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                                                                     Exhibit 4.3

                                 ALLERGAN, INC.

                     1.50% Convertible Senior Notes Due 2026

                          REGISTRATION RIGHTS AGREEMENT

                                                              New York, New York
                                                                  April 12, 2006

Banc of America Securities LLC
Citigroup Global Markets Inc.
Morgan Stanley & Co. Incorporated
   As Representatives of the Initial Purchasers
c/o Citigroup Global Markets Inc.
388 Greenwich Street
New York, New York 10013

Ladies and Gentlemen:

          Allergan, Inc., a corporation organized under the laws of the State of
Delaware (the "Company"), proposes to issue and sell to certain purchasers (the
"Initial Purchasers"), for whom you (the "Representatives") are acting as
representatives, its 1.50% Convertible Senior Notes Due 2026 (the "Notes"), upon
the terms set forth in the Purchase Agreement between the Company and the
Initial Purchasers dated April 6, 2006 (the "Purchase Agreement") relating to
the initial placement (the "Initial Placement") of the Notes. The Notes will be
convertible into Shares (as defined herein), on the terms and subject to the
conditions set forth in the Indenture (as defined herein). To induce the Initial
Purchasers to enter into the Purchase Agreement and to satisfy a condition to
your obligations thereunder, the Company agrees with you for your benefit and
the benefit of the holders from time to time of the Securities (including the
Initial Purchasers) (each a "Holder" and, collectively, the "Holders"), as
follows:

          1. Definitions. Capitalized terms used herein without definition shall
have their respective meanings set forth in the Purchase Agreement. As used in
this Agreement, the following capitalized defined terms shall have the following
meanings:

          "Act" shall mean the Securities Act of 1933, as amended, and the rules
and regulations of the Commission promulgated thereunder.

          "Affiliate" shall have the meaning specified in Rule 405 under the Act
and the terms "controlling" and "controlled" shall have meanings correlative
thereto.

          "Amendment Effectiveness Deadline Date" shall mean the date that is 45
days after the date such post-effective amendment is required by Section 2(h)(i)
to be filed.

          "Broker-Dealer" shall mean any broker or dealer registered as such
under the Exchange Act.

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          "Business Day" shall mean any day other than a Saturday, a Sunday or a
legal holiday or a day on which banking institutions or trust companies are
authorized or obligated by law to close in New York City.

          "Closing Date" shall mean the date of first issuance of the Notes.

          "Commission" shall mean the Securities and Exchange Commission.

          "Common Stock" shall mean the common stock of the Company, par value
$0.01 per share, as it exists on the date of the Indenture and any other shares
of capital stock or other securities of the Company into which such Common Stock
may be reclassified or changed, together with any and all other securities which
may from time to time be issuable upon conversion of Notes.

          "Conversion Rate" shall have the meaning indicated in the Indenture.

          "Deferral Notice" shall have the meaning indicated in Section
3(c)(x)(B) hereof.

          "Deferral Period" shall have the meaning indicated in Section
3(c)(x)(B) hereof.

          "Effectiveness Date" shall mean the date of effectiveness or
availability of the Shelf Registration Statement.

          "Effectiveness Target Date" shall mean no later than 180 days after
the date hereof.

          "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the Commission promulgated thereunder.

          "Final Memorandum" shall mean the offering memorandum, dated April 6,
2006, relating to the Notes, including any and all exhibits thereto and any
information incorporated by reference therein as of such date.

          "Holder" shall have the meaning set forth in the preamble hereto.

          "Indenture" shall mean the Indenture relating to the Securities, dated
as of April 12, 2006, between the Company and Wells Fargo Bank, National
Association, as trustee, as the same may be amended from time to time in
accordance with the terms thereof.

          "Initial Placement" shall have the meaning set forth in the preamble
hereto.

          "Initial Purchaser" shall have the meaning set forth in the preamble
hereto.

          "Issuer Free Writing Prospectus" shall mean an issuer free writing
prospectus, as defined in Rule 433 under the Act.

          "Losses" shall have the meaning set forth in Section 6(d) hereof.


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          "Majority Holders" shall mean, on any date, Holders of a majority of
the aggregate principal amount of Securities registered under a Registration
Statement, provided that Holders of Shares issued upon conversion of Notes shall
not be deemed Holders of Shares, but shall be deemed Holders of the aggregate
principal amount of the Notes from which such Shares were converted.

          "NASD Rules" shall mean the Conduct Rules and the By-Laws of the
National Association of Securities Dealers, Inc.

          "Notes" shall have the meaning indicated in the preamble hereto.

          "Notice and Questionnaire" shall mean a written notice delivered to
the Company substantially in the form attached as Annex A to the Final
Memorandum.

          "Notice Holder" shall mean, on any date, any Holder of Registrable
Securities that has delivered a Notice and Questionnaire to the Company on or
prior to such date.

          "Prospectus" shall mean a prospectus included in the Shelf
Registration Statement (including, without limitation, a prospectus that
discloses information previously omitted from a prospectus filed as part of an
effective registration statement in reliance upon Rule 430A under the Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Securities covered by the Shelf
Registration Statement, and all amendments and supplements thereto, including
any and all exhibits thereto and any information incorporated by reference
therein.

          "Purchase Agreement" shall have the meaning indicated in the preamble
hereto.

          "Registrable Securities" shall mean each Note (each a "Registrable
Note") and each share of Common Stock issued upon conversion of Notes other than
those that have been (A) registered under a Registration Statement and disposed
of in accordance therewith or (B) distributed to the public pursuant to Rule 144
under the Act or any successor rule or regulation thereto that may be adopted by
the Commission.

          "Registration Default Damages" shall have the meaning set forth in
Section 8 hereof.

          "Securities" shall mean, collectively, the Notes and the Shares.

          "Shares" means the shares of Common Stock into which the Notes are
convertible or that have been issued upon any conversion from Notes into Common
Stock.

          "Shelf Filing Deadline" shall mean 120 days after the Closing Date.

