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                                                                    EXHIBIT 10.5


                              AMENDED AND RESTATED

                                CAREMARK RX, INC.

                             1993 STOCK OPTION PLAN


                  1.       PURPOSE OF THE PLAN

                  The purposes of this Amended and Restated Caremark Rx, Inc.
("Caremark Rx" or the "Company") 1993 Stock Option Plan (the "Plan") are to:

                  1.1.     furnish incentives to individuals or entities chosen
to receive options because they are considered capable of responding by
improving operations and increasing profits;

                  1.2.     encourage selected employees to accept or continue
employment with the Company or its Affiliates; and

                  1.3.     increase the interest of selected employees,
officers, directors and consultants in the Company's welfare through their
participation in the growth in value of the common stock, $.001 par value, of
the Company ("Common Stock").

                  To accomplish the foregoing objectives, this Plan provides a
means whereby individuals and entities may receive options to purchase Common
Stock. Options granted under this Plan ("Options") will be either nonqualified
options ("NQOs") or incentive stock options ("ISOs").

                  2.       ELIGIBLE PERSONS

                  2.1.     General. Every person who at the date on which an
Option granted to such person becomes effective (the "Grant Date") is a
full-time employee, officer, director or consultant of the Company or of any
Affiliate or any individual or entity subject to an acquisition or management
agreement with the Company is eligible to receive Options under this Plan.

                  2.2.     Definition of Affiliate. The term "Affiliate," as
used in this Plan, means a "parent corporation" or "subsidiary corporation," as
defined in Section 424 of the Internal Revenue Code of 1986 (as amended, the
"Code"). The term "employee" shall have the meaning ascribed for purposes of
Section 3401(c) of the Code and the Treasury Regulations promulgated thereunder
and shall include an officer or a director who is also an employee.

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                  3.       STOCK SUBJECT TO THIS PLAN

                  The total number of shares of stock reserved for issuance upon
the exercise of Options is 1,555,000 shares of Common Stock, divided into
500,000 shares of Common Stock reserved for issuance upon the exercise of
options that may be granted in connection with the acquisition of the assets of
or management of physician practices (hereinafter referred to as "Acquisition
Options") and 1,055,000 shares of Common Stock reserved for issuance upon the
exercise of options granted to employees, officers, consultants and members of
the Board of Directors of the Company (hereinafter referred to as "Management
Options"). The shares covered by the portion of any grant that expires
unexercised under this Plan shall become available again for grants under this
Plan; provided, however, that no Management Options may be granted as
Acquisition Options and vice versa. The number of shares reserved for issuance
under this Plan is subject to adjustment in accordance with the provisions for
adjustment in this Plan.

                  4.       ADMINISTRATION

                  4.1.     General. This Plan shall be administered by the
Compensation Committee of the Board of Directors or by any other committee
appointed by the Board of Directors (the "Committee"), which Committee shall
consist solely of two or more Non-Employee Directors ("Non-Employee Directors")
as such are defined in Rule 16b-3 promulgated pursuant to the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), or any successor
provision. The Committee shall have the authority to select the persons to
receive Options under this Plan, to fix the number of shares that each optionee
may purchase, to set the terms and conditions of each Option, and to determine
all other matters relating to this Plan. Any act approved in writing by a
majority of the members of the Committee shall be a valid act of the Committee.
All questions of interpretation, construction, implementation and application of
this Plan and any Option Agreement awarded under it shall be determined by the
Committee. Such determinations shall be final and binding on all persons. No
member of the Board of Directors or the Committee shall be liable for any action
or determination made in good faith with respect to the Plan or any Option
granted under the Plan.

                  5.       GRANTING OF RIGHTS

                  5.1.     Ten Year Limitation on Grants of ISOs. No ISOs shall
be granted under this Plan after ten years from the date the Board of Directors
first adopts the Plan.

