest and income received thereon and therefrom
and the net proceeds realized on the sale thereof shall be held in the Trust
Account and L/C Cash Collateral Account, as applicable, as part of the Trust
Estate.

                  3.4      Application of Moneys in Trust Account and L/C Cash
Collateral Account.

                  (a)      Trust Account: Subject to Section 3.5, all moneys
held by the Trustee in the Trust Account shall, to the extent available for
distribution, be distributed (or deposited in a separate account for the benefit
of the Public Trustee pursuant to Section 3.5) by the Trustee as follows:

                           FIRST: To the Trustee in an amount equal to the
         Trustee's Fees that are unpaid as of the relevant Distribution Date and
         to any Holder that has theretofore advanced or paid any such Trustee's
         Fees in an amount equal to the amount thereof so advanced or paid by
         such Holder prior to such Distribution Date;

                           SECOND: To the Holders in an amount equal to the
         aggregate unpaid principal amounts due under or in respect of and
         unpaid interest on the Secured Debt in the case of a holder of the Bank
         Debt and a holder of the Senior Public Notes, and all unpaid
         obligations under the Hedge Agreements, in the case of a Hedge Bank, in
         each case whether or not then due and payable, and, in case such moneys
         shall be insufficient to pay in full such amounts, then to the payment
         thereof ratably (without priority of any one over any other) to each
         Holder in the same proportion that the aggregate unpaid principal
         amount of and unpaid interest on the Secured Debt under the Credit
         Agreement or the Senior Public Notes in the case of a holder of the
         Bank Debt or a holder of the Senior Public Notes or all obligations
         under its Hedge Agreement on a mark to market calculation as of the
         Distribution Date in the case of a Hedge Bank bears to the aggregate
         unpaid principal amount of and unpaid interest on the Secured Debt
         under the Credit Agreement and all Senior Public Notes and the unpaid
         obligations under all Hedge Agreements based on such calculation on the
         relevant Distribution Date; and

                           THIRD: To the Holders in an amount equal to all other
         unpaid Secured Debt whether or not due and payable, and, in case such
         moneys shall be insufficient to pay in full such amount, then to the
         payment thereof ratably (without priority of any one over any other) to
         each Holder in the same proportion that such other unpaid Secured Debt
         of such Holder bears to all such other unpaid Secured Debt of all
         Holders on the relevant Distribution Date; and

                           FOURTH: Any surplus then remaining shall be paid to
         the respective Trustor, its successors or assigns, or to whomsoever may
         be lawfully entitled to receive the same, or as a court of competent
         jurisdiction may direct.


                                       10
<PAGE>   15

                  (b)      L/C Cash Collateral Account: Subject to Section 3.5,
all moneys held by the Trustee in the L/C Cash Collateral Account shall, to the
extent available for distribution, during the continuance of an Actionable Event
of Default, be distributed (or deposited in a separate account for the benefit
of the Public Trustee pursuant to Section 3.5) by the Trustee as follows:

                           FIRST: To the Trustee in an amount equal to the
         Trustee's Fees that are unpaid as of the relevant Distribution Date and
         to any Holder that has theretofore advanced or paid any such Trustee's
         Fees in an amount equal to the amount thereof so advanced or paid by
         such Holder prior to such Distribution Date;

                           SECOND: To the Holders in an amount equal to the
         aggregate unpaid principal amounts due under or in respect of and
         unpaid interest on the Secured Debt whether or not then due and
         payable, and, in case such moneys shall be insufficient to pay in full
         such amounts, then to the payment thereof ratably (without priority of
         any one over any other) to each Holder in the same proportion that the
         aggregate unpaid principal amount of an unpaid interest on the Secured
         Debt under the Secured Credit Agreement or the Senior Public Notes in
         the case of a holder of the Bank Debt held by such Holder or a holder
         of the Senior Public Notes or all obligations under its Hedge Agreement
         on a mark to market calculation as of the Distribution Date in the case
         of each Hedge Bank bears to the aggregate unpaid principal amount of
         and unpaid interest on the Secured Debt under the Credit Agreement and
         all Senior Public Notes and the unpaid interest amounts under all Hedge
         Agreements based on the Secured Debt held by all Holders such
         calculation on the relevant Distribution Date; and

                           THIRD: To the Holders in an amount equal to all other
         unpaid Secured Debt whether or not due and payable, and, in case such
         moneys shall be insufficient to pay in full such amount, then to the
         payment thereof ratably (without priority of any one over any other) to
         each Holder in the same proportion that such other unpaid Secured Debt
         of such Holder bears to all such other unpaid Secured Debt of all
         Holders on the relevant Distribution Date; and

                           FOURTH: Any surplus then remaining shall be paid to
         the respective Trustor, its successors or assigns, or to whomsoever may
         be lawfully entitled to receive the same, or as a court of competent
         jurisdiction may direct.