          "Shelf Registration Period" from the date the Shelf Registration
Statement becomes effective until the date that the Notes and the shares of
Common Stock issuable upon exchange thereof have ceased to be Registrable
Securities.


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          "Shelf Registration Statement" shall mean a "shelf" registration
statement of the Company pursuant to the provisions of Section 2 hereof which
covers some or all of the Securities on an appropriate form under Rule 415 under
the Act, or any similar rule that may be adopted by the Commission, amendments
and supplements to such registration statement, including post-effective
amendments, in each case including the Prospectus contained therein, all
exhibits thereto and all material incorporated by reference therein.

          "Trustee" shall mean the trustee with respect to the Securities under
the Indenture.

          "Trust Indenture Act" shall mean the Trust Indenture Act of 1939, as
amended, and the rules and regulations of the Commission promulgated thereunder.

          2. Shelf Registration. (a) The Company shall as promptly as
practicable (but in no event after the Shelf Filing Deadline) cause to be filed,
or otherwise designate an existing filing with the Commission as a Shelf
Registration Statement, providing for the registration of, and the sale on a
continuous or delayed basis by the Holders of, all of the Registrable
Securities, from time to time in accordance with the methods of distribution
elected by such Holders, pursuant to Rule 415 under the Act or any similar rule
that may be adopted by the Commission, subject to the terms and conditions
hereof;

          (b) The Company shall use its reasonable best efforts to cause the
Shelf Registration Statement to become effective under the Act, or otherwise
make available for use by Holders a previously filed Shelf Registration
Statement, no later than the Effectiveness Target Date and the Effectiveness
Date;

          (c) The Company shall use its reasonable best efforts to keep the
Shelf Registration Statement continuously effective, supplemented and amended as
required by the Act, in order to permit the Prospectus forming part thereof to
be usable by Holders for a period (the "Shelf Registration Period") from the
date the Shelf Registration Statement is declared effective by the Commission
until the earlier of: (A) two years after the last date of the original issuance
of any of the Notes, (B) the sale pursuant to the Shelf Registration Statement
of all the Notes or the shares of Common Stock issuable upon conversion of the
Notes and (C) the date when the Holders of the Notes and the Common Stock
issuable upon conversion thereof are able to sell all such securities
immediately without restriction pursuant to the volume limitation provisions of
Rule 144 under the Securities Act.

          The Company shall be deemed not to have used its reasonable best
efforts to keep the Shelf Registration Statement effective during the Shelf
Registration Period if it voluntarily takes any action that would result in
Holders of Registrable Securities not being able to offer and sell such
Securities at any time during the Shelf Registration Period, unless such action
is (x) required by applicable law or otherwise undertaken by the Company in good
faith and for valid business reasons (not including avoidance of the Company's
obligations hereunder), including the acquisition or divestiture of assets, and
(y) permitted by Section 3(c)(x)(B) hereof.

          (d) The Company shall cause the Shelf Registration Statement and the
related Prospectus and any amendment or supplement thereto, as of the effective
date of the Shelf Registration Statement or such amendment or supplement, and
any Issuer Free Writing


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Prospectus, as of the date thereof, (i) to comply in all material respects with
the applicable requirements of the Act; and (ii) not to contain any untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary in order to make the statements therein (in the case
of the Prospectus and any Issuer Free Writing Prospectus, in the light of the
circumstances under which they were made) not misleading.

          (e) Not less than 30 days prior to the Effectiveness Target Date, the
Company shall mail the Notice and Questionnaire to the Holders. Each Holder that
becomes a Notice Holder (and provides such additional information as the Company
reasonably may request) no later than 15 days following such Holder's receipt of
notice from the Company of the filing or designation of the Shelf Registration
Statement shall be named as a selling securityholder in the initial Registration
Statement made available to Holders under the Shelf Registration Statement.

          (f) If the Shelf Registration Statement ceases to be effective for any
reason at any time during the Shelf Registration Period (other than because all
Registrable Securities registered thereunder shall have been resold pursuant
thereto or shall have otherwise ceased to be Registrable Securities), the
Company shall use its reasonable best efforts to obtain the prompt withdrawal of
any order suspending the effectiveness thereof or file or designate a subsequent
Shelf Registration Statement covering all of the securities that as of the date
of such filing or designation are Registrable Securities. If such an subsequent
Shelf Registration Statement is filed or designated (and is not already
effective), the Company shall use its reasonable best efforts to cause the
subsequent Shelf Registration Statement to become effective as promptly as is
practicable after such filing or designation and to keep such subsequent Shelf
Registration Statement continuously effective until the end of the Shelf
Registration Period.

          (g) The Company shall supplement and amend the Shelf Registration
Statement if required by the rules, regulations or instructions applicable to
the registration form used by the Company for such Shelf Registration Statement,
if required by the Act or as reasonably requested by the Initial Purchasers or
by the Trustee on behalf of the Holders of the Registrable Securities covered by
such Shelf Registration Statement.

          (h) Each Holder of Registrable Securities agrees to deliver a Notice
and Questionnaire to the Company at least five Business Days prior to any
intended distribution by it of Registrable Securities under the Shelf
Registration Statement. From and after the Effectiveness Date, the Company
shall, as promptly as practicable after the date a Notice and Questionnaire is
delivered, and in any event upon the later of (x) ten Business Days after such
date (but no earlier than ten Business Days after effectiveness) or (y) ten
Business Days after the expiration of any Deferral Period in effect when the
Notice and Questionnaire is delivered or put into effect within five Business
Days of such delivery date:

               (i) if required by applicable law, file with the Commission a
          post-effective amendment to the Shelf Registration Statement or
          prepare and, if required by applicable law, file a supplement to the
          related Prospectus or an amendment or supplement to any document
          incorporated therein by reference or file any other required document
          so that the Holder delivering such Notice and Questionnaire is named
          as a selling securityholder in the Shelf Registration Statement and
          the related Prospectus in such a manner as to permit such Holder to