                  5.2.     Written Agreement; Effect. Each Option shall be
evidenced by a written agreement (the "Option Agreement"), in form satisfactory
to the Committee, executed by the Company and by the person to whom such Option
is granted. Each such Option Agreement shall incorporate by reference all of the
terms and conditions of the Plan as in effect at the time of its execution and
may contain such other terms and provisions not contrary to the Plan as shall be
approved and adopted by the Committee. The Option Agreement shall specify
whether each Option it evidences is a NQO or an ISO. Failure of the grantee to
execute an Option Agreement shall not void or invalidate


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the grant of an Option; the Option may not be exercised, however, until the
Option Agreement is executed.

                  5.3.     Annual $100,000 Limitation on ISOs. To the extent
required by Section 422(d) of the Code, the aggregate fair market value of
shares of the Common Stock with respect to which incentive stock options are
exercisable for the first time by any individual during any calendar year shall
not exceed $100,000. For this purpose, fair market value shall be the fair
market value of the shares covered by the ISOs when the ISOs were granted. If by
their terms, such ISOs taken together would first become exercisable at a faster
rate, this $100,000 limitation shall be applied by deferring the exercisability
of those ISOs or portions of ISOs which have the highest per share exercise
prices. The ISOs or portions of ISOs, the exercisability of which are so
deferred, shall become exercisable on the first day of the first subsequent
calendar year during which they may be exercised, as determined by applying
these same principles of this Section and all other provisions of this Section
and all other provisions of this Plan, including those relating to the
expiration and termination of ISOs.

                  5.4.     Advance Approvals. The Committee may approve the
grant of Options to persons who are expected to become employees, consultants or
members of the Board of Directors, of the Company, but are not employees,
consultants or members of the Board of Directors at the date of approval. In
such cases, the Option shall be deemed granted, without further approval, on the
date the grantee becomes an employee, and must satisfy all requirements of this
Plan for Options granted on that date.

                  6.       TERMS AND CONDITIONS OF OPTIONS

                  Each Option shall be designated as an ISO or a NQO and shall
be subject to the terms and conditions set forth in Section 6.1. NQOs shall also
be subject to the terms and conditions set forth in Section 6.2, but not those
set forth in Section 6.3. ISOs shall also be subject to the terms and conditions
set forth in Section 6.3, but not those set forth in Section 6.2.

                  6.1.     Terms and Conditions to Which All Options Are
Subject. All Options shall be subject to the following terms and conditions:

                  (a)      Changes in Capital Structure. Subject to Section
         6.1(b), if the stock of the Company is changed by reason of a stock
         split, reverse stock split, stock dividend, or recapitalization, or
         converted into or exchanged for other securities as a result of a
         merger, consolidation, or reorganization, appropriate adjustments shall
         be made in (1) the number and class of shares of stock subject to this
         Plan and each outstanding Option, and (2) the exercise price of each
         outstanding Option; provided, however, that the Company shall not be
         required to issue fractional shares as a result of any such adjustment.
         Each such adjustment shall be determined by the Committee in its sole
         discretion, which determination shall be final and binding on all
         persons.


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                  (b)      Corporate Transactions. New option rights may be
         substituted for Options granted, or the Company's obligations as to
         outstanding Options may be assumed, by an employer corporation other
         than the Company, or an Affiliate thereof, in connection with any
         merger, consolidation, acquisition, separation, reorganization,
         dissolution, liquidation, sale, or like occurrence in which the Company
         is involved and which the Committee determines, in its absolute
         discretion, would materially alter the structure. Substitution shall be
         done in such manner that the then outstanding Options which are ISOs
         will continue to be "incentive stock options" within the meaning of
         Section 422 of the Code to the full extent permitted thereby.
         Notwithstanding the foregoing or the provisions of Section 6.1(a), if
         such an event occurs and if such employer corporation, or an Affiliate
         thereof, does not substitute new option rights for, and substantially
         equivalent to, the outstanding Options granted hereunder, or assume the
         outstanding Options granted hereunder, or if there is no employer
         corporation, or if the Committee determines, in its sole discretion,
         that outstanding Options should not then continue to be outstanding,
         the Committee may upon ten days' prior written notice to optionees in
         its absolute discretion (1) shorten the period during which Options are
         exercisable (provided they remain exercisable, to the extent otherwise
         exercisable, for at least ten days after the date the notice is given),
         or (2) cancel Options upon payment to the optionee in cash, with
         respect to each Option to the extent then exercisable, of an amount
         which, in the absolute discretion of the Committee, is determined to be
         equivalent to any excess of the fair market value (at the effective
         time of the dissolution, liquidation, merger, consolidation,
         acquisition, separation, reorganization, sale or other event) of the
         consideration that the optionee would have received if the Option had
         been exercised before the effective time, over the exercise price of
         the Option; provided, however, if there is a successor corporation and
         replacement options are not granted by the successor corporation, all
         outstanding Options shall become exercisable prior to the consummation
         of the transaction such that the optionees shall have not less than ten
         days to exercise their Options and become stockholders of record
         entitled to receive the consideration paid to the other stockholders of
         the Company. If an optionee fails to exercise his Option within any
         exercise period described in this paragraph and the dissolution,
         liquidation, merger, consolidation, sale or other event is consummated,
         his Option shall no longer be exercisable. Any unexercised Option shall
         be canceled and terminated. Notwithstanding anything herein to the
         contrary, nothing shall extend an optionee's right to exercise an ISO
         after the expiration of ten years from the date it is granted. The
         actions described in this Section may be taken without regard to any
         resulting tax consequences to the optionee.

