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                                                                   EXHIBIT 10.25


                                SECOND AMENDMENT
                                     TO THE
                   CAREMARK RX, INC. 1994 STOCK INCENTIVE PLAN
                         (FORMERLY THE MEDPARTNERS, INC.
                           1994 STOCK INCENTIVE PLAN)

         This Second Amendment to the Caremark Rx, Inc. 1994 Stock Incentive
Plan (formerly the Medpartners, Inc. 1994 Stock Incentive Plan) (the "Plan") to
be effective as of January 12, 2001.

                                   WITNESSETH:

         WHEREAS, Caremark Rx, Inc. (the "Company") currently sponsors and
maintains the Caremark Rx, Inc. 1994 Stock Incentive Plan (formerly the
Medpartners, Inc. 1994 Stock Incentive Plan) (the "Plan"); and

         WHEREAS, Section 14 of the Plan grants the Compensation Committee of
the Board the power at any time to amend the Plan, and the Compensation
Committee now wishes to amend the Plan to modify the vesting provisions for
options granted under the Plan on and after January 12, 2001;

         NOW, THEREFORE, the Plan is hereby amended as indicated below:

                                       1.

         Section 7(i) of the Plan is amended effective as of January 12, 2001,
to read as follows:

                  (i)      Vesting of Options. Except as set forth by the
         Committee in the applicable Stock Option Agreement, Options granted
         under the Plan shall vest and become exercisable as follows:

                           (i)      34% of the Options shall vest on the Date of
                  Grant;

                           (ii)     33% of the Options granted shall vest on
                  each of the first anniversary and second anniversary of the
                  Date of Grant; provided, however, that for Options granted
                  prior to January 12, 2001, if during the first year after the
                  Date of Grant, the stock price of the Common Stock closes at
                  or above $12.00 (or such other price as determined by the
                  Committee and set forth in the applicable Stock Option
                  Agreement) for any twenty (20) out of thirty (30) consecutive
                  trading days, the 33% of the Options due to vest on the first
                  anniversary of the Date of Grant shall vest immediately at the
                  end of such 20th day, and provided, however, that for Options
                  granted prior to January 12, 2001, if during the second year
                  after the Date of Grant, the stock price of the Common


                             Second Amendment to the
                   Caremark Rx, Inc. 1994 Stock Incentive Plan
                                     Page 1


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                  Stock closes at or above $18.00 (or such other price as
                  determined by the Committee and set forth in the applicable
                  Stock Option Agreement) for any twenty (20) out of thirty (30)
                  consecutive trading days, the 33% of the Options due to vest
                  on the second anniversary of the Date of Grant shall vest
                  immediately at the end of such 20th day.

                                       2.

         The name of the Plan is changed effective as of January 12, 2001 from
the Medpartners, Inc. 1994 Stock Incentive Plan to the Caremark Rx, Inc. 1994
Stock Incentive Plan. All references in any Company documents to the
Medpartners, Inc. 1994 Stock Incentive Plan shall, after January 12, 2001, be a
reference to the Caremark Rx, Inc. 1994 Stock Incentive Plan.

                                       3.

         All other provisions of the Plan not inconsistent herewith are hereby
confirmed and ratified.

                       Approved by the Board of Directors
                       by resolutions on January 12, 2001.



                             Second Amendment to the
                   Caremark Rx, Inc. 1994 Stock Incentive Plan
                                     Page 2