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          deliver such Prospectus to purchasers of the Registrable Securities in
          accordance with applicable law and, if the Company shall file a
          post-effective amendment to the Shelf Registration Statement, use its
          reasonable best efforts to cause such post-effective amendment to
          become effective under the Act as promptly as is practicable, but in
          any event by the Amendment Effectiveness Deadline Date;

               (ii) provide such Holder copies of any documents filed pursuant
          to Section 2(g)(i); and

               (iii) notify such Holder as promptly as practicable after the
          effectiveness under the Act of any post-effective amendment filed
          pursuant to Section 2(g)(i);

provided that if such Notice and Questionnaire is delivered during a Deferral
Period, the Company shall so inform the Holder delivering such Notice and
Questionnaire and shall take the actions set forth in clauses (i), (ii) and
(iii) above upon expiration of the Deferral Period in accordance with Section
2(c). Notwithstanding anything contained herein to the contrary, (i) the Company
shall be under no obligation to name any Holder that is not a Notice Holder as a
selling securityholder in any Registration Statement or related Prospectus and
(ii) the Amendment Effectiveness Deadline Date shall be extended by up to 20
Business Days from the Expiration of a Deferral Period if such Deferral Period
shall be in effect on the Amendment Effectiveness Deadline Date.

          3. Registration Procedures. The following provisions shall apply in
connection with the Shelf Registration Statement.

          (a) the Company shall:

               (i) comply with all the provisions of Section 2(c) hereof and
          shall use its reasonable best efforts to effect such registration to
          permit the sale of the Registrable Securities, and pursuant thereto,
          shall as expeditiously as possible prepare and file with the
          Commission a Shelf Registration Statement relating to the registration
          on any appropriate form under the Act, or otherwise make available for
          use by Holders a previously filed Shelf Registration Statement.

               (ii) furnish to each of the Representatives and to counsel for
          the Notice Holders, not less than five Business Days prior to the
          filing thereof with the Commission, a copy of the Shelf Registration
          Statement and each amendment thereof and each amendment or supplement,
          if any, to the Prospectus included therein (including all documents
          incorporated by reference therein after the initial filing) and shall
          use its reasonable best efforts to reflect in each such document, when
          so filed with the Commission, such comments as the Representatives
          reasonably propose; and

               (iii) include information regarding the Notice Holders and the
          methods of distribution they have elected for their Registrable
          Securities provided to the Company in Notices and Questionnaires as
          necessary to permit such distribution by the methods specified
          therein.


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          (b) The Company shall ensure that:

               (i) the Shelf Registration Statement and any amendment thereto
          and any Prospectus forming part thereof and any amendment or
          supplement thereto complies in all material respects with the Act; and

               (ii) the Shelf Registration Statement and any amendment thereto
          does not, when it becomes effective, contain an untrue statement of a
          material fact or omit to state a material fact required to be stated
          therein or necessary to make the statements therein not misleading.

          (c) in connection with the Shelf Registration Statement and any
Prospectus required by this Agreement to permit the sale or resale of
Registrable Securities, the Company shall:

               (i) subject to any notice by the Company in accordance with this
          Section 3(c) of the existence of any fact or event of the kind
          described in Section 3(c)(iii)(D), use its reasonable best efforts to
          keep the Shelf Registration Statement continuously effective during
          the Shelf Registration Period; upon the occurrence of any event that
          would cause the Shelf Registration Statement or the Prospectus
          contained therein (A) to contain a material misstatement or omission
          or (B) not to be effective and usable for resale of Registrable
          Securities during the Shelf Registration Period, the Company shall
          file promptly a post-effective amendment to the Shelf Registration
          Statement or an amendment or supplement to the related Prospectus or
          file any other required document, in the case of clause (A),
          correcting any such misstatement or omission, and, in the case of
          either clause (A) or (B), use its reasonable best efforts to cause any
          such amendment to become effective and the Shelf Registration
          Statement and the related Prospectus to become usable for their
          intended purposes as soon as practicable thereafter.

               (ii) prepare and file with the Commission such amendments and
          post-effective amendments to the Shelf Registration Statement as may
          be necessary to keep the Shelf Registration Statement effective during
          the Shelf Registration Period; cause the Prospectus to be supplemented
          by any required Prospectus supplement, and as so supplemented to be
          filed pursuant to Rule 424 under the Act, and to comply fully with the
          applicable provisions of Rule 424 under the Act in a timely manner;
          and comply with the provisions of the Act with respect to the
          disposition of all Registrable Securities covered by the Shelf
          Registration Statement during the applicable period in accordance with
          the intended method or methods of distribution by the sellers thereof
          set forth or to be set forth in the Shelf Registration Statement or
          supplement to the Prospectus.

               (iii) advise the Initial Purchasers and selling Holders promptly
          and, if requested, to confirm such advice in writing (which notice
          pursuant to clauses (B) through (E) below shall be accompanied by an
          instruction to suspend the use of the Prospectus until the Company
          shall have remedied the basis for such suspension):


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                    (A) when the Prospectus, any Prospectus supplement, any
               post-effective amendment or any Issuer Free Writing Prospectus
               has been filed with the Commission, and when the Shelf
               Registration Statement or any post-effective amendment thereto
               has become effective,

                    (B) of any request by the Commission for any amendment or
               supplement to the Shelf Registration Statement, the Prospectus or
               any Issuer Free Writing Prospectus or for additional information,

                    (C) of the issuance by the Commission of any stop order
               suspending the effectiveness of the Shelf Registration Statement
               under the Act or of any notice that would prevent its use, or the
               institution or threatening of any proceeding for any of the
               preceding purposes,

                    (D) of the receipt by the Company of any notification with
               respect to the suspension of the qualification of the Registrable
               Securities for offering or sale in any jurisdiction, or the
               threatening or initiation of any proceeding for any of the
               preceding purposes,

                    (E) of the existence of any fact or the happening of any
               event, during the Shelf Registration Period, that makes any
               statement of a material fact made in the Shelf Registration
               Statement, the Prospectus, any amendment or supplement thereto,
               or any document incorporated by reference therein untrue, or that
               requires the making of any additions to or changes in the Shelf
               Registration Statement or the Prospectus in order to make the
               statements therein (in the case of the Prospectus, in the light
               of the circumstances under which they were made) not misleading,
               or

                    (F) when any Issuer Free Writing Prospectus includes
               information that may conflict with the information contained in
               the Registration Statement.