                  (c)      Option Grant Date. Each Option Agreement shall
         specify the date as of which it shall be effective, which date shall be
         the Grant Date (determined pursuant to Section 5.4 in the case of
         advance approvals).

                  (d)      Fair Market Value. Except as otherwise determined by
         the Committee, the "Fair Market Value" of a share of Common Stock as of
         any date shall be equal to the closing sale price of a share of Common
         Stock as reported on


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         The National Association of Securities Dealers' New York Stock Exchange
         Composite Reporting Tape (or if the Common Stock is not traded on The
         New York Stock Exchange, the closing sale price on the exchange on
         which it is traded or as reported by an applicable automated quotation
         system) (the "Composite Tape"), on the applicable date or, if no sales
         of Common Stock are reported on such date, the closing sale price of a
         share of Common Stock on the date the Common Stock was last reported on
         the Composite Tape (or such other exchange or automated quotation
         system, if applicable).

                  (e)      Transfer of Option Rights.

                           (1)      Incentive Stock Options. No ISO granted
                  under the Plan may be sold, transferred, pledged, assigned, or
                  otherwise alienated or hypothecated, other than by will or by
                  the laws of descent and distribution. Further, all ISOs
                  granted to an optionee under the Plan shall be exercisable
                  during his or her lifetime only by such optionee.

                           (2)      Nonqualified Stock Options. No NQO granted
                  under the 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 Plan, the Options or the
                  registration with the Securities and Exchange Commission of
                  the Common Stock to be issued upon exercise of the Options,
                  the Committee may, in its discretion, authorize all or a
                  portion of NQOs granted to an optionee to be on terms which
                  permit transfer by such optionee to (i) the spouse, children
                  or grandchildren of the optionee ("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
                  (x) there may be no consideration for any such transfer, (y)
                  the Option Agreement pursuant to which such NQOs are granted
                  must be approved by the Committee, and must expressly provide
                  for transferability in a manner consistent with this Section,
                  and (z) subsequent transfers of transferred NQOs shall be
                  prohibited except those by will or the laws of descent and
                  distribution. Following transfer, any such NQOs shall continue
                  to be subject to the same terms and conditions as were
                  applicable immediately prior to transfer, provided that for
                  purposes of this Plan, the term "optionee" shall be deemed to
                  refer to the transferee. The events of termination of
                  employment shall continue to be applied with respect to the
                  original optionee, following which the NQOs shall be
                  exercisable by the transferee only to the extent, and for the
                  periods specified in Section 6.1(g). Notwithstanding the
                  foregoing, should the Committee provide that NQOs 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 NQO. In the event of a transfer, as set
                  forth above, the original optionee is and will remain subject
                  to and


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                  responsible for any applicable withholding taxes upon the
                  exercise of such NQOs.

