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                                                                     EXHIBIT 5.1


                        [LETTERHEAD OF KIRKLAND & ELLIS]


To Call Writer Directly:
    (212) 446-4800


                                   May 3, 2000


Warner Chilcott, Inc.
Rockaway 80 Corporate Center
100 Enterprise Drive, Suite 280
Rockaway, New Jersey  07866

         Re:      Exchange Offer for $200,000,000 12 5/8% Senior Notes due 2008
                  for $200,000,000 12 5/8% Series B Senior Notes due 2008

Dear Ladies and Gentlemen:

         We have acted as counsel to Warner Chilcott, Inc. (the "Company") and
the Parent Guarantor (together with the Company, the "Registrants") in
connection with the proposed offer (the "Exchange Offer") to exchange an
aggregate principle amount of up to $200,000,000 12 5/8% Senior Notes due 2008
(the "Old Notes") for $200,000,000 12 5/8% Series B Senior Notes due 2008 (the
"Exchange Notes"), pursuant to a Registration Statement on Form S-4 filed with
the Securities and Exchange Commission (the "Commission") under the Securities
Act of 1933, as amended (the "Securities Act"). Such Registration Statement, as
amended or supplemented, is hereinafter referred to as the "Registration
Statement". The Exchange Notes are to be issued pursuant to the Indenture (the
"Indenture"), dated as of February 15, 2000 by and among the Registrants and The
Bank of New York, as the Trustee, in exchange for and in replacement of the
Company's outstanding Old Notes, of which $200,000,000 in aggregate principal
amount is outstanding.

         In that connection, we have examined originals, or copies certified or
otherwise identified to our satisfaction, of such documents, corporate records
and other instruments as have deemed necessary for the purposes of this opinion,
including (i) the corporate and organizational documents of each of the
Registrants, (ii) minutes and records of the corporate proceedings of each of
the Registrants with respect to the issuance of the Exchange Notes, (iii) the
Registration Statement and exhibits thereto and (iv) the Notes Exchange and
Registration Rights Agreement, dated as of February 11, 2000, among the
Registrants, Credit Suisse First Boston, CIBC World Markets, and SG Cowen.

         For purposes of this opinion, we have assumed the authenticity of all
documents submitted to us as originals, the conformity to the originals of all
documents submitted to us as

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copies and the authenticity of the originals of all documents submitted to us as
copies. We have also assumed the genuineness of the signatures of persons
signing all documents in connection with which this opinion is rendered, the
authority of such persons signing on behalf of the parties thereto other than
the Registrants, and the due authorization, execution and delivery of all
documents by the parties thereto other than the Registrants. As to any facts
material to the opinions expressed herein which we have not independently
established or verified, we have relied upon statements and representations of
officers and other representatives of the Registrants and others.

         Based upon and subject to the foregoing qualifications, assumptions and
limitations and the further limitations set forth below, we are of the opinion
that:

         (i) Warner Chilcott, Inc. is in good standing under the laws of the
State of Delaware.

         (ii) The sale and issuance of the Exchange Notes has been validly
authorized by the Company.

         (iii) When the Exchange Notes are issued pursuant to the Exchange
Offer, the Exchange Notes will constitute valid and binding obligations of the
Registrants and the Indenture will be enforceable in accordance with its terms.

         Our opinions expressed above are subject to the qualifications that we
express no opinion as to the applicability of, compliance with, or effect of (i)
any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent
conveyance, moratorium or other similar law affecting the enforcement of
creditors' rights generally, (ii) general principals of equity (regardless of
whether enforcement is considered in a proceeding in equity or at law), and
(iii) except for purposes of the opinion in paragraph 1, any laws except the
laws except the laws of the State of New York.

         We hereby consent to the filing of this opinion in Exhibit 5.1 to the
Registration Statement. We also consent to the reference to our firm under the
heading "Legal Matters" in the Registration Statement. In giving this consent,
we do not thereby admit that we are in the category of persons whose consent is
required under Section 7 of the Securities Act of the rules and regulations of
the Commission.

         We do not find it necessary for the purposes of this opinion, and
accordingly we do not purport to cover herein, the application of the securities
or "Blue Sky" laws of the various states to the issuance of the Exchange Notes.

         This opinion is limited to the specific issues addressed herein, and no
opinion may be inferred or implied beyond that expressly stated herein. We
assume no obligation to revise or supplement this opinion should the present
laws of the State of New York be changed by legislative action, judicial
decision or otherwise.

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         This opinion is furnished to you in connection with the filing of the
Registration Statement, and is not to be used, circulated, quoted or otherwise
relied upon for any other purposes.


                                          Yours very truly,

                                          KIRKLAND & ELLIS