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                                                                     EXHIBIT 5.1



                        [COOLEY GODWARD LLP LETTERHEAD]



February 3, 1998


Allergan Specialty Therapeutics, Inc.
2525 Dupont Drive
Irvine, CA  92612

Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection
with the filing by Allergan Specialty Therapeutics, Inc., a Delaware corporation
(the "Company"), of a Registration Statement on Form S-1 (File No. 333-40503)
(the "Registration Statement") with the Securities and Exchange Commission,
including a related prospectus filed with the Registration Statement (the
"Prospectus"), and the distribution, pursuant to the terms of a Distribution
Agreement (the "Distribution Agreement") to be entered into between Allergan,
Inc. ("Allergan") and the Company, of an aggregate of 3,300,000 shares of the
Company's Class A Common Stock, $.01 par value (the "Shares"), by Allergan to
its stockholders.

In connection with this opinion, we have assumed the genuineness and
authenticity of all documents submitted to us as originals, the conformity to
originals of all documents submitted to us as copies thereof and the due
execution and delivery of all documents where due execution and delivery are a
prerequisite to the effectiveness thereof. We have based our opinion upon our
examination of the following records, documents and instruments:

     (a) The Certificate of Incorporation of the Company certified by the
Secretary of State of the State of Delaware as of November 12, 1997, and
certified to us by an officer of the Company as being complete and in full force
and effect as of the date of this opinion;

     (b) The form of Restated Certificate of Incorporation of the Company filed
as an exhibit to the Registration Statement (the "Restated Certificate");

     (c) The Bylaws of the Company certified to us by an officer of the Company
as being complete and in full force and effect as of the date of this opinion;



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February 3, 1998
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     (d) The form of Distribution Agreement filed as an exhibit to the
Registration Statement;

     (e) A Certificate of the Associate General Counsel and Assistant Secretary
of the Company: (i) attaching records certified to us as constituting all
records of proceedings and actions of the Board of Directors of the Company
relating to the issuance and distribution of the Shares; and (ii) certifying as
to certain factual matters;

     (f) The Registration Statement and related Prospectus; and

     (g) Such other documents, records, certificates, memoranda and other
instruments as we deemed necessary as a basis for this opinion.

This opinion is limited to the general corporation laws of the State of
Delaware. We disclaim any opinion as to any other statute, rule, regulation,
ordinance, order or other promulgation of any other jurisdiction or any regional
or local governmental body.

Based upon the foregoing and our examination of such questions of law as we have
deemed necessary or appropriate for the purpose of this opinion, and assuming
that: (i) the Restated Certificate is filed with and accepted by the Delaware
Secretary of State, (ii) the Company and Allergan enter into and perform their
respective obligations under the Distribution Agreement, (iii) the consideration
for such Shares recited in the Distribution Agreement has been received, and
(iv) appropriate stock certificates evidencing the Shares will be properly
executed and delivered, it is our opinion that the Shares covered by the
Registration Statement when issued by ASTI will be validly issued, fully paid
and nonassessable.

This opinion is rendered to you in connection with the Registration Statement
and is solely for the benefit of the Company and its stockholders. This opinion
may not be relied upon for any other purpose, or relied upon by any other
person, firm, corporation or other entity for any purpose, without our prior
written consent. We disclaim any obligation to advise you of any developments
that occur after the date of this opinion.



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Allergan Specialty Therapeutics, Inc.
February 3, 1998
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We consent to the reference to our firm under the caption "Legal Matters" in the
Prospectus included in the Registration Statement and to the filing of this
opinion as an exhibit to the Registration Statement.


Respectfully,

COOLEY GODWARD LLP


Thomas A. Coll