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                                                                   EXHIBIT 10.18

                                FOURTH AMENDMENT
                                       TO
                                 ALLERGAN, INC.
                       SUPPLEMENTAL EXECUTIVE BENEFIT PLAN
                                 (RESTATED 1996)

      The ALLERGAN, INC. SUPPLEMENTAL EXECUTIVE BENEFIT PLAN (the "Plan") is
hereby amended as follows:

1.    Section 3.5 of the Plan is amended as follows:

            3.5 Claims Procedures. If a person is required by the Committee to
      submit an application for benefits under Section 3.4 or if a Participant
      or his or her beneficiary believes that he or she is being denied any
      rights or benefits under the Plan, the Participant, beneficiary, or in
      either case, his or her authorized representative (the "Claimant") shall
      follow the administrative procedures for filing a claim for benefits as
      set forth in this Section. An application for benefits or a claim for
      benefits shall be in writing and shall be reviewed by the Committee or a
      claims official designated by the Committee. The Committee or claims
      official shall review a claim for benefits in accordance with the
      procedures established by the Committee subject to the following
      administrative procedures set forth in this Section.

                  (a) The Committee shall furnish the Claimant with written or
            electronic notice of the decision rendered with respect to a claim
            for benefits within 90 days following receipt by the Committee (or
            its delegate) of the claim unless the Committee determines that
            special circumstances require an extension of time for processing
            the claim. In the event an extension is necessary, written or
            electronic notice of the extension shall be furnished to the
            Claimant prior to the expiration of the initial 90 day period. The
            notice shall indicate the special circumstances requiring an
            extension of time and the date by which a final decision is expected
            to be rendered. In no event shall the period of the extension exceed
            90 days from the end of the initial 90 day period.

                  (b) In the case of a denial of the Claimant's claim, the
            written or electronic notice of such denial shall set forth (i) the
            specific reasons for the denial, (ii) references to the Plan
            provisions upon which the denial is based, (iii) a description of
            any additional information or material necessary for perfection of
            the claim (together with an explanation why such material or
            information is necessary), (iv) an explanation of the Plan's appeals
            procedures, and (v) a statement of the Claimant's right to bring a
            civil action under Section 502(a) of ERISA if his or her claim is
            denied upon appeal.

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                  (c) In the case of a denial of a claim, a Claimant who wishes
            to appeal the decision shall follow the administrative procedures
            for an appeal as set forth in Section 3.6 below.

      2. The Section 3.6 is amended as follows:

            3.6 Appeals Procedures. A Claimant who wishes to appeal the denial
      of his or her claim for benefits shall follow the administrative
      procedures for an appeal as set forth in this Section and shall exhaust
      such administrative procedures prior to seeking any other form of relief.
      Appeals shall be reviewed in accordance with the procedures established by
      the Committee subject to the following administrative procedures set forth
      in this Section.

                  (a) In order to appeal a decision rendered with respect to his
            or her claim for benefits, a Claimant must file an appeal with the
            Committee in writing within 60 days following his or her receipt of
            the notice of denial with respect to the claim.

                  (b) The Claimant's appeal may include written comments,
            documents, records and other information relating to his or her
            claim. The Claimant may review all pertinent documents and, upon
            request, shall have reasonable access to or be provided free of
            charge, copies of all documents, records, and other information
            relevant to his or her claim.

                  (c) The Committee shall provide a full and fair review of the
            appeal and shall take into account all claim related comments,
            documents, records, and other information submitted by the Claimant
            without regard to whether such information was submitted or
            considered under the initial determination or review of the initial
            determination. Where appropriate, the Committee will overturn a
            notice of denial if it determines that an error was made in the
            interpretation of the controlling plan documents or if the Committee
            determines that an existing interpretation of the controlling plan
            documents should be changed on a prospective basis. In the event the
            Claimant is a subordinate, as determined by the Committee, to an
            individual conducting the review, such individual shall recuse
            himself or herself from the review of the appeal.

                  (d) The Committee shall furnish the Claimant with written or
            electronic notice of the decision rendered with respect to an appeal
            within 60 days following receipt by the Committee of the appeal
            unless the Committee determines that special circumstances require
            an extension of time for processing the appeal. In the event an
            extension is necessary, written or electronic notice of the
            extension shall be furnished to the Claimant prior to the expiration
            of the initial 60 day period. The notice shall indicate the special
            circumstances requiring an extension of time and the date by which a
            final decision is expected to be rendered. In no event


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            shall the period of the extension exceed 60 days from the end of the
            initial 60 day period.

                  (e) In the case of a denial of an appeal, the written or
            electronic notice of such denial shall set forth (i) the specific
            reasons for the denial, (ii) references to the Plan provisions upon
            which the denial is based, (iii) a statement that the Claimant is
            entitled to receive, upon request and free of charge, reasonable
            access to, and copies of, all documents, records, and other
            information relating to his or her claim for benefits, and (iv) a
            statement of the Claimant's right to bring a civil action under
            Section 502(a) of ERISA.

      IN WITNESS WHEREOF, Allergan, Inc. hereby executes this Fourth Amendment
to the Allergan, Inc. Supplemental Executive Benefit Plan on this 18th day of
December, 2002.

ALLERGAN, INC.


By: /s/ Douglas Ingram
    -------------------------------------------------------
    Douglas Ingram
    Corporate Vice President, General Counsel and Secretary


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