Except during the continuance of an Actionable Event of Default, the Trustee,
upon the request of the Administrative Agent from time to time, shall release to
the Administrative Agent all or such portion of the amounts in the L/C Cash
Collateral Account as specified in such request and shall release to the Company
all amount in the L/C Cash Collateral Account in respect of the undrawn portion
of letters of credit which have been cancelled or otherwise have been
terminated, as specified in such request.

                  (c)      The term "unpaid" as used in this Section 3.4 shall
mean all amounts of Trustee's Fees and the Secured Debt outstanding as of a
Distribution Date as to which prior distributions (whether actually distributed
or set aside pursuant to Section 3.5) have not been made, or if made, have
subsequently been recovered from the recipient thereof.


                                       11
<PAGE>   16

                  3.5      Application of Moneys Distributable to Holders of
Senior Public Notes.

                  If at any time any moneys collected or received by the Trustee
pursuant to this Agreement or any Security Document are distributable pursuant
to Section 3.4(a) or (b) to the Public Trustee, and if the Public Trustee shall
notify the Trustee that no provision is made under the Indenture (i) for the
application by the Public Trustee of such amounts so distributable (whether by
virtue of the Secured Debt issued under the Indenture not having become due and
payable or otherwise) or (ii) for the receipt and the holding by the Public
Trustee of such amounts pending the application thereof, then the Trustee shall
invest such amounts in obligations of the kinds referred to in Section 3.3, and
shall hold all such amounts so distributable, and all such investments and the
proceeds thereof, in trust solely for the Public Trustee and for no other
purpose until such time as the Public Trustee shall request the delivery thereof
by the Trustee to the Public Trustee for application by it pursuant to the
Indenture.

                                    SECTION 4

                          Agreements With The Trustee.

                  4.1      Delivery of Debt Instruments.

                  Within 10 days after the date hereof, the Company will deliver
to the Trustee a true and complete copy of each of the Debt Instruments and any
Hedge Agreement as in effect on the date hereof. The Company agrees that,
promptly upon the execution thereof, the Company will deliver to the Trustee a
true and complete copy of any and all Hedge Agreements and any and all
amendments, modifications or supplements entered into subsequent to the date
hereof to any Debt Instrument or Hedge Agreements entered into subsequent to the
date hereof.

                  4.2      Information as to Holders.

                  The Company agrees that it shall deliver to the Trustee from
time to time upon request of the Trustee, a list setting forth, by each Debt
Instrument and Hedge Agreement:

                           (i)      the aggregate principal amount outstanding
         thereunder, (ii) the interest rates then in effect thereunder; and

                           (ii)     to the extent known to the Company, the
         names of the Holders of the Secured Debt outstanding thereunder and the
         unpaid principal amount thereof owing to each Private Lender, the
         Public Trustee and each Hedge Bank. The Company will furnish to the
         Trustee within 30 days after the date hereof a list setting forth the
         name and address of each party to whom notices must be sent under the
         Debt Instruments and Hedge Agreements.

                  4.3      Compensation and Expenses.

                  The Trustors, jointly and severally, agree to pay to the
Trustee, from time to time upon demand:


                                       12
<PAGE>   17

                           (i)      reasonable compensation (which shall not be
         limited by any provision of law in regard to compensation of a trustee
         of an express trust) for their services hereunder and under the
         Security Documents and for administering the Trust Estate; and

                           (ii)     all of the fees, costs and expenses of the
         Trustee (including, without limitation, the reasonable fees and
         disbursements of their counsel and such special counsel as the Trustee
         elect to retain) (A) arising in connection with the preparation,
         execution, delivery, modification and termination of this Agreement and
         each Security Document or the enforcement of any of the provisions
         hereof or thereof or (B) incurred or required to be advanced in
         connection with the administration of the Trust Estate, the sale or
         other disposition of Collateral pursuant to any Security Document and
         the preservation, protection or defense of the Trustee's rights under
         this Agreement and in and to the Collateral and the Trust Estate.

                  4.4      Stamp and Other Similar Taxes.

                  The Trustors, jointly and severally, agree to indemnify and
hold harmless the Trustee and each Holder from any present or future claim for
liability for any stamp or other similar tax and any penalties or interest with
respect thereto that may be assessed, levied or collected by any jurisdiction in
connection with this Agreement, any Security Document, the Trust Estate or any
Collateral. The obligations of the Trustors under this Section 4.4 shall survive
the termination of the other provisions of this Agreement.

