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________________________________________________________________________________

                                                                    Exhibit 10.3

                                MERCK & CO., INC.

                          PLAN FOR DEFERRED PAYMENT OF

                             DIRECTORS' COMPENSATION

                      (Amended and Restated July 24, 2003)




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                                TABLE OF CONTENTS

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                                                                            Page
                                                                            ----
<S>                                                                         <C>
Article I   Purpose ......................................................     1

Article II  Election of Deferral, Measurement Methods and
              Distribution Schedule ......................................     1

Article III Valuation of Deferred Amounts ................................     2

Article IV  Redesignation Within a Deferral Account ......................     3

Article V   Payment of Deferred Amounts ..................................     4

Article VI  Designation of Beneficiary ...................................     5

Article VII Plan Amendment or Termination ................................     5

Schedule A  Measurement Methods ..........................................     6
</TABLE>


                                       (i)
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                                MERCK & CO., INC.
                          PLAN FOR DEFERRED PAYMENT OF
                             DIRECTORS' COMPENSATION

I.    PURPOSE

      To provide an arrangement under which directors of Merck & Co., Inc. other
      than current employees may (i) elect to voluntarily defer payment of the
      annual retainer and meeting and committee fees until after termination of
      their service as a director, and (ii) value compensation mandatorily
      deferred on their behalf.

II.   ELECTION OF DEFERRAL, MEASUREMENT METHODS AND
      DISTRIBUTION SCHEDULE

      A.    Election of Voluntary Deferral Amount

      1.    Prior to December 28 of each year, each director is entitled to make
            an irrevocable election to defer until termination of service as a
            director receipt of payment of (a) 50% or 100% of the retainer for
            the 12 months beginning April 1 of the next calendar year, (b) 50%
            or 100% of the Committee Chairperson retainer beginning April 1 of
            the next calendar year, and (c) 50% or 100% of the meeting and
            committee fees for the 12 months beginning April 1 of the next
            calendar year.

      2.    Prior to commencement of duties as a director, a director newly
            elected or appointed to the Board during a calendar year must make
            the election under this paragraph for the portion of the Voluntary
            Deferral Amount applicable to such director's first year of service
            (or part thereof).

      3.    The Voluntary Deferral Amount shall be credited as follows: (1)
            Meeting and committee fees that are deferred are credited as of the
            day the director's services are rendered; (2) if the Board retainer
            and/or Committee Chairperson retainer is deferred, a pro-rata share
            of the deferred retainer is credited on the last business day of
            each calendar quarter. The dates the Voluntary Deferral Amount, or
            parts thereof, are credited to the director's deferred account are
            hereinafter referred to as the Voluntary Deferral Dates.

      B.    Mandatory Deferral Amount

      1.    On the Friday following the Company's Annual Meeting of Stockholders
            (such Friday hereinafter referred to as the "Mandatory Deferral
            Date"), each director will be credited with an amount equivalent to
            one-third of the annual cash retainer for the 12 month period
            beginning on the April 1 preceding the Annual Meeting (the
            "Mandatory Deferral Amount"). The Mandatory Deferral Amount will be
            measured by the Merck Common Stock account.

      2.    A director newly elected or appointed to the Board after the
            Mandatory Deferral Date will be credited with a pro rata portion of
            the Mandatory Deferral Amount applicable to such director's first
            year of service (or part thereof). Such pro rata portion shall be
            credited to the director's account on the first day of such
            director's service.


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      C.    Election of Measurement Method

            Each such annual election referred to in Section A shall include an
            election as to the measurement method or methods by which the value
            of amounts deferred will be measured in accordance with Article III,
            below. The available measurement methods are set forth on Schedule A
            hereto.

      D.    Election of Distribution Schedule

            Each annual election referred to in Section A above shall also
            include an election to receive payment following termination of
            service as a director of all Voluntary Deferral Amounts and
            Mandatory Deferral Amounts in a lump sum either immediately or one
            year after such termination, or in quarterly or annual installments
            over five, ten or fifteen years.

III.  VALUATION OF DEFERRED AMOUNTS

      A.    Common Stock

      1.    Initial Crediting. The annual Mandatory Deferral Amount shall be
            used to determine the number of full and partial shares of Merck
            Common Stock which such amount would purchase at the closing price
            of the Common Stock on the New York Stock Exchange on the Mandatory
            Deferral Date.

