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                                                                   EXHIBIT 10.19


                                SECOND AMENDMENT
                                     TO THE
                   CAREMARK RX, INC. 1992 STOCK INCENTIVE PLAN
                        (FORMERLY THE AMENDED & RESTATED
                 MEDPARTNERS, INC. INCENTIVE COMPENSATION PLAN)

         This Second Amendment to the Caremark Rx, Inc. 1992 Stock Incentive
Plan (formerly the Amended & Restated Medpartners, Inc. Incentive Compensation
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. 1992 Stock Incentive Plan (formerly the Amended
& Restated Medpartners, Inc. Incentive Compensation Plan) (the "Plan"); and

         WHEREAS, Section 7.9 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;

         RESOLVED, the Plan is hereby amended as indicated below:

                                       1.

         Section 5.4 of the Plan is amended effective as of January 12, 2001, to
read as follows:

                  5.4      Vesting of Stock Options.

                  Except as provided by the Committee in the applicable Award
                  Agreement, Stock Options shall vest and become exercisable as
                  follows:

                           (a)      34% of the Stock Options granted shall vest
                  on the Stock Option grant date;

                           (b)      33% of the Stock Options granted shall vest
                  on each of the first anniversary and second anniversary of the
                  Stock Option grant date; provided, however, that for Stock
                  Options granted prior to January 12, 2001, if during the first
                  year after the Stock Option grant date, 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
                  Award Agreement) for any twenty (20) out of thirty (30)
                  consecutive trading days, the 33% of the Stock Options due to
                  vest on the first anniversary of the Stock Option



                             Second Amendment to the
                   Caremark Rx, Inc. 1992 Stock Incentive Plan
                                     Page 1

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                  grant date shall vest immediately at the end of such 20th day,
                  and provided, however, that for Stock Options granted prior to
                  January 12, 2001, if during the second year after the Stock
                  Option grant date, the stock price of the Common Stock closes
                  at or above $18.00 (or such other price as determined by the
                  Committee and set forth in the applicable Award Agreement) for
                  any twenty (20) out of thirty (30) consecutive trading days,
                  the 33% of the Stock Options due to vest on the second
                  anniversary of the Stock Option grant date 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 Amended & Restated Medpartners, Inc. Incentive Compensation Plan to the
Caremark Rx, Inc. 1992 Stock Incentive Plan. All references in any Company
documents to the Amended & Restated Medpartners, Inc. Incentive Compensation
Plan shall, after January 12, 2001, be a reference to the Caremark Rx, Inc. 1992
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. 1992 Stock Incentive Plan
                                     Page 2