                  4.5      Filing Fees, Excise Taxes, etc.

                  The Trustors, jointly and severally, agree to pay or to
reimburse the Trustee for any and all amounts in respect of all search, filing,
recording and registration fees, taxes, excise taxes and other similar imposts
that may be payable or determined to be payable in respect of the execution,
delivery, performance and enforcement of this Agreement and each Security
Document. The obligations of the Trustors under this Section 4.5 shall survive
the termination of the other provisions of this Agreement.

                  4.6      Indemnification.

                  The Trustors, jointly and severally, agree to pay, indemnify,
and hold the Trustee and each of its agents harmless from and against any and
all liabilities, obligations, losses, damages, penalties, actions, judgments,
suits, costs, expenses or disbursements of any kind or nature whatsoever with
respect to the execution, delivery, enforcement, performance and administration
of this Agreement and the Security Documents (including, but not limited to,
actions by the Trustee to enforce its rights with respect to the Collateral),
unless arising from the gross negligence or willful misconduct (in either case,
as determined by a final judgment of a court of competent jurisdiction) of the
Trustee or such of the agents as are seeking indemnification. The foregoing
indemnities in this Section 4.6 shall survive the resignation or removal of the
Trustee or the termination of this Agreement.

                  4.7      Further Assurances; Notation on Financial Statements.


                                       13
<PAGE>   18

                  (a)      At any time and from time to time, upon the written
request of the Trustee, and, at the sole expense of the Trustors, the Trustors
will promptly execute and deliver any and all such further instruments and
documents and take such further action as the Trustee reasonably deems necessary
or desirable in obtaining the full benefits of this Agreement and the Security
Documents and of the rights and powers herein and therein granted. To the extent
required by law, the Trustors shall, in all of their financial statements,
indicate by footnote or otherwise that the Secured Debt is secured pursuant to
this Agreement and the Security Documents.

                  (b)      Pursuant to the Credit Agreement, from time to time
additional subsidiaries of the Company are required to become parties to the
Guarantee and to the Security Agreement. In connection with a subsidiary
becoming party to the Security Agreement, such subsidiary (an "ADDITIONAL
TRUSTOR") shall execute a Supplement to Trust Agreement in the form of Exhibit A
hereto and upon such execution shall become a Trustor hereunder with all
applicable rights and responsibilities.

                                   SECTION 5

                                  The Trustee.

                  5.1      Acceptance of Trust.

                  The Trustee, for itself and its successors, hereby accepts the
trusts created by this Agreement upon the terms and conditions hereof, including
those contained in this Section 5.

                  5.2      Exculpatory Provisions.

                  (a)      The Trustee shall not be responsible in any manner
whatsoever for the correctness of any recitals, statements, representations or
warranties' contained herein or in any Security Document, all of which are made
solely by the Trustors. The Trustee makes no representations as to the value or
condition of the Trust Estate or any part thereof, or as to the title of the
Trustors thereto or as to the security afforded by any Security Document or this
Agreement, or as to the validity, execution (except its own execution),
enforceability, legality or sufficiency of this Agreement, any Security Document
or the Secured Debt secured hereby and thereby, and the Trustee shall incur no
liability or responsibility in respect of any such matters. The Trustee shall
not be responsible for insuring the Trust Estate or for the payment of taxes,
charges, assessments or liens upon the Trust Estate or otherwise as to the
maintenance of the Trust Estate, except that in the event the Trustee enters
into possession of a part or all of the Trust Estate, the Trustee shall preserve
the part in its possession.

                  (b)      The Trustee shall not be required to ascertain or
inquire as to the performance by the Trustors of any of the covenants or
agreements contained herein, in any Security Document or in any Debt Instrument.
Whenever it is necessary, or in the opinion of the Trustee advisable, for the
Trustee to ascertain the amount of Secured Debt then held by a Holder, the
Trustee may rely on a certificate of such Holder or its representative as to
such amount, and if any such Holder or representative shall not give such
information to the Trustee, such Holder shall not be entitled to receive
distributions hereunder (in which case such distributions shall be held in trust
for such Holder) until it has given such information to the Trustee.


                                       14
<PAGE>   19

                  (c)      The Trustee shall not be personally liable for any
action taken or omitted to be taken by them in accordance with this Agreement or
any Security Document except for its own gross negligence or willful misconduct.

                  (d)      Aside from filing continuation statements with
respect to the uniform commercial code financing statements filed by the
Trustors on or about the date hereof naming the Trustee as secured party, the
Trustee shall have no responsibility for the preparation, filing or recording of
any instrument, document or financing statement or for the maintenance of any
security interest intended to be perfected thereby.