                  (f)      Payment. No shares of Common Stock shall be issued on
         the exercise of an Option unless paid for in full at the time of
         exercise. Payment shall be made in cash, which may be paid by check or
         other instrument acceptable to the Company. In addition, subject to
         compliance with applicable laws and regulations and such conditions as
         the Committee may impose, the Committee may elect to accept payment in
         shares of Common Stock of the Company which are already owned by the
         optionee, valued at the Fair Market Value thereof on the date of
         exercise. The Committee may also allow an optionee to exercise an
         option by use of proceeds to be received from the sale of Common Stock
         issuable pursuant to the Option being exercised.

                  (g)      Termination. Except as otherwise provided in an
         Option Agreement or as provided in paragraphs (h) and (i) below, each
         Option to the extent it has not been previously exercised, shall
         terminate upon the earliest to occur of: (a) the expiration of the term
         of the Option set forth in the Option Agreement; (b) immediately upon
         the date the optionee ceases to be an employee, officer, consultant or
         member of the Board of Directors or otherwise affiliated with the
         Company (a "Termination") on account of cause; (c) the expiration of 90
         days following the date of a Termination of the optionee for any reason
         other than cause, death or permanent disability or (d) the expiration
         of 12 months following a Termination of the optionee on account of
         death or permanent disability. A leave of absence duly authorized by
         the Company shall not be deemed a Termination or a break in continuous
         employment, service or affiliation with the Company.

                  (h)      Except as otherwise provided in an Option Agreement,
         any Option granted after September 21, 1998 (a "Secondary Option"), to
         the extent it has not been previously exercised, shall terminate upon
         the earliest to occur of: (a) the expiration of the Secondary Option
         period set forth in the Option Agreement; (b) the expiration of 12
         months following the optionee's death or permanent disability; (c)
         immediately upon Termination for Cause (as defined below); or (d) the
         expiration of 90 days following the optionee's Termination for any
         reason other than Cause (as defined below), Change in Control (as
         defined in Section 7 heretofore), death or permanent disability.

                           For purposes of the preceding sentence only, Cause
         means the Company or an Affiliate having cause to terminate an
         optionee's status as an employee, officer, consultant or director or
         other affiliation with the Company under any existing employment
         agreement between the optionee and the Company or an Affiliate or, in
         the absence of such an employment agreement, upon (i) the determination
         by the Committee that the optionee has ceased to perform his duties to
         the Company or an Affiliate (other than as a result of his incapacity
         due to physical or mental illness or injury), which failure amounts to
         an intentional and extended neglect of his duties to such party, (ii)
         the Committee's


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         determination that the optionee has engaged or is about to engage in
         conduct materially injurious to the Company or an Affiliate, or (iii)
         the optionee having been convicted of a felony.

                  (i)      Notwithstanding the foregoing, any Secondary Option,
         to the extent it has not been previously exercised prior to a Change in
         Control (as defined in Article 7 heretofore) shall remain exercisable
         for its full original term upon and following such Change in Control.

                  (j)      Other Provisions. Each Option Agreement may contain
         such other terms, provisions, and conditions not inconsistent with this
         Plan, including rights of repurchase, as may be determined by the
         Committee, and each ISO granted under this Plan shall include such
         provisions and conditions as are necessary to qualify such option as an
         "incentive stock option" within the meaning of Section 422 of the Code.

                  (k)      Withholding and Employment Taxes. At the time of
         exercise of an Option, the optionee shall remit to the Company in cash
         all applicable federal and state withholding and employment taxes. If
         and to the extent authorized and approved by the Committee in its sole
         discretion, an optionee may elect, by means of a form of election to be
         prescribed by the Committee, to have shares which are acquired upon
         exercise of an Option withheld by the Company or tender other shares of
         Common Stock or other securities of the Company owned by the optionee
         to the Company at the time the amount of such taxes is determined in
         order to pay the amount of such tax obligations, subject to the
         following limitations:

                           (1)      such election shall be irrevocable; and

                           (2)      such election shall be subject to the
                  disapproval of the Committee at any time.

                  Any Common Stock or other securities so withheld or tendered
will be valued by the Company as of the date they are withheld or tendered.
Unless the Committee otherwise determines, the optionee shall pay to the Company
in cash, promptly when the amount of such obligations become determinable, all
applicable federal and state withholding taxes resulting from the lapse of
restrictions imposed on exercise of an Option, from a transfer or other
disposition of shares acquired upon exercise of an Option or otherwise related
to the Option or the shares acquired upon exercise of the Option.