               (iv) use its reasonable best efforts to prevent the issuance of
          any order suspending the effectiveness of the Shelf Registration
          Statement or the qualification of the securities therein for sale in
          any jurisdiction or any notice that would prevent its use and, if
          issued, to obtain as soon as possible the withdrawal thereof.

               (v) furnish to each Notice Holder, without charge, at least one
          copy of the Shelf Registration Statement and any post-effective
          amendment thereto, including all material incorporated therein by
          reference, and, if a Notice Holder so requests in writing, all
          exhibits thereto (including exhibits incorporated by reference
          therein).

               (vi) if requested by any selling Holders or the Representatives,
          promptly incorporate in the Shelf Registration Statement or
          Prospectus, pursuant to a supplement or post-effective amendment if
          necessary, such information as such selling Holders may reasonably
          request to have included therein, including,


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          without limitation, information relating to the "Plan of Distribution"
          of the Registrable Securities.

               (vii) deliver to each Initial Purchaser, selling Holder, and any
          sales or placement agents or underwriters acting on their behalf,
          without charge, as many copies of the Prospectus (including each
          preliminary Prospectus) and any amendment or supplement thereto, and
          any Issuer Free Writing Prospectus, as such persons may reasonably
          request. The Company hereby consents to the use of the Prospectus and
          any amendment or supplement thereto, and any Issuer Free Writing
          Prospectus, by each of the selling Holders in connection with the
          offering and sale of the Registrable Securities covered by the
          Prospectus or any amendment or supplement thereto.

               (viii) prior to any public offering of Registrable Securities,
          arrange, if necessary, for the qualification of the Securities for
          sale under the laws of such jurisdictions as any Holder shall
          reasonably request and shall maintain such qualification in effect so
          long as required; provided that in no event shall the Company be
          obligated to qualify to do business in any jurisdiction where it is
          not then so qualified or to take any action that would subject it to
          service of process in suits, other than those arising out of the
          Initial Placement or any offering pursuant to the Shelf Registration
          Statement, in any such jurisdiction where it is not then so subject.

               (ix) cooperate with the Holders of Securities to facilitate the
          timely preparation and delivery of certificates representing
          Securities to be issued or sold pursuant to the Shelf Registration
          Statement free of any restrictive legends and in such denominations
          and registered in such names as Holders may request.

               (x) (A) Upon the occurrence of any event contemplated by
          subsections (c)(iii)(B) through (D) above, the Company shall promptly
          (or within the time period provided for by clause (B) hereof, if
          applicable) prepare a post-effective amendment to the applicable
          Registration Statement or an amendment or supplement to the related
          Prospectus, relevant Issuer Free Writing Prospectus or any document
          incorporated therein by reference or file any other required document
          so that, as thereafter delivered to purchasers of the securities
          included therein, such Registration Statement, Prospectus or Issuer
          Free Writing Prospectus will not include an untrue statement of a
          material fact or omit to state any material fact required to be stated
          therein or necessary to make the statements therein, in the light of
          the circumstances under which they were made, not misleading.

                    (B) Upon the occurrence or existence of any pending
               corporate development or any other material event that, in the
               reasonable judgment of the Company, makes it appropriate to
               suspend the availability of the Shelf Registration Statement and
               the related Prospectus or relevant Issuer Free Writing
               Prospectus, the Company shall give notice (without notice of the
               nature or details of such events) (a "Deferral Notice") to the
               Holders


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               that the availability of the Shelf Registration Statement is
               suspended and, upon actual receipt of any such notice, each
               Holder agrees not to sell any Registrable Securities pursuant to
               the Shelf Registration until such Holder's receipt of copies of
               the supplemented or amended Prospectus provided for in Section
               3(c)(xi) hereof, or until it is advised in writing by the Company
               that the Prospectus and any applicable Issuer Free Writing
               Prospectus may be used, and has received copies of any additional
               or supplemental filings that are incorporated or deemed
               incorporated by reference in such Prospectus or Issuer Free
               Writing Prospectus. The period during which the availability of
               the Shelf Registration, any Prospectus or any Issuer Free Writing
               Prospectus is suspended (the "Deferral Period") shall not exceed
               120 days in any twelve-month period.

               (xi) not later than the effective date of the Shelf Registration
          Statement, provide CUSIP numbers for the Securities registered under
          the Shelf Registration Statement and provide the Trustee with printed
          certificates for such Securities, in a form eligible for deposit with
          The Depository Trust Company.

               (xii) comply with all applicable rules and regulations of the
          Commission and shall make generally available to its security holders
          an earnings statement satisfying the provisions of Section 11(a) of
          the Act as soon as practicable after the effective date of the Shelf
          Registration Statement and in any event no later than 40 days after
          the end of a 12-month period (or 75 days, if such period is a fiscal
          year) beginning with the first month of the Company's first fiscal
          quarter commencing after the effective date of the Shelf Registration
          Statement.

               (xiii) cause the Indenture to be qualified under the Trust
          Indenture Act in a timely manner.

               (xiv) enter into customary agreements and take all other
          appropriate actions in order to expedite or facilitate the
          registration or the disposition of the Securities.

               (xv) make reasonably available for inspection by the Holders of
          Securities to be registered thereunder, and any attorney, accountant
          or other agent retained by the Holders or any such underwriter all
          relevant financial and other records and pertinent corporate documents
          of the Company and its subsidiaries.