                  5.3      Delegation of Duties.

                  The Trustee may execute any of the trusts or powers hereof and
perform any duty hereunder either directly or by or through agents or
attorneys-in-fact, which may include officers and employees of the Trustors. The
Trustee shall be entitled to advice of counsel concerning all matters pertaining
to such trusts, powers and duties. The Trustee shall not be responsible for the
negligence or misconduct of any agents or attorneys-in-fact selected by it
without gross negligence or willful misconduct.

                  5.4      Reliance by Trustee.

                  (a)      Whenever in the administration of the trusts of this
Agreement the Trustee shall deem it necessary or desirable that a matter be
proved or established in connection with the taking, suffering or omitting any
action hereunder by the Trustee, such matter (unless other evidence in respect
thereof be herein specifically prescribed) may be deemed to be conclusively
provided or established by a certificate of a Responsible Officer of any Trustor
delivered to the Trustee, and such certificate shall be full warranty to the
Trustee for any action taken, suffered or omitted in reliance thereon, subject,
however, to the provisions of Section 5.5.

                  (b)      The Trustee may consult with counsel, and any opinion
of such counsel who is not employees of the Trustee shall be full and complete
authorization and protection in respect of any action taken or suffered by it
hereunder in accordance therewith. The Trustee shall have the right at any time
to seek instructions concerning the administration of the Trust Estate from any
court of competent jurisdiction.

                  (c)      The Trustee may rely, and shall be fully protected in
acting, upon any resolution, statement, certificate, instrument, opinion,
report, notice, request, consent, order, bond or other paper or document that it
has no reason to believe to be other than genuine and to have been signed or
presented by the proper party or parties or, in the case of cables, telecopies
and telexes, to have been sent by the proper party or parties. In the absence of
its gross negligence or willful misconduct, the Trustee may conclusively rely,
as to the truth of the statements and the correctness of the opinions expressed
therein, upon any certificates or opinions furnished to the Trustee and
conforming to the requirements of this Agreement or any Security Document.

                  (d)      The Trustee shall not be under any obligation to
exercise any of the rights or powers vested in the Trustee by this Agreement at
the request or direction of the Majority Holders pursuant to this Agreement or
any Security Document unless the Trustee shall have been


                                       15
<PAGE>   20

provided adequate security and indemnity against the costs, expenses and
liabilities that may be incurred by it in compliance with such request or
direction, including such reasonable advances as may be requested by the
Trustee.

                  5.5      Limitations on Duties of Trustee.

                  (a)      Prior to the occurrence of an Actionable Default, the
Trustee shall be obliged to perform such duties and only such duties as are
specifically set forth in this Agreement or in any Security Document, and no
implied covenants or obligations shall be read into this Agreement or any
Security Document against the Trustee. The Trustee shall, during the existence
of any Actionable Default, exercise the rights and powers vested in it by this
Agreement or by any Security Document, and the Trustee shall not be liable with
respect to any action taken or omitted by it in accordance with the direction of
the Holders pursuant to Section 2.6.

                  (b)      Except as herein otherwise expressly provided, the
Trustee shall not be under any obligation to take any action that is
discretionary with the Trustee under the provisions hereof or under any Security
Document except upon the written request of the Holders pursuant to Section 2.6.
The Trustee shall make available for inspection and copying by the
Administrative Agent and the Public Trustee each certificate or other paper
furnished to the Trustee by the Company under or in respect of this Agreement,
any Security Document or any of the Trust Estate.

                  5.6      Moneys to be Held in Trust.

                  All moneys received by the Trustee under or pursuant to any
provision of this Agreement or any Security Document shall be held in trust for
the purposes for which they were paid or are held.

                  5.7      Resignation and Removal of the Trustee.

                  (a)      The Trustee may at any time, by giving 30 days' prior
written notice to the Company and the Holders, resign and be discharged of the
responsibilities hereby created, such resignation to become effective upon the
earlier of: (i) 30 days from the date of such notice; and (ii) (the appointment
of a successor trustee or trustees by the Company, the acceptance of such
appointment by such successor trustee or trustees, and the approval of such
successor trustee or trustees by the Majority Holders. The Trustee may be
removed at any time and a successor trustee or trustees appointed by the
affirmative vote of the Majority Holders; provided that the Trustee shall be
entitled to its fees and expenses to the date of removal. If no successor
trustee or trustees shall be appointed and approved within 30 days from the date
of the giving of the aforesaid notice of resignation or within 30 days from the
date of such removal, the Trustee (notwithstanding the termination of all of its
duties and obligations hereunder by reason of such resignation) shall, or any
Holder may, apply to any court of competent jurisdiction to appoint a successor
trustee or trustees (which may be an individual or individuals) to act until
such time, if any, as a successor trustee or trustees shall have been appointed
as above provided. Any successor trustee or trustees so appointed by such court
shall immediately and without further act


                                       16
<PAGE>   21

be superseded by any successor trustee or trustees approved by the Majority
Holders as above provided.

