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                                                                   EXHIBIT 10.18

                                    AMENDMENT
                                       TO
                AMENDED AND RESTATED INCENTIVE COMPENSATION PLAN
                           EFFECTIVE NOVEMBER 15, 2000


         The Caremark Rx, Inc. Amended and Restated Incentive Compensation Plan
(the "Plan") is hereby amended as follows:

         1.       Amendment Regarding Transferability of Nonqualified Stock
Options. Section 7.3(b)(2) of the Plan is hereby amended by deleting Section
7.3(b)(2) in its entirety and substituting the following new Section 7.3(b)(2)
therefor:

                  (b) Nonqualified Stock Options. No nonqualified stock option
         granted under the Incentive Compensation Plan may be sold, transferred,
         pledged, assigned or otherwise alienated or hypothecated, other than by
         will or by the laws of descent and distribution. Notwithstanding the
         foregoing, to the extent not prohibited by any statute, rule or
         regulation applicable to the Incentive Compensation Plan, the
         nonqualified stock options, or the registration with the Securities and
         Exchange Commission of the Shares to be issued upon exercise of the
         nonqualified stock options, the Committee may, in its discretion,
         authorize all or a portion of nonqualified stock options granted to a
         Participant to be on terms which permit transfer by such Participant to
         (i) the spouse, children or grandchildren of the Participant
         ("Immediate Family Members"), (ii) a trust or trusts for the exclusive
         benefit of such Immediate Family Members, or (iii) a partnership in
         which such Immediate Family Members are the only partners, provided
         that (A) the Award Agreement pursuant to which such nonqualified stock
         options are granted must be approved by the Committee, and must
         expressly provide for transferability in a manner consistent with this
         Section, and (B) subsequent transfers of transferred nonqualified stock
         options shall be prohibited except those by will or the laws of descent
         and distribution. Following transfer, any such nonqualified stock
         options shall continue to be subject to the same terms and conditions
         as were applicable immediately prior to transfer, provided that for
         purposes of this Incentive Compensation Plan, the term "Participant"
         shall be deemed to refer to the transferee. The events of termination
         of employment shall continue to be applied with respect to the original
         Participant, following which the nonqualified stock options shall be
         exercisable by the transferee only to the extent, and for the periods
         specified in Section 7.4. Notwithstanding the foregoing, should the
         Committee provide that nonqualified stock options granted be
         transferable, the Company by such action incurs no obligation to notify
         or otherwise provide notice to a transferee of early termination of the
         nonqualified stock option. In the event of a transfer, as set forth
         above, the original Participant is and will remain subject to and
         responsible for any applicable withholding taxes upon the exercise of
         such nonqualified stock options.

         2.       Effective Date. The effective date of this Amendment shall be
November 15, 2000.


         3.       Miscellaneous.

                  (a) Capitalized terms not otherwise defined herein shall have
         the meanings given them in the Plan.

                  (b) Except as specifically amended hereby, the Plan shall
         remain in full force and effect.



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         IN WITNESS WHEREOF, the Company has caused this Amendment to the
Caremark Rx, Inc. Amended and Restated Incentive Compensation Plan to be
executed as of the Effective Date.

                                    CAREMARK RX, INC.

                                    -------------------------------------------

                                    Sara J. Finley, Corporate Secretary



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