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                                                                  EXHIBIT 10.5


                               SECOND AMENDMENT TO

                                 ALLERGAN, INC.

                           SAVINGS AND INVESTMENT PLAN
                                 (RESTATED 1998)

      The ALLERGAN, INC. SAVINGS AND INVESTMENT PLAN (the "Plan") is hereby
amended, effective January 1, 2000, to read as follows:

1.    Section 12.4(b) of the Plan is hereby amended and restated in its entirety
      to read as follows:

            "(b) In the event of a Change in Control (as herein defined), all
      Participants who were Participants on the date of such Change in Control
      shall become 100% vested in any amounts allocated to their Company
      Contribution Accounts on the date of such Change in Control and in any
      amounts allocated to their Company Contribution Accounts subsequent to the
      date of the Change in Control. Notwithstanding the foregoing, the Board of
      Directors may, at its discretion, amend or delete this Paragraph (b) in
      its entirety prior to the occurrence of any such Change in Control. For
      the purpose of this Paragraph (b), "Change in Control" shall mean the
      following and shall be deemed to occur if any of the following events
      occur:

                  (i) Any "person," as such term is used in Sections 13(d) and
            14(d) of the Securities Exchange Act of 1934, as amended (the
            "Exchange Act") (a "Person"), is or becomes the "beneficial owner,"
            as defined in Rule 13d-3 under the Exchange Act (a "Beneficial
            Owner"), directly or indirectly, of securities of Sponsor
            representing (i) 20% or more of the combined voting power of the
            Sponsor's then outstanding voting securities, which acquisition is
            not approved in advance of the acquisition or within 30 days after
            the acquisition by a majority of the Incumbent Board (as hereinafter
            defined) or (ii) 33% or more of the combined voting power of the
            Sponsor's then outstanding voting securities, without regard to
            whether such acquisition is approved by the Incumbent Board;

                  (ii) Individuals who, as of the date hereof, constitute the
            Board of Directors (the "Incumbent Board"), cease for any reason to
            constitute at least a majority of the Board of Directors, provided
            that any person becoming a director subsequent to the date hereof
            whose election, or nomination for election by the Sponsor's
            stockholders, is approved by a vote of at least a majority of the
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            directors then comprising the Incumbent Board (other than an
            election or nomination of an individual whose initial assumption of
            office is in connection with an actual or threatened election
            contest relating to the election of the directors of the Sponsor, as
            such terms are used in Rule 14a-11 of Regulation 14A promulgated
            under the Exchange Act) shall, for the purposes of this Plan, be
            considered as though such person were a member of the Incumbent
            Board of the Sponsor;

                  (iii) The consummation of a merger, consolidation or
            reorganization involving the Sponsor, other than one which satisfies
            both of the following conditions:

                        (A) a merger, consolidation or reorganization which
                  would result in the voting securities of the Sponsor
                  outstanding immediately prior thereto continuing to represent
                  (either by remaining outstanding or by being converted into
                  voting securities of another entity) at least 55% of the
                  combined voting power of the voting securities of the Sponsor
                  or such other entity resulting from the merger, consolidation
                  or reorganization (the "Surviving Corporation") outstanding
                  immediately after such merger, consolidation or reorganization
                  and being held in substantially the same proportion as the
                  ownership in the Sponsor's voting securities immediately
                  before such merger, consolidation or reorganization, and

                        (B) a merger, consolidation or reorganization in which
                  no Person is or becomes the Beneficial Owner, directly or
                  indirectly, of securities of the Sponsor representing 20% or
                  more of the combined voting power of the Sponsor's then
                  outstanding voting securities; or

                  (iv) The stockholders of the Sponsor approve a plan of
            complete liquidation of the Sponsor or an agreement for the sale or
            other disposition by the Sponsor of all or substantially all of the
            Sponsor's assets.

      Notwithstanding the preceding provisions of this Paragraph (b), a Change
      in Control shall not be deemed to have occurred if the Person described in
      the preceding provisions of this Paragraph (b) is (1) an underwriter or
      underwriting syndicate that has acquired any of the Sponsor's then
      outstanding voting securities solely in connection with a public offering
      of the Sponsor's securities, (2) the Sponsor or any subsidiary of the
      Sponsor or (3) an employee stock ownership plan or other employee benefit
      plan maintained by the Company that is qualified under the provisions of
      the

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      Code. In addition, notwithstanding the preceding provisions of this
      Paragraph (b), a Change in Control shall not be deemed to have occurred if
      the Person described in the preceding provisions of this Paragraph (b)
      becomes a Beneficial Owner of more than the permitted amount of
      outstanding securities as a result of the acquisition of voting securities
      by the Company which, by reducing the number of voting securities
      outstanding, increases the proportional number of shares beneficially
      owned by such Person, provided, that if a Change in Control would occur
      but for the operation of this sentence and such Person becomes the
      Beneficial Owner of any additional voting securities (other than through
      the exercise of options granted under any stock option plan of the Sponsor
      or through a stock dividend or stock split), then a Change in Control
      shall occur."

      IN WITNESS WHEREOF, Allergan, Inc. hereby executes this Second Amendment
on the 30th day of December, 1999.

ALLERGAN, INC.

BY: /s/ Francis R. Tunney, Jr.
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    Francis R. Tunney, Jr.,
    Corporate Vice President--Administration,
    General Counsel and Secretary