                  (b)      If at any time the Trustee shall resign or be removed
or otherwise become incapable of acting, or if at any time, a vacancy shall
occur in the office of the Trustee for any other cause, a successor trustee or
trustees may be appointed by the Majority Holders, and the powers, duties,
authority and title of the predecessor trustee or trustees terminated and
canceled without procuring the resignation of such predecessor trustee or
trustees, and without any other formality (except as may be required by
applicable law) than appointment and designation of a successor trustee or
trustees in writing, duly acknowledged, delivered to the predecessor trustee or
trustees and the Company, and filed for record in each public office, if any, in
which this Agreement is required to be filed.

                  (c)      The appointment and designation referred to in
Section 5.7(b) shall, after any required filing, be full evidence of the right
and authority to make the same and of all the facts therein recited, and this
Agreement shall vest in such successor trustee or trustees, without any further
act, deed or conveyance, all of the estate and title of its predecessor, and
upon such filing for record the successor trustee or trustees shall become fully
vested with all the estates, properties, rights, powers, trusts, duties,
authority and title of its predecessor; but such predecessor shall,
nevertheless, on the written request of the Majority Holders, the Company or the
successor trustee or trustees, execute and deliver an instrument transferring to
such successor or successors all the estates, properties, rights, powers,
trusts, duties, authority and title of such predecessor or predecessors
hereunder and shall deliver all securities and moneys held by it to such
successor trustee or trustees. Should any deed, conveyance or other instrument
in writing from any Trustor be required by any successor trustee or trustees for
more fully and certainly vesting in such successor trustee or trustees the
estates, properties, rights, powers, trusts, duties, authority and title vested
or intended to be vested in the predecessor trustee or trustees, any and all
such deeds, conveyances and other instruments in writing shall, on request of
such successor trustee or trustees, be executed, acknowledged and delivered by
such Trustor.

                  (d)      Any required filing for record of the instrument
appointing a successor trustee or trustees as hereinabove provided shall be at
the expense of the Trustors. The resignation of any trustee or trustees and the
instrument or instruments removing any trustee or trustees, together with all
other instruments, deeds and conveyances provided for in this Section 5 shall,
if permitted by law, be forthwith recorded, registered and filed by and at the
expense of the Trustors, wherever this Agreement is recorded, registered and
filed.

                  5.8      Status of Successors to the Trustee.

                  Except as permitted by Section 5.7, every successor to the
Trustee appointed pursuant to Section 5.7 shall be a bank or trust company in
good standing and having power so to act, incorporated under the laws of the
United States or any State thereof or the District of Columbia, and having its
principal corporate trust office within the 48 contiguous States, and shall also
have capital, surplus and undivided profits of not less than $100,000,000, if
there be such an institution with such capital, surplus and undivided profits
willing, qualified and able to accept the trust upon reasonable or customary
terms.


                                       17
<PAGE>   22

                  5.9      Merger of the Trustee.

                  Any corporation into which the Trustee may be merged, or with
which it may be consolidated, or any corporation resulting from any merger or
consolidation to which the Trustee shall be a party, shall be Trustee under this
Agreement without the execution or filing of any paper or any further act on the
part of the parties hereto.

                  5.10     Co-Trustee, Separate Trustee.

                  (a)      If at any time or times it shall be necessary or
prudent in order to conform to any law of any jurisdiction in which any of the
Collateral shall be located, or the Trustee shall be advised by counsel,
satisfactory to it, that it is so necessary or prudent in the interest of the
Holders, or the Majority Holders shall in writing so request the Trustee and the
Trustors, or the Trustee shall deem it desirable for its own protection in the
performance of its duties hereunder, the Trustee and the Trustors shall execute
and deliver all instruments and agreements necessary or proper to constitute
another bank or trust company, or one or more persons approved by the Trustee
and the Trustors, either to act as co-trustee or co-trustees of all or any of
the Collateral, jointly with the Trustee originally named herein or any
successor or successors, or to act as separate trustee or trustees of any such
property. In the event the Trustors shall not have joined in the execution of
such instruments and agreements within 30 days after the receipt of a written
request from the Trustee so to do, or in case an Actionable Default shall have
occurred and be continuing, the Trustee may act under the foregoing provisions
of this Section 5.10 without the concurrence of the Trustors, and the Trustors
hereby appoint the Trustee as its agent and attorney to act for it under the
foregoing provisions of this Section 5.10 in either of such contingencies.