                  6.2.     Terms and Conditions to Which Only NQOs Are Subject.
Options granted under this Plan which are designated as NQOs shall be subject to
the following terms and conditions:

                  (a)      Option Term. Unless a different expiration date is
         specified by the Committee at the Grant Date in the Option Agreement,
         each NQO shall expire ten years from its Grant Date.


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                  6.3.     Terms and Conditions to Which Only ISOs Are Subject.
Options granted under this Plan which are designated as ISOs shall be subject to
the following terms and conditions:

                  (a)      Exercise Price. The exercise price of an ISO shall be
         determined in accordance with the applicable provisions of the Code and
         shall in no event be less than the fair market value of the stock
         covered by the ISO at the Grant Date; provided, however, that the
         exercise price of an ISO granted to any person who owns, directly or
         indirectly (or is treated as owning by reason of attribution rules,
         currently set forth in Section 424 of the Code), stock of the Company
         constituting more than 10% of the total combined voting power of all
         classes of outstanding stock of the Company or of any Affiliate of the
         Company, shall in no event be less than 110% of such fair market value.

                  (b)      Option Term. Unless an earlier expiration date is
         specified by the Committee at the Grant Date in the Option Agreement,
         each ISO shall expire ten years from its Grant Date; except that an ISO
         granted to any person who owns, directly or indirectly (or is treated
         as owning by reason of applicable attribution rules currently set forth
         in Section 424 of the Code) stock of the Company constituting more than
         10% of the total combined voting power of the Company's outstanding
         stock, or the stock of any Affiliate of the Company, shall expire five
         years from its Grant Date.

                  (c)      Disqualifying Dispositions. If stock acquired by
         exercise of an ISO is disposed of within two years from the Grant Date
         or within one year after the transfer of the stock to the optionee, the
         holder of the stock immediately prior to the disposition shall promptly
         notify the Company in writing of the date and terms of the disposition
         and shall provide such other information regarding the disposition as
         the Company may reasonably require. Such holder shall pay to the
         Company any withholding and employment taxes which the Company in its
         sole discretion deems applicable. The Company may instruct its stock
         transfer agent by appropriate means, including placement of legends on
         stock certificates, not to transfer stock acquired by exercise of an
         ISO unless it has been advised by the Company that the requirements of
         this Section have been satisfied.

                  6.4.     Vesting of Options. Except as set forth by the
Committee in the applicable Option Agreement, Options shall vest and become
exercisable as follows:

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

                  (b)      33% of the Options granted shall vest on each of the
         first anniversary and second anniversary of the Grant Date; provided,
         however, that if during the first year after the Grant Date, the stock
         price of the Common Stock closes at or above $12.00 (or such other
         price determined by the Committee and set forth in the applicable
         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 Grant Date shall vest immediately at the end of such
         20th day,


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         and provided, however, that if during the second year after the Grant
         Date, the stock price of the Common Stock closes at or above $18.00 (or
         such other price determined by the Committee and set forth in the
         applicable 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 Grant Date shall vest immediately at the end
         of such 20th day.

                  7.       CHANGE IN CONTROL

                  (a)      Treatment of Outstanding Options. Unless otherwise
         specifically prohibited under applicable laws, or by the rules and
         regulations of any governing governmental agencies or national
         securities exchanges, upon the occurrence of a Change in Control, any
         and all Secondary Options granted hereunder shall become immediately
         exercisable.

                  (b)      Termination, Modification or Amendment of Change in
         Control Provisions. Notwithstanding any other provision of this Plan or
         any Option Agreement provision, the provisions of this Article 7 may
         not be terminated, amended, or modified on or after the date of a
         Change in Control to affect adversely any Option theretofore granted
         under the Plan without the prior written consent of the optionee with
         respect to said optionee's outstanding Options.