            That portion of the Voluntary Deferral Amount allocated to Merck
            Common Stock shall be used to determine the number of full and
            partial shares of Merck Common Stock which such amount would
            purchase at the closing price of the Common Stock on the New York
            Stock Exchange on the applicable Voluntary Deferral Date.

            However, should it be determined by the Committee on Corporate
            Governance of the Board of Directors that a measurement of Merck
            Common Stock on any Mandatory or Voluntary Deferral Date would not
            constitute fair market value, then the Committee shall decide on
            which date fair market value shall be determined using the valuation
            method set forth in this Article III, Section A.1.

            At no time during the deferral period will any shares of Merck
            Common Stock be purchased or earmarked for such deferred amounts nor
            will any rights of a shareholder exist with respect to such amounts.

      2.    Dividends. Each director's account will be credited with the
            additional number of full and partial shares of Merck Common Stock
            which would have been purchasable with the dividends on shares
            previously credited to the account at the closing price of the
            Common Stock on the New York Stock Exchange on the date each
            dividend was paid.

      3.    Distributions. Distribution from the Merck Common Stock account will
            be valued at the closing price of Merck Common Stock on the New York
            Stock Exchange on the distribution date.


                                       2
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      B.    Mutual Funds

      1.    Initial Crediting. The amount allocated to each Mutual Fund shall be
            used to determine the full and partial Mutual Fund shares which such
            amount would purchase at the closing net asset value of the Mutual
            Fund shares on the Mandatory or Voluntary Deferral Date, whichever
            is applicable. The director's account will be credited with the
            number of full and partial Mutual Fund shares so determined.

            At no time during the deferral period will any Mutual Fund shares be
            purchased or earmarked for such deferred amounts nor will any rights
            of a shareholder exist with respect to such amounts.

      2.    Dividends. Each director's account will be credited with the
            additional number of full and partial Mutual Fund shares which would
            have been purchasable, at the closing net asset value of the Mutual
            Fund shares as of the date each dividend is paid on the Mutual Fund
            shares, with the dividends which would have been paid on the number
            of shares previously credited to such account (including pro rata
            dividends on any partial shares).

      3.    Distributions. Mutual Fund distributions will be valued based on the
            closing net asset value of the Mutual Fund shares on the
            distribution date.

      C.    Adjustments

            In the event of a reorganization, recapitalization, stock split,
            stock dividend, combination of shares, merger, consolidation, rights
            offering or any other change in the corporate structure or shares of
            the Company or a Mutual Fund, the number and kind of shares or units
            of such investment measurement method available under this Plan and
            credited to each director's account shall be adjusted accordingly.

IV.   REDESIGNATION WITHIN A DEFERRAL ACCOUNT

      A.    General

            A director may request a change in the measurement methods used to
            value all or a portion of his/her account other than Merck Common
            Stock. AMOUNTS DEFERRED USING THE MERCK COMMON STOCK METHOD AND ANY
            EARNINGS ATTRIBUTABLE TO SUCH DEFERRALS MAY NOT BE REDESIGNATED. The
            change will be effective on (i) the day when the redesignation
            request is received pursuant to administrative guidelines
            established by the Human Resources Financial Services area of the
            Treasury department, provided the request is received prior to the
            close of the New York Stock Exchange on such day or (ii) the next
            following business day if the request is received when the New York
            Stock Exchange is closed.

      B.    When Redesignation May Occur

      1.    During Active Service. There is no limit on the number of times a
            director may redesignate the portion of his/her deferred account
            permitted to be redesignated. Each such request shall be irrevocable
            and can be designated in whole percentages or as a dollar amount.


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      2.    After Death. Following the death of a director, the legal
            representative or beneficiary of such director may redesignate
            subject to the same rules as for active directors set forth in
            Article IV, Section B.1.

      C.    Valuation of Amounts to be Redesignated

            The portion of the director's account to be redesignated will be
            valued at its cash equivalent and such cash equivalent will be
            converted into shares or units of the other measurement method(s).
            For purposes of such redesignations, the cash equivalent of the
            value of the Mutual Fund shares shall be the closing net asset value
            of such Mutual Fund on (i) the day when the redesignation request is
            received pursuant to administrative guidelines established by the
            Human Resources Financial Services area of the Treasury department,
            provided the request is received prior to the close of the New York
            Stock Exchange on such day or (ii) the next following business day
            if the request is received when the New York Stock Exchange is
            closed.

