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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                  FORM 10-Q/A

                                AMENDMENT NO. 1
(MARK ONE)

<TABLE>
<C>        <S>
   [X]     QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
           SECURITIES EXCHANGE ACT OF 1934
           FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 1999
                                  OR

   [  ]    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
           SECURITIES EXCHANGE ACT OF 1934
           FOR THE TRANSITION PERIOD FROM --------------- TO
           ---------------
</TABLE>

                        COMMISSION FILE NUMBER: 0-27276

                               CAREMARK RX, INC.
             (Exact Name of Registrant as Specified in its Charter)

<TABLE>
<S>                                                 <C>
                     DELAWARE                                           63-1151076
          (State or other jurisdiction of                            (I.R.S. Employer
          incorporation or organization)                            Identification No.)
</TABLE>

                        3000 GALLERIA TOWER, SUITE 1000
                           BIRMINGHAM, ALABAMA 35244
                    (Address of principal executive offices)

                                 (205)733-8996
              (Registrant's telephone number, including area code)
                          (Formerly MedPartners, Inc.)

     Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ].

     Indicate the number of shares outstanding of each of the issuer's classes
of common stock, as of the latest practicable date.

<TABLE>
<CAPTION>
                    CLASS                             OUTSTANDING AT NOVEMBER 1, 1999
                    -----                             -------------------------------
<S>                                            <C>
   Common Stock, Par Value $.001 Per Share                      199,566,476
</TABLE>

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

* Includes 8,419,952 shares held in trust to be utilized in employee benefit
plans.

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EXPLANATORY NOTE

     The purpose of this amendment is solely for the addition of the following
documents, utilized in connection with the offering in September 1999, of 7%
Shared Preference Redeemable Securities ("SPuRS") of Caremark Rx Capital Trust
I, to the Company's Form 10-Q filed for the period ending September 30, 1999.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

     (a) Exhibits

     The exhibits required by Regulation S-K are set forth in the following
list:

<TABLE>
<CAPTION>
EXHIBIT NO.                               DESCRIPTION
-----------                               -----------
<S>          <C>  <C>
    4.1       --  Certificate of Trust of Caremark Rx Capital Trust I
    4.2       --  Trust Agreement of Caremark Rx Capital Trust I dated as of
                  September 10, 1999, between Caremark Rx, Inc., the
                  Wilmington Trust Company and the Administrative Trustees
                  named therein
    4.3       --  Amended and Restated Trust Agreement dated as of September
                  29, 1999 between Caremark Rx, Inc., the Wilmington Trust
                  Company, and the Holders named therein.
    4.4       --  Indenture for the Convertible Subordinated Debentures due
                  2029 dated as of September 29, 1999 between Caremark Rx,
                  Inc. and the Wilmington Trust Company
    4.5       --  Form of Common Securities
    4.6       --  Form of SPuRS
    4.7       --  Form of Convertible Subordinated Debentures due 2029
    4.8       --  Guarantee Agreement dated as of September 29, 1999 between
                  Caremark Rx, Inc. and the Wilmington Trust Company.
   10.6       --  Registration Rights Agreement dated September 29, 1999 by
                  and among Caremark Rx Capital Trust I, Caremark Rx, Inc. and
                  Warburg Dillon Read LLC.
</TABLE>

                                          Caremark Rx, Inc.

                                          By:  /s/ JAMES H. DICKERSON, JR.
                                            ------------------------------------
                                                  James H. Dickerson, Jr.
                                                Executive Vice President and
                                                  Chief Financial Officer

                                          By:      /s/ HOWARD A. MCLURE
                                            ------------------------------------
                                                      Howard A. McLure
                                                 Senior Vice President and
                                                  Chief Accounting Officer

Date: December 3, 1999