                  (c)      Definition of Change in Control. A Change in Control
         of the Company shall be deemed to have occurred as of the first day
         that any one or more of the following conditions shall have been
         satisfied:

                           (1)      The acquisition by any Person of Beneficial
                  Ownership of 20% or more of either (i) the then outstanding
                  shares of Common Stock of the Company, or (ii) the combined
                  voting power of the outstanding voting securities of the
                  Company entitled to vote generally in the selection of
                  Directors; provided, however, that for purposes of this
                  subsection, the following transactions shall not constitute a
                  Change of Control: (A) any acquisition directly from the
                  Company through a public offering of shares of Common Stock of
                  the Company, (B) any acquisition by the Company, (C) any
                  acquisition by any employee benefit plan (or related trust)
                  sponsored or maintained by the Company or any corporation
                  controlled by the Company, or (D) any acquisition by any
                  corporation pursuant to a transaction which complies with
                  clauses (i), (ii) and (iii) of subsection (3) below;

                           (2)      The cessation, for any reason, of the
                  individuals who constitute the Company's Board of Directors as
                  of the date hereof ("Incumbent Board") to constitute at least
                  a majority of the Company's Board of Directors; provided,
                  however, that any individual becoming a Director following the
                  date hereof whose election, or nomination for election by the
                  Company's stockholders, was approved by a vote of at least a
                  majority of the Directors then comprising the Incumbent Board
                  shall be


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                  considered as though such individual was a member of the
                  Incumbent Board, but excluding, for this purpose, any such
                  individual whose initial assumption of office occurs because
                  of an actual or threatened election contest with respect to
                  the election or removal of Directors or other actual or
                  threatened solicitation of proxies or consents by or on behalf
                  of a Person other than the Company's Board of Directors;

                           (3)      The consummation of a reorganization, merger
                  or consolidation or sale or other disposition of all or
                  substantially all of the assets of the Company ("Business
                  Combination") unless, following such Business Combination, (i)
                  all or substantially all of the individuals and entities who
                  were the Beneficial Owners, respectively, of the outstanding
                  shares of Common Stock of the Company and the outstanding
                  voting securities of the Company immediately before such
                  Business Combination beneficially own, directly or indirectly,
                  more than 50% of, respectively, the then outstanding shares of
                  Common Stock and the combined voting power of the then
                  outstanding voting securities entitled to vote generally in
                  the election of Directors, as the case may be, of the Company
                  resulting from such Business Combination (including, without
                  limitation, a corporation which as a result of such
                  transaction owns the Company or all or substantially all of
                  the Company's assets either directly or through one or more
                  subsidiaries) in substantially the same proportions as their
                  ownership immediately before such Business Combination of the
                  outstanding shares of Common Stock and the outstanding voting
                  securities of the Company, as the case may be; (ii) no party
                  (excluding any corporation resulting from such Business
                  Combination or any employee benefit plan (or related trust) of
                  the Company or such corporation resulting from such Business
                  Combination) beneficially owns, directly or indirectly, 20% or
                  more of, respectively, the then outstanding shares of common
                  stock of the corporation resulting from such Business
                  Combination or the combined voting power of the then
                  outstanding voting securities of such corporation except to
                  the extent that such ownership existed before the Business
                  Combination; and (iii) at least a majority of the members of
                  the board of directors of the corporation resulting from such
                  Business Combination were members of the Company's Board of
                  Directors at the time of the execution of the initial
                  agreement, or of the action of the Company's Board of
                  Directors, providing for such Business Combination; or

                           (4)      The approval by the stockholders of the
                  Company of a complete liquidation or dissolution of the
                  Company.

                           (5)      Any other condition or event (i) that the
                  Committee determines to be a "Change in Control" within the
                  meaning of this Article 7 and (ii) that is set forth as a
                  supplement to this Article 7 in the Option Agreement.


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                  The term "Beneficial Owner" or "Beneficial Ownership", as used
in this Article 7, has the meaning ascribed to such term in Rule 13d-3 of the
General Rules and Regulations under the Exchange Act. The term "Person", as used
in this Article 7, shall have the meaning ascribed to such term in Section
3(a)(9) of the Exchange Act and used in Sections 13(d) and 14(d) thereof,
including a "group" as defined in Section 13(d) thereof.