                  (b)      Every separate trustee and every co-trustee, other
than any trustee that may be appointed as successor to the Trustee, shall, to
the extent permitted by law, be appointed and act and be such, subject to the
following provisions and conditions, namely:

                           (i)      all rights, powers, duties and obligations
         conferred upon the Trustee in respect of the custody, control and
         management of moneys, papers or securities shall be exercised solely by
         the Trustee, or its successors as Trustee hereunder;

                           (ii)     all rights, powers, duties and obligations
         conferred or imposed upon the Trustee hereunder shall be conferred or
         imposed and exercised or performed by the Trustee and such separate
         trustee or separate trustees or co-trustee or co-trustees, jointly, as
         shall be provided in the instrument appointing such separate trustee or
         separate trustees or co-trustee or co-trustees, except to the extent
         that under any law of any jurisdiction in which any particular act or
         acts are to be performed the Trustee shall be incompetent or
         unqualified to perform such act or acts, in which event such rights,
         powers, duties and obligations shall be exercised and performed by such
         separate trustee or separate trustees or co-trustee or co-trustees;

                           (iii)    no power given hereby to, or that it is
         provided hereby may be exercised by, any such co-trustee or co-trustees
         or separate trustee or separate trustees, shall be exercised hereunder
         by such co-trustee or co-trustees or separate trustee or


                                       18
<PAGE>   23

         separate trustees, except jointly with, or with the consent in writing
         of, the Trustee, anything herein contained to the contrary
         notwithstanding;

                           (iv)     no trustee hereunder shall be personally
         liable by reason of any act or omission of any other trustee hereunder;
         and

                           (v)      the Trustors and the Trustee, at any time by
         an instrument in writing, executed by them, may accept the resignation
         of or remove any such separate trustee or co-trustee, and in that case,
         by an instrument in writing executed by the Trustors and the Trustee
         jointly, may appoint a successor to such separate trustee or
         co-trustee, as the case may be, anything herein contained to the
         contrary notwithstanding. In the event that the Trustors shall not have
         joined in the execution of any such instrument within ten days after
         the receipt of a written request from the Trustee so to do, or in case
         an Actionable Default shall have occurred and be continuing, the
         Trustee shall have the power to accept the resignation of or remove any
         such separate trustee or co-trustee and to appoint a successor without
         the concurrence of the Trustors, the Trustors hereby appointing the
         Trustee its agent and attorney to act for it in such connection in
         either of such contingencies. In the event that the Trustee shall have
         appointed a separate trustee or separate trustees or co-trustee or
         co-trustees as above provided, it may at any time, by an instrument in
         writing, accept the resignation of or remove any such separate trustee
         or co-trustee, the successor to any such separate trustee or co-trustee
         to be appointed by the Trustors and the Trustee, or by the Trustee
         alone, as provided in this Section 5.10.

                                    SECTION 6

                             Release of Collateral.

                  6.1      Conditions to Release; Release Procedure.

                  (a)      Subject to Section 6.1(b) and 6.1(c), the Collateral
shall be released on the earliest of the dates listed below:

                           (i)      the date on which the Trustee and the Public
         Trustee shall have received written notice from the Administrative
         Agent that (A) no Advances (as defined in the Credit Agreement) or any
         of the other Obligations (as defined in the Credit Agreement) of a Loan
         Party (as defined in the Credit Agreement) under or in respect of the
         Loan Documents (as defined in the Credit Agreement) shall remain
         unpaid, (B) no Letter of Credit (as defined in the Credit Agreement)
         shall remain outstanding and (C) no Lender Party (as defined in the
         Credit Agreement) shall have any Commitment (as defined in the Credit
         Agreement) under the Credit Agreement; or

                           (ii)     the date on which the Trustee shall have
         received written directions from the Administrative Agent directing the
         Trustee to release the Collateral (with a copy of such directions to be
         sent contemporaneously to the Public Trustee).


                                       19
<PAGE>   24

                  (b)      All of the Collateral shall not be released unless
and until all Trustees' Fees shall have been paid in full.

                  (c)      From time to time during the term of this Agreement,
portions of Collateral shall be released on the date on which the Trustee shall
have received written directions from the Administrative Agent directly the
Trustee to release such portion of the Collateral.