               (xvi) cause the Company's officers, directors, employees,
          accountants and auditors to supply all relevant information reasonably
          requested by the Holders or any such attorney, accountant or agent in
          connection with the Shelf Registration Statement as is customary for
          similar due diligence examinations.

               (xvii) cause all Common Stock covered by the Shelf Registration
          Statement to be listed or quoted, as the case may be, on each
          securities exchange or automated quotation system on which Common
          Stock is then listed or quoted.


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               (xviii) provide to each Holder upon written request each document
          filed with the Commission pursuant to the requirements of Section 13
          and Section 15 of the Exchange Act after the effective date of the
          Shelf Registration Statement, unless such document is available
          through the Commission's EDGAR system.

               (xix) use its reasonable best efforts if the Securities have been
          rated prior to the initial sale of such Securities, to confirm such
          ratings will apply to the Securities covered by the Shelf Registration
          Statement.

               (xx) use its reasonable best efforts to take all other steps
          necessary to effect the registration of the Registrable Securities
          covered by the Shelf Registration Statement.

          (d) The Company may require each Holder of securities to be sold
pursuant to any Shelf Registration Statement to furnish to the Company such
information regarding the Holder and the distribution of such securities as the
Company may from time to time reasonably require for inclusion in such
Registration Statement. The Company may exclude from such Shelf Registration
Statement the Securities of any Holder that unreasonably fails to furnish such
information within a reasonable time after receiving such request.

          (e) In the event that any Broker-Dealer shall underwrite any
Securities or participate as a member of an underwriting syndicate or selling
group or "assist in the distribution" (within the meaning of the NASD Rules)
thereof, whether as a Holder of such Securities or as an underwriter, a
placement or sales agent or a broker or dealer in respect thereof, or otherwise,
the Company shall assist such Broker-Dealer in complying with the NASD Rules.

          (f) The Company shall use its reasonable best efforts to take all
other steps necessary to effect the registration of the Securities covered by
the Shelf Registration Statement.

          4. Holder's Obligations: Each Holder agrees, by acquisition of the
Registrable Securities, that no Holder of Registrable Securities shall be
entitled to sell any of such Registrable Securities pursuant to a Registration
Statement or to receive a Prospectus relating thereto, unless such Holder has
furnished the Company with a Notice and Questionnaire as required pursuant to
Section 2(d) and 2(g) hereof (including the information required to be included
in such Notice and Questionnaire) and the information set forth in the next
sentence. Each Notice Holder agrees promptly to furnish to the Company all
information required to be disclosed in order to make the information previously
furnished to the Company by such Notice Holder not misleading and any other
information regarding such Notice Holder and the distribution of such
Registrable Securities as the Company may from time to time reasonably request.
Any sale of any Registrable Securities by any Holder shall constitute a
representation and warranty by such Holder that the information relating to such
Holder and its plan of distribution is as set forth in the Prospectus delivered
by such Holder in connection with such distribution, that such Prospectus does
not as of the time of such sale contain any untrue statement of a material fact
relating to or provided by such Holder or its plan of distribution and that such
Prospectus does not as of the time of such sale omit to state any material fact
relating to


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or provided by such Holder or its plan of distribution necessary to make the
statements in such Prospectus, in light of the circumstances under which they
were made, not misleading.

          5. Registration Expenses. The Company shall bear all expenses incurred
in connection with the performance of its obligations hereunder and will
reimburse the Holders for the reasonable fees and disbursements of one firm or
counsel (which shall initially be Cleary Gottlieb Steen & Hamilton LLP, but
which may be another nationally recognized law firm experienced in securities
matters designated by the Majority Holders) to act as counsel for the Holders in
connection herewith.

          6. Indemnification and Contribution. (a) The Company agrees to
indemnify and hold harmless each Holder of Securities covered by the Shelf
Registration Statement, each Initial Purchaser and each person who controls any
such Holder or Initial Purchaser within the meaning of either the Act or the
Exchange Act against any and all losses, claims, damages or liabilities, joint
or several, to which they or any of them may become subject under the Act, the
Exchange Act or other federal or state statutory law or regulation, at common
law or otherwise, insofar as such losses, claims, damages or liabilities (or
actions in respect thereof) arise out of or are based upon any untrue statement
or alleged untrue statement of a material fact contained in the Shelf
Registration Statement as originally filed or in any amendment thereof, or in
any Issuer Free Writing Prospectus, any preliminary Prospectus or the
Prospectus, or in any amendment thereof or supplement thereto, or arise out of
or are based upon the omission or alleged omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
(in the case of any Issuer Free Writing Prospectus, any preliminary Prospectus
or the Prospectus, in the light of the circumstances under which they were made)
not misleading, and agrees to reimburse each such indemnified party, as
incurred, for any legal or other expenses reasonably incurred by it in
connection with investigating or defending any such loss, claim, damage,
liability or action; provided, however, that the Company will not be liable in
any such case to the extent that any such loss, claim, damage or liability
arises out of or is based upon any such untrue statement or alleged untrue
statement or omission or alleged omission made therein in reliance upon and in
conformity with written information furnished to the Company by or on behalf of
the party claiming indemnification specifically for inclusion therein and
provided further, that the Company will not be liable in any such case to the
extent that a Holder fails to deliver, at or prior to the written confirmation
of sale, the most recent Prospectus, as amended or supplemented, if such
Prospectus, as amended or supplemented, had been previously furnished by or on
behalf of the Company to such Holder and corrected such untrue statement or
omission or alleged untrue statement or omission of a material fact and the
delivery thereof by such Holder was required by law or any rule or regulation of
any applicable stock exchange. This indemnity agreement shall be in addition to
any liability that the Company may otherwise have.