                  8.       SALE OF BUSINESS UNIT OF COMPANY

                  The Committee, in connection with the sale of any subsidiary,
Affiliate, division or other business unit of the Company, may within the
Committee's sole and absolute discretion cause any or all Options granted
hereunder to optionees whose Options or rights under Options will be adversely
affected by such transaction (a) to become immediately exercisable, or (b) to
remain exercisable after such transaction for such period as the Committee deems
appropriate under the circumstances, or both (a) and (b). The provision of this
Article 8 and the actions of the Committee taken pursuant to this Article 8
shall be effective upon action of the Committee alone without amendment to any
option agreement or the consent of any optionee.

                  9.       MANNER OF EXERCISE

                  An optionee wishing to exercise an Option shall give proper
notification to the Company at its principal executive office, to the attention
of the Corporate Secretary, accompanied by a notice of exercise in form and
substance satisfactory to the Company, by payment of the exercise price for such
shares in a form and manner as the Committee may from time to time approve and
by such other documents as the Committee may request. The date the Company
receives proper notification of an exercise hereunder accompanied by payment of
the exercise price and all such other documents will be considered the date the
Option was exercised. Promptly after receipt of proper notification of exercise
of an Option, the Company shall, without stock issue or transfer taxes to the
optionee or any other person entitled to exercise the Option, deliver to the
optionee or such other person a certificate or certificates for the requisite
number of shares of stock. An optionee or transferee of an Option shall not have
any privileges as stockholder with respect to any stock covered by the Option
until the date of issuance of a stock certificate.

                  10.      RELATIONSHIP WITH THE COMPANY

                  Nothing in this Plan or any Option granted hereunder shall
interfere with or limit in any way the right of the Company to terminate any
optionee's employment, affiliation or other relationship with the Company at any
time, nor confer upon any optionee any right to continue in the employ of, as a
consultant to, as a director of, or otherwise affiliated in any way with, the
Company.


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                  11.      AMENDMENT, SUSPENSION OR TERMINATION OF THIS PLAN

                  The Committee may, at any time and in any manner, amend,
suspend, or termination this Plan or any award outstanding under this Plan;
provided, however, that no such amendment or discontinuance shall:

                  (a)      be made without stockholder approval: (1) to the
         extent such approval is required by law, agreement or the rules of any
         exchange or automated quotation system upon which the Common Stock is
         listed or quoted or (2) to the extent that any outstanding Option is
         canceled and regranted or repriced;

                  (b)      adversely alter or impair the rights of optionees
         with respect to awards previously made under this Plan without the
         consent of the holder thereof; or

                  (c)      make any change that would disqualify any provision
         of this Plan intended to be so qualified, from the exemption provided
         by Rule 16b-3.

                  12.      LIABILITY AND INDEMNIFICATION OF COMMITTEE

                  No member of the Committee shall be liable for any act or
omission on such member's own part, including, but not limited to, the exercise
of any power or discretion given to such member under this Plan, except for
those acts or omissions resulting from such member's own gross negligence or
willful misconduct. The Company shall indemnify each present and future member
of the Committee against, and each member of the Committee shall be entitled
without further act on his or her part to indemnity from the Company for, all
expenses (including attorneys' fees and the amount of judgments and the amount
of approved settlements made with a view to the curtailment of costs of
litigation, other than amounts paid to the Company itself) reasonably incurred
by such person in connection with or arising out of any action, suit, or
proceeding to which the Committee or any member of the Committee may be a party
by reason of any action taken or failure to act under or in connection with the
Plan or any option granted or not granted under the Plan to the full extent
permitted by law and by the Certificate of Incorporation and Bylaws of the
Company, as amended. The right of indemnity described in this Article 12 shall
be in addition to such other rights of indemnification as the members of the
Committee shall otherwise be entitled because of their serving on the Board of
Directors of the Company or as an employee of the Company.

                  13.      EFFECTIVE DATE OF THIS PLAN

                  This Plan first became effective upon adoption by the Board of
Directors on December 16, 1993 and was amended and restated on May 12, 1997.
This Amended and Restated Caremark Rx, Inc. 1993 Stock Option Plan is an
amendment and restatement of that Plan and was adopted by the Committee on
January __, 1999.


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