V.    PAYMENT OF DEFERRED AMOUNTS

      A.    Payment

            All payments to directors of amounts deferred will be in cash in
            accordance with the distribution schedule elected by the director
            pursuant to Article II, Section D. Distributions shall be pro rata
            by measurement method. Distributions shall be valued on the
            fifteenth day of the distribution month (or, if such day is not a
            business day, the next business day) and paid as soon thereafter as
            possible.

      B.    Changes to Distribution Schedule Prior to Termination

            Upon the request of a director made at any time during the calendar
            year immediately preceding the calendar year in which service as a
            director is expected to terminate, the Committee on Corporate
            Governance of the Board of Directors, in its sole discretion, may
            authorize: (a) an extension of a payment period beyond that
            originally elected by the director not to exceed that otherwise
            allowable under Article II, Section D, and/or (b) a payment
            frequency different from that originally elected by the director.
            Such request may not be made with regard to amounts deferred after
            December 31, 1990 using the Merck Common Stock method and to any
            earnings attributable to such deferrals. Deferrals into Merck Common
            Stock made after December 31, 1990 and any earnings thereon may only
            be distributed in accordance with the schedule elected by the
            director under Article II, Section D or determined by the Committee
            on Corporate Governance under Article VI.

      C.    Post-Termination Changes to Distribution Schedule

            Following termination of service as a director, each director may
            make one request for a further extension of the period for
            distribution of his/her deferred compensation. Such request must be
            received by the Committee on Corporate Governance prior to the first
            distribution to the participant under his/her previously elected
            distribution schedule. Any revised distribution schedule may not
            exceed the deferral period otherwise allowable under Article II,
            Section C. This request may be granted and a new payment schedule
            determined in the sole discretion of the Committee on Corporate
            Governance.


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            Such request may not be made with regard to amounts deferred after
            December 31, 1990 using the Merck Common Stock Method and to any
            earnings attributable to such deferrals. Any retired director who is
            not subject to U.S. income tax may petition the Committee on
            Corporate Governance to change payment frequency, including a lump
            sum distribution, and the Committee on Corporate Governance may
            grant such petition if, in its discretion, it considers there to be
            reasonable justification therefor. Deferrals into Merck Common Stock
            made after December 30, 1990 and any earnings thereon may only be
            distributed in accordance with the schedule elected by the director
            under Article II, Section D or determined by the Committee on
            Corporate Governance under Article VI.

      D.    Forfeitures

            A director's deferred amount attributable to the Mandatory Deferral
            Amount and earnings thereon shall be forfeited upon his or her
            removal as a director or upon a determination by the Committee on
            Corporate Governance in its sole discretion, that a director has:

            (i)   joined the Board of, managed, operated, participated in a
                  material way in, entered employment with, performed consulting
                  (or any other) services for, or otherwise been connected in
                  any material manner with a company, corporation, enterprise,
                  firm, limited partnership, partnership, person, sole
                  proprietorship or any other business entity determined by the
                  Committee on Corporate Governance in its sole discretion to be
                  competitive with the business of the Company, its subsidiaries
                  or its affiliates (a "Competitor");

            (ii)  directly or indirectly acquired an equity interest of five (5)
                  percent or greater in a Competitor; or

            (iii) disclosed any material trade secrets or other material
                  confidential information, including customer lists, relating
                  to the Company or to the business of the Company to others,
                  including a Competitor.

VI.   DESIGNATION OF BENEFICIARY

      In the event of the death of a director, the deferred amount at the date
      of death shall be paid to the last named beneficiary or beneficiaries
      designated by the director, or, if no beneficiary has been designated, to
      the director's legal representative, in one or more installments as the
      Committee on Corporate Governance in its sole discretion may determine.

VII.  PLAN AMENDMENT OR TERMINATION

      The Committee on Corporate Governance shall have the right to amend or
      terminate this Plan at any time for any reason.