          (b) Each Holder of Securities covered by the Shelf Registration
Statement (including each Initial Purchaser that is a Holder, in such capacity)
severally and not jointly agrees to indemnify and hold harmless the Company,
each of its directors, each of its officers who signs the Shelf Registration
Statement and each person who controls the Company within the meaning of either
the Act or the Exchange Act, to the same extent as the foregoing indemnity from
the Company to each such Holder, against any and all losses, claims, damages or
liabilities, joint or several, to which the Company or such control persons may
become subject under the Act, the Exchange Act or other federal or state
statutory law or regulation, at common law or


                                       12

<PAGE>

otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of a material fact contained in the Shelf Registration
Statement as originally filed or in any amendment thereof, or in any Issuer Free
Writing Prospectus, any preliminary Prospectus or the Prospectus, or in any
amendment thereof or supplement thereto, or arise out of or are based upon the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein (in the case of any
Issuer Free Writing Prospectus, any preliminary Prospectus or the Prospectus, in
light of the circumstances under which they were made) not misleading, and
agrees to reimburse each such indemnified party, as incurred, for any legal or
other expenses reasonably incurred by it in connection with investigating or
defending any such loss, claim, damage, liability or action, but in each case
only to the extent that the untrue statement or omission or alleged untrue
statement or omission was made in reliance upon and in conformity with written
information relating to such Holder furnished to the Company by or on behalf of
such Holder specifically for inclusion in the documents referred to in the
foregoing indemnity. This indemnity agreement shall be acknowledged by each
Notice Holder that is not an Initial Purchaser in such Notice Holder's Notice
and Questionnaire and shall be in addition to any liability that any such Notice
Holder may otherwise have.

          (c) Promptly after receipt by an indemnified party under this Section
6 or notice of the commencement of any action, such indemnified party will, if a
claim in respect thereof is to be made against the indemnifying party under this
Section 6, notify the indemnifying party in writing of the commencement thereof;
but the failure so to notify the indemnifying party (i) will not relieve it from
liability under paragraph (a) or (b) above unless and to the extent it did not
otherwise learn of such action and such failure results in the forfeiture by the
indemnifying party of substantial rights and defenses; and (ii) will not, in any
event, relieve the indemnifying party from any obligations to any indemnified
party other than the indemnification obligation provided in paragraph (a) or (b)
above. The indemnifying party shall be entitled to appoint counsel (including
local counsel) of the indemnifying party's choice at the indemnifying party's
expense to represent the indemnified party in any action for which
indemnification is sought (in which case the indemnifying party shall not
thereafter be responsible for the fees and expenses of any separate counsel,
other than local counsel if not appointed by the indemnifying party, retained by
the indemnified party or parties except as set forth below); provided however,
that such counsel shall be satisfactory to the indemnified party. It is
understood that the indemnifying party shall not, in respect of the legal
expenses of any indemnified party in connection with any proceeding or related
proceedings in the same jurisdiction, be liable for the fees and expenses of
more than one separate firm (in addition to any local counsel) for all such
indemnified parties. Notwithstanding the indemnifying party's election to
appoint counsel (including local counsel) to represent the indemnified party in
an action, the indemnified party shall have the right to employ separate counsel
(including local counsel), and the indemnifying party shall bear the reasonable
fees, costs and expenses of such separate counsel if (i) the use of counsel
chosen by the indemnifying party to represent the indemnified party would
present such counsel with a conflict of interest; (ii) the actual or potential
defendants in, or targets of, any such action include both the indemnified party
and the indemnifying party and the indemnified party shall have reasonably
concluded that there may be legal defenses available to it and/or other
indemnified parties that are different from or additional to those available to
the indemnifying party; (iii) the indemnifying party shall not have employed
counsel satisfactory to the indemnified party to represent the indemnified party
within a


                                       13

<PAGE>

reasonable time after notice of the institution of such action; or (iv) the
indemnifying party shall authorize the indemnified party to employ separate
counsel at the expense of the indemnifying party. An indemnifying party will
not, without the prior written consent of the indemnified parties, settle or
compromise or consent to the entry of any judgment with respect to any pending
or threatened claim, action, suit or proceeding in respect of which
indemnification or contribution may be sought hereunder (whether or not the
indemnified parties are actual or potential parties to such claim or action)
unless such settlement, compromise or consent includes an unconditional release
of each indemnified party from all liability arising out of such claim, action,
suit or proceeding.

          (d) In the event that the indemnity provided in paragraph (a) or (b)
of this Section 6 is unavailable to or insufficient to hold harmless an
indemnified party for any reason, then each applicable indemnifying party shall
have a joint and several obligation to contribute to the aggregate losses,
claims, damages and liabilities (including legal or other expenses reasonably
incurred in connection with investigating or defending loss, claim, liability,
damage or action) (collectively "Losses") to which such indemnified party may be
subject in such proportion as is appropriate to reflect the relative benefits
received by such indemnifying party, on the one hand, and such indemnified
party, on the other hand, from the Initial Placement and the Shelf Registration
Statement which resulted in such Losses; provided, however, that in no event
shall any Initial Purchaser be responsible, in the aggregate, for any amount in
excess of the purchase discount or commission applicable to such Security, as
set forth in the Final Memorandum; provided further, that in no event shall the
Company be responsible, in the aggregate, for any amount in excess of the total
net proceeds from the initial placement pursuant to the Purchase Agreement
(before deducting expenses) of the Registrable Securities to which such Losses
relate; provided further, that in no event shall any Holder be responsible, in
the aggregate, for any amount in excess of the amount by which (i) the total
price at which the Notes purchased by it were resold exceeds (ii) the amount of
any damages which such Holder has otherwise been required to pay by reason of
any untrue or alleged untrue statement or omission or alleged omission. If the
allocation provided by the immediately preceding sentence is unavailable for any
reason, the indemnifying party and the indemnified party shall contribute in
such proportion as is appropriate to reflect not only such relative benefits but
also the relative fault of such indemnifying party, on the one hand, and such
indemnified party, on the other hand, in connection with the statements or
omissions which resulted in such Losses as well as any other relevant equitable
considerations. Benefits received by the Company shall be deemed to be equal to
the total net proceeds from the Initial Placement (before deducting expenses) as
set forth in the Final Memorandum. Benefits received by the Initial Purchasers
shall be deemed to be equal to the total purchase discounts and commissions as
set forth on the cover page of the Final Memorandum, and benefits received by
any other Holders shall be deemed to be equal to the value of receiving
Securities registered under the Act. Relative fault shall be determined by
reference to, among other things, whether any untrue or any alleged untrue
statement of a material fact or omission or alleged omission to state a material
fact relates to information provided by the indemnifying party, on the one hand,
or by the indemnified party, on the other hand, the intent of the parties and
their relative knowledge, access to information and opportunity to correct or
prevent such untrue statement or omission. The parties agree that it would not
be just and equitable if contribution were determined by pro rata allocation
(even if the Holders were treated as one entity for such purpose) or any other
method of allocation which does not take account of the equitable considerations
referred to above. Notwithstanding the provisions of