                  (d)      Upon the release of the Collateral, or any portion
thereof, all right, title and interest of the Trustee in, to and under the Trust
Estate in respect of the Collateral or portion thereof so released, and the
Security Documents in respect of such Collateral, shall terminate and shall
revert to the respective Trustors, their successors and assigns, and the estate,
right, title and interest of the Trustee therein shall thereupon cease,
determine and become void; and in such case, upon the written request of the
respective Trustors, their successors or assigns, and at the cost and expense of
the Trustors, their successors or assigns, the Trustee shall execute in respect
of the Collateral so released, a satisfaction of the Security Documents and such
instruments as are necessary or desirable to terminate and remove of record any
documents constituting public notice of the Security Documents and the security
interests and assignments granted thereunder and shall assign and transfer, or
cause to be assigned and transferred, and shall deliver or cause to be delivered
to the Trustors, in respect of the Collateral so released, all property,
including all moneys, instruments and securities, of the Trustors then held by
the Trustee. The cancellation and satisfaction of the Security Documents shall
be without prejudice to the rights of the Trustee or any successor trustee to
charge and be reimbursed for any expenditures that it may thereafter incur in
connection therewith.

                                    SECTION 7

                                 Miscellaneous.

                  7.1      Amendments, Supplements and Waivers.

                  (a)      With the written consent of the Administrative Agent
and the Public Trustee, the Trustee and the Trustors may, from time to time,
enter into written agreements supplemental hereto for the purpose of adding to
or waiving any provision of this Agreement or any Security Document or changing
in any manner the rights of the Trustee, the Holders or the Trustors hereunder
or thereunder; provided, however, that no such supplemental agreement shall:

                           (i)      amend, modify or waive any provision of this
         Section 7.1 without the written consent of each Holder,

                           (ii)     reduce the percentage specified in the
         definition of Majority Holders without the written consent of all the
         Holders,

                           (iii)    amend, modify or waive any provision of
         Section 3.4, 3.5 or 6.1 or the definition of the term "Secured Debt"
         without the written consent of any Holder whose rights would be
         adversely affected thereby,


                                       20
<PAGE>   25

                           (iv)     amend, modify or waive any provision of
         Section 5 or alter the duties or obligations of the Trustee hereunder
         without the written consent of the Trustee.

Any such supplemental agreement shall be binding upon the Trustors, the Holders
and the Trustee and their respective successors. The Trustee shall not enter
into any such supplemental agreement unless it shall have received a certificate
of a Responsible Officer of the Trustors to the effect that such supplemental
agreement will not result in a breach of any provision or covenant contained in
the Indenture.

                  (b)      Without the consent of any Holders, the Trustee and
the Trustors, at any time and from time to time, may enter into additional
pledge or security agreements or one or more agreements supplemental hereto or
to any Security Document, in form satisfactory to the Trustee,

                           (i)      to add to the covenants of the Trustors, for
         the benefit of the Holders, or to surrender any right or power herein
         conferred upon the Trustors;

                           (ii)     to mortgage, pledge or grant a security
         interest in any property or assets that are required to be mortgaged or
         pledged, or in which a security interest is required to be granted, to
         the Trustee pursuant to any Debt Instrument or any Security Document;
         and

                           (iii)    to cure any ambiguity in, to correct or to
         supplement any provision herein or in any Security Document that may be
         defective or inconsistent with any other provision herein or therein,
         or to make any other provisions with respect to matters or questions
         arising hereunder or under any Security Document that shall not be
         inconsistent with any provision hereof or of any Security Document.

                  7.2      Notices.

                  All notices, requests, demands and other communications
provided for or permitted hereunder shall be in writing (including telecopy
communications) and shall be sent by mail, telecopier or hand delivery:

                  (a)      If to any Trustor, to it at the address of the
Company at: 3000 Galleria Tower, Suite 1000, Birmingham, Alabama 35244,
Telecopier No. (205) 733-9780 or at such other address as shall be designated by
it in a written notice to the Trustee.

                  (b)      If to the Trustee, to it at its address at: 135 South
LaSalle Street, Suite 1960, Chicago, Illinois 60603, Attention: Corporate Trust
Services Division, Telecopier No: (312) 904-2236 or at such other address as
shall be designated by it in a written notice to the Company.

                  (c)      If to the Public Trustee, to it at its address at 180
East Fifth Street--2nd Floor, St. Paul, Minnesota 55101, Attention: Mr. Timothy
J. Sandell, Telecopier No. (651) 244-5847, or at such other address as shall be
designated by it in writing to the Trustee.


                                       21
<PAGE>   26

                  (d)      If to the Administrative Agent, to it at its address
at Independence Center, 101 North Tryon Street, 15th Floor, Charlotte, North
Carolina 28255, Attention: Corporate Credit Services, Telecopier No. (704)
386-9923 or at such other address as shall be designated by it in writing to the
Trustee.