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                                   SCHEDULE A

                               MEASUREMENT METHODS
                      (JANUARY 1, 2002 - JANUARY 10, 2003)


      MERCK COMMON STOCK

      MUTUAL FUNDS

            American Century Emerging Markets Fund
            American Century Europacific Growth Fund
            Fidelity Destiny I
            Fidelity Dividend Growth
            Fidelity Equity Income Fund
            Fidelity Low-Priced Stock Fund
            Fidelity Retirement Money Market
            Fidelity Spartan Government Income
            Fidelity Spartan U.S. Equity Index
            Franklin Small-Mid Cap Growth A
            Janus Enterprise
            Janus Growth & Income
            Liberty Acorn Z
            PIMCO Foreign Bond Institutional
            PIMCO Long Term US Government Institutional
            PIMCO Total Return Institutional
            Putnam Global Equity Fund A*
            Putnam International Voyager A
            Putnam Vista A
            T. Rowe Price Blue Chip Growth Fund
            Vanguard Asset Allocation

            *From September 20, 2002 -- September 30, 2002, this investment was
      briefly named the Putnam Global Growth Fund A as a result of the merger,
      in September 2002, of Putnam Global Equity Fund A with Putnam Global
      Growth Fund A. The merged fund briefly retained the name "Putnam Global
      Growth Fund A." Effective October 1, 2002, the merged fund changed its
      name to "Putnam Global Equity Fund A."


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                                   SCHEDULE A

                               MEASUREMENT METHODS
                  (EFFECTIVE JANUARY 11, 2003 TO JULY 31, 2003)

      MERCK COMMON STOCK

      MUTUAL FUNDS

            American Century Emerging Markets Institutional
            American Funds EuroPacific Growth Fund
            Fidelity Destiny I
            Fidelity Dividend Growth
            Fidelity Equity-Income
            Fidelity Low-Priced Stock
            Fidelity Retirement Money Market
            Fidelity Spartan Government Income
            Fidelity Spartan U.S. Equity Index
            Franklin Small-Mid Cap Growth A
            Janus Enterprise
            Janus Growth & Income
            Liberty Acorn Class Z
            PIMCO Foreign Bond Institutional
            PIMCO Long Term US Government Institutional
            PIMCO Total Return Institutional
            Putnam Global Equity A
            Putnam International Capital Opportunities Fund A*
            Putnam Vista A
            T. Rowe Price Blue Chip Growth
            Vanguard Asset Allocation

* Prior to April 30, 2003, known as Putnam International Voyager Fund A.

REDESIGNATION OF DEFERRED AMOUNTS MEASURED BY PUTNAM VISTA A ON JULY 31, 2003

Prior to 4 p.m. ET on July 31, 2003, each participant who has any part of
his/her account measured by the Putnam Vista A measurement method may
redesignate the amount in such measurement method in accordance with Article IV.
If a participant does not redesignate the amount measured by the Putnam Vista A
measurement method to any other remaining measurement method before 4 p.m. ET on
July 31, 2003, then the amount in the Putnam Vista A account shall be
redesignated as of 4 p.m. ET on July 31, 2003, to the Fidelity Mid-Cap Stock
Fund.


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                                   SCHEDULE A

                               MEASUREMENT METHODS
                            (EFFECTIVE JULY 31, 2003)

      MERCK COMMON STOCK

      MUTUAL FUNDS

            American Century Emerging Markets Institutional
            American Funds EuroPacific Growth Fund
            Columbia Acorn Class Z*
            Fidelity Destiny I
            Fidelity Dividend Growth
            Fidelity Equity-Income
            Fidelity Low-Priced Stock
            Fidelity Mid-Cap Stock Fund
            Fidelity Retirement Money Market
            Fidelity Spartan Government Income
            Fidelity Spartan U.S. Equity Index
            Franklin Small-Mid Cap Growth A
            Janus Enterprise
            Janus Growth & Income
            PIMCO Foreign Bond Institutional
            PIMCO Long Term US Government Institutional
            PIMCO Total Return Institutional
            Putnam Global Equity A
            Putnam International Capital Opportunities Fund A**
            T. Rowe Price Blue Chip Growth
            Vanguard Asset Allocation

* Prior to October 2003, known as Liberty Acorn Class Z
** Prior to April 30, 2003, known as Putnam International Voyager Fund A


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