                                       14

<PAGE>

this paragraph (d), no person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation. For purposes of
this Section 6, each person who controls a Holder within the meaning of either
the Act or the Exchange Act and each director and officer of such Holder shall
have the same rights to contribution as such Holder, and each person who
controls the Company within the meaning of either the Act or the Exchange Act,
each officer of the Company who shall have signed the Shelf Registration
Statement and each director of the Company shall have the same rights to
contribution as the Company, subject in each case to the applicable terms and
conditions of this paragraph (d).

          (e) The provisions of this Section 6 shall remain in full force and
effect, regardless of any investigation made by or on behalf of any Holder or
the Company or any of the indemnified persons referred to in this Section 6, and
shall survive the sale by a Holder of Securities covered by the Shelf
Registration Statement.

          7. Rule 144A and Rule 144. The Company agrees with each Holder, for so
long as any Registrable Securities remain outstanding and during any period in
which the Company (i) is not subject to Section 13 or 15(d) of the Exchange Act,
to make available, upon request of any Holder, to such Holder of Registrable
Securities in connection with any sale thereof and any prospective purchaser of
such Registrable Securities designated by such Holder, the information required
by Rule 144A(d)(4) under the Act in order to permit resales of such Registrable
Securities pursuant to Rule 144A, and (ii) is subject to Section 13 or 15 (d) of
the Exchange Act, to make all filings required thereby in a timely manner in
order to permit resales of such Registrable Securities pursuant to Rule 144.

          8. Registration Defaults. (a) If, and only if, any of the following
events shall occur (each such event, a "Registration Default"), then the Company
shall pay liquidated damages (the "Registration Default Damages") to the Holders
of Registrable Notes in respect of the Notes as follows:

               (i) the Shelf Registration Statement is not filed, or on file,
          with the Commission prior to or on the Shelf Filing Deadline,
          commencing on the day following the Shelf Filing Deadline,
          Registration Default Damages shall accrue on the Registrable Notes at
          a rate of 0.25% per annum for the first 120 days from and including
          the day following the Shelf Filing Deadline and 0.50% per annum
          thereafter; or

               (ii) the Shelf Registration Statement has not become effective,
          or a previously effective Shelf Registration Statement has not been
          made available, prior to or on the Effectiveness Target Date,
          commencing on the date following the Effectiveness Target Date,
          Registration Default Damages shall accrue on the Registrable Notes at
          a rate of 0.25% per annum for the first 120 days from and including
          the day following the Effectiveness Target Date and 0.50% per annum
          thereafter; or

               (iii) the Shelf Registration Statement is filed and has become
          effective but, during the Shelf Registration Period, shall thereafter
          cease to be effective or


                                       15

<PAGE>

          fail to be usable for its intended purpose (other than pursuant to
          Section 3(c)(x) hereof) for more than 5 Business Days, Registration
          Default Damages shall accrue on the Registrable Securities at a rate
          of 0.25% per annum for the first 120 days from and including such date
          on which the Shelf Registration Statement ceases to be effective and
          0.50% per annum thereafter; or

               (iv) if the aggregate duration of Deferral Periods in any period
          exceeds the number of days permitted in respect of such period
          pursuant to Section 3(c)(x) hereof, then commencing on the day the
          aggregate duration of Deferral Periods in any period exceeds the
          number of days permitted in respect of such period, Registration
          Default Damages shall accrue on the Registrable Notes at a rate of
          0.25% per annum for the first 120 days from and including such date
          and 0.50% per annum thereafter.

     The Registration Default Damages payable as specified above shall be
determined:

                    (A) in respect of the Registrable Notes, to each holder of
               Notes as described in Section 8(i) through (iv); and

                    (B) in respect of the Registrable Notes submitted for
               conversion into Common Stock during the existence of a
               Registration Default with respect to the Common Stock, the holder
               will not be entitled to receive any Registration Default Damages
               with respect to such Common Stock but (x) will be entitled to a
               conversion rate adjustment, if any, in accordance with the terms
               of the Notes as set forth in the Indenture and (y) will receive
               from the Company on the settlement date with respect to such
               conversion, accrued and unpaid Registration Default Damages on
               the Registrable Notes calculated in accordance with paragraph (A)
               to the Conversion Date (as defined in the Indenture); and

          (b) Notwithstanding the foregoing, in no event will Registration
Default Damages be payable in connection with a failure to register the Common
Stock. For the avoidance of doubt, if the Company fails to register both the
Notes and the Common Stock, then the Registration Default Damages shall be
payable in connection with the failure to register the Notes.

          (c) The Company shall in no event be required to pay Registration
Default Damages in respect of more than one Registration Default at any one
time. Additionally, in no event will Registration Default Damages accrue at a
rate per year in excess of .50%.

          (d) Any amounts of Registration Default Damages due pursuant to
Section 8(a) will be payable in cash semi-annually in arrears on each April 1
and October 1, with the first semi-annual payment due on the first such payment
date after which a Registration Default occurs. A Holder will not be entitled to
Registration Default Damages as provided in Section 6 hereof, unless such Holder
has timely delivered to the Company a duly completed Notice and Questionnaire,
together with such other information reasonably requested of such Holder in
accordance with this Agreement.