                  (e)      If to any of the Hedge Banks, to it at its address
set forth in the respective Hedge Agreement to which it is a party (a copy of
which Hedge Agreement shall have been provided to the Trustee).

                  (f)      Any notice given to any Holder shall also be given to
the Public Trustee and the Administrative Agent.

All such notices, requests, demands and communications shall be deemed to have
been duly given or made, when delivered by hand or five Business Days after
being deposited in the mail, postage prepaid, or when telecopied, receipt
acknowledged; provided, however, that any notice, request, demand or other
communication to the Trustee shall not be effective until received.

                  7.3      Headings.

                  Section, subsection and other headings used in this Agreement
are for convenience only and shall not affect the construction of this
Agreement.

                  7.4      Severability.

                  Any provision of this Agreement that is prohibited or
unenforceable in any jurisdiction shall not invalidate the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction shall
not invalidate or render unenforceable such provision in any other jurisdiction.

                  7.5      Treatment of Payee or Indorsee by Trustee.

                  (a)      The Trustee may treat the registered holder of any
registered note, and the payee or indorsee of any note or debenture that is not
registered, as the absolute owner thereof for all purposes hereunder and shall
not be affected by any notice to the contrary, whether such promissory note or
debenture shall be past due or not.

                  (b)      Any person, firm, corporation or other entity that
shall be designated as the duly authorized representative of one or more Holders
of Secured Debt to act as such in connection with any matters pertaining to this
Agreement or any Security Document or the Collateral shall present to the
Trustee such documents, including, without limitation, opinions of counsel, as
the Trustee may reasonably require, in order to demonstrate to the Trustee the
authority of such person, firm, corporation or other entity to act as the
representative of such Holders.

                  7.6      Dealings with the Trustors.

                  (a)      Upon any application or demand by any Trustor to the
Trustee to take or permit any action under any of the provisions of this
Agreement, such Trustor shall furnish to the


                                       22
<PAGE>   27

Trustee a certificate of a Responsible Officer stating that all conditions
precedent, if any, provided for in this Agreement relating to the proposed
action have been complied with, except that in the case of any such application
or demand as to which the furnishing of such documents is specifically required
by any provision of this Agreement relating to such particular application or
demand, no additional certificate or opinion need be furnished.

                  (b)      Any opinion of counsel may be based, insofar as it
relates to factual matters, upon a certificate of a Responsible Officer filed
with the Trustee.

                  7.7      Claims Against the Trustee.

                  Any claims or causes of action that the Administrative Agent,
the Private Lenders, the Public Trustee or any Trustor shall have against the
Trustee shall survive the termination of this Agreement and the release of the
Collateral hereunder.

                  7.8      Binding Effect.

                  This Agreement shall be binding upon and inure to the benefit
of each of the parties hereto, the Holders, and their respective successors and
assigns, and nothing herein or in any Security Document is intended or shall be
construed to give any other person any right, remedy or claim under, to or in
respect of this Agreement, any Security Document, the Collateral or the Trust
Estate.

                  7.9      Governing Law.

                  This Agreement shall be governed by, and construed and
interpreted in accordance with, the laws of the State of Illinois and any action
alleging any breach by the Trustee of its duties hereunder, whether by act or
omission or anticipatory, shall be prosecuted only in the courts of the State of
Illinois.


                                       23
<PAGE>   28

                  7.10     Counterparts.

                  This Agreement may be executed in separate counterparts, each
of which shall be an original and all of which taken together shall constitute
one and the same instrument.

                  IN WITNESS WHEREOF, the parties hereto have executed this
Agreement or caused this Agreement to be duly executed by their respective
officers thereunto duly authorized as of the day and year first above written.

                                        LASALLE BANK NATIONAL ASSOCIATION,
                                                 AS TRUSTEE


                                        By:  /s/ John W. Porter
                                           -------------------------------------
                                        Title:  Assistant VP
                                              ----------------------------------

                                        CAREMARK RX, INC.


                                        By: /s/ Peter J. Clemens
                                           -------------------------------------
                                                Peter J. Clemens
                                        Title:  SVP & Treasurer

                                        CAREMARK INTERNATIONAL INC.


                                        By: /s/ Peter J. Clemens
                                           -------------------------------------
                                                Peter J. Clemens
                                        Title:  VP

                                        CAREMARK INC.

                                        By: /s/ Peter J. Clemens
                                           -------------------------------------
                                                Peter J. Clemens
                                        Title:  VP


                                       24