                                       16

<PAGE>

          9. No Inconsistent Agreements. The Company has not entered into, and
agrees not to enter into, any agreement with respect to its securities that is
inconsistent with the rights granted to the Holders herein or that otherwise
conflicts with the provisions hereof.

          10. Amendments and Waivers. The provisions of this Agreement may not
be amended, qualified, modified or supplemented, and waivers or consents to
departures from the provisions hereof may not be given, unless the Company has
obtained the written consent of the Holders of a majority of the aggregate
principal amount of the Registrable Securities outstanding (provided that the
Holders of Shares issued upon conversion of Notes, which Shares are Registrable
Shares, shall not be deemed Holders of Shares, but shall be deemed Holders of
the aggregate principal amount at maturity of Notes from which such shares were
converted; provided, that, with respect to any matter that directly or
indirectly affects the rights of any Initial Purchaser hereunder, the Company
shall obtain the written consent of each such Initial Purchaser against which
such amendment, qualification, supplement, waiver or consent is to be effective;
provided, further, that no amendment, qualification, supplement, waiver or
consent with respect to Section 8 hereof shall be effective as against any
Holder of Registered Securities unless consented to in writing by such Holder;
and provided further, that the provisions of this Article 10 may not be amended,
qualified, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, unless the Company has obtained the
written consent of the Initial Purchasers and each Holder. Notwithstanding the
foregoing (except the foregoing provisos), a waiver or consent to departure from
the provisions hereof with respect to a matter that relates exclusively to the
rights of Holders whose Securities are being sold pursuant to a Shelf
Registration Statement and that does not directly or indirectly affect the
rights of other Holders may be given by the Majority Holders, determined on the
basis of Securities being sold rather than registered under such Shelf
Registration Statement.

          11. Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand-delivery, first-class mail,
telex, telecopier or air courier guaranteeing overnight delivery:

          (a) if to a Holder, at the most current address given by such holder
to the Company in accordance with the provisions of the Notice and
Questionnaire, which address initially is, with respect to each Holder, the
address of such Holder maintained by the Registrar under the Indenture;

          (b) if to the Initial Purchasers, initially at the address or
addresses set forth in the Purchase Agreement; and

          (c) if to the Company, initially at its address set forth in the
Purchase Agreement.

          All such notices and communications shall be deemed to have been duly
given when received.

          The Initial Purchasers or the Company by notice to the other parties
may designate additional or different addresses for subsequent notices or
communications.


                                       17

<PAGE>

          12. Remedies. Each Holder, in addition to being entitled to exercise
all rights provided to it herein, in the Indenture or in the Purchase Agreement
or granted by law, including recovery of liquidated or other damages, will be
entitled to specific performance of its rights under this Agreement. The Company
agrees that monetary damages would not be adequate compensation for any loss
incurred by reason of a breach by it of the provisions of this Agreement and
hereby agrees to waive in any action for specific performance the defense that a
remedy at law would be adequate.

          13. Successors. This Agreement shall inure to the benefit of and be
binding upon the parties hereto, their respective successors and assigns,
including, without the need for an express assignment or any consent by the
Company thereto, subsequent Holders of Securities, and the indemnified persons
referred to in Section 6 hereof. The Company hereby agrees to extend the
benefits of this Agreement to any Holder of Securities, and any such Holder may
specifically enforce the provisions of this Agreement as if an original party
hereto.

          14. Counterparts. This Agreement may be signed in one or more
counterparts, each of which shall constitute an original and all of which
together shall constitute one and the same agreement.

          15. Headings. The section headings used herein are for convenience
only and shall not affect the construction hereof.

          16. Applicable Law. This Agreement shall be governed by and construed
in accordance with the laws of the State of New York applicable to contracts
made and to be performed in the State of New York. The parties hereto each
hereby waive any right to trial by jury in any action, proceeding or
counterclaim arising out of or relating to this Agreement.

          17. Severability. In the event that any one of more of the provisions
contained herein, or the application thereof in any circumstances, is held
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of any such provision in every other respect and of
the remaining provisions hereof shall not be in any way impaired or affected
thereby, it being intended that all of the rights and privileges of the parties
shall be enforceable to the fullest extent permitted by law.

          18. Securities Held by the Company, etc. Whenever the consent or
approval of Holders of a specified percentage of principal amount of Securities
is required hereunder, Securities held by the Company or its Affiliates (other
than subsequent Holders of Securities if such subsequent Holders are deemed to
be Affiliates solely by reason of their holdings of such Securities) shall not
be counted in determining whether such consent or approval was given by the
Holders of such required percentage.


                                       18

<PAGE>

          If the foregoing is in accordance with your understanding of our
agreement, please sign and return to us the enclosed duplicate hereof, whereupon
this letter and your acceptance shall represent a binding agreement between the
Company and the several Initial Purchasers.

                                        Very truly yours,

                                        Allergan, Inc.


                                        By:  /s/ Jeffrey L. Edwards
                                            ------------------------------------
                                        Name: Jeffrey L. Edwards
                                              ----------------------------------
                                        Title:Executive Vice President,
                                              ---------------------------------
                                              Finance and Business Development,
                                              ---------------------------------
                                              Chief Financial Officer
                                              ---------------------------------

The foregoing Agreement is hereby confirmed and accepted as of the date first
above written.

Banc of America Securities LLC
Citigroup Global Markets Inc.
Morgan Stanley & Co. Incorporated

By: Bank of America Securities LLC

By: /s/ Derek Dillon
    ---------------------------------
Name: Derek Dillon
      -------------------------------
Title: Managing Director
       ------------------------------


By: Citigroup Global Markets Inc.


By: /s/ Graeme Gilfillan
    ---------------------------------
Name: Graeme Gilfillan
      -------------------------------
Title: Managing Director
       ------------------------------


                                       19