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                                                                     EXHIBIT 4.1

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                       MEDICIS PHARMACEUTICAL CORPORATION

                                      and

                      DEUTSCHE BANK TRUST COMPANY AMERICAS
                                       as
                                     Trustee

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                             Supplemental Indenture

                          Dated as of February 1, 2005

                                       to

                                    Indenture

                           Dated as of August 19, 2003

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      SUPPLEMENTAL INDENTURE ("SUPPLEMENTAL INDENTURE"), dated as of February 1,
2005, between MEDICIS PHARMACEUTICAL CORPORATION, a Delaware corporation (the
"COMPANY"), and DEUTSCHE BANK TRUST COMPANY AMERICAS, a New York banking
corporation duly organized and existing under the laws of the State of New York,
as Trustee (the "TRUSTEE").

      Capitalized terms used herein and not otherwise defined herein have the
meaning assigned to those terms in the Indenture.

WITNESSETH

      WHEREAS, the Company and the Trustee executed and delivered an Indenture,
dated as of August 19, 2003 (the "INDENTURE"), to provide for the issuance of
the Company's 1.5% Contingent Convertible Senior Notes Due 2033 (the "NOTES");

      WHEREAS, Section 9.01 of the Indenture permits the Company and the Trustee
to enter into one or more indentures supplemental to the Indenture without
notice to or consent of any Securityholder for the purpose of curing any defect
in the Indenture;

      WHEREAS, the Company seeks to enter into this Supplemental Indenture for
the purpose of correcting a defect in Section 10.06(d) of the Indenture and
requests that the Trustee execute this Supplemental Indenture pursuant to
Sections 9.01 and 9.06; and

      WHEREAS, all things necessary to make this Supplemental Indenture a valid
agreement according to its terms have been done.

      NOW, THEREFORE, the Companies agrees with the Trustee as follows:

ARTICLE 1
AMENDMENTS

      Section 1.01. Amendments to Indenture. Section 10.06(d) of the Indenture
shall be amended by deleting the word "dividing" on the sixteenth line of
Section 10.06(d) and replacing it with the word "multiplying".

                                        1
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ARTICLE 2
MISCELLANEOUS

      Section 2.01. Effect Of Supplemental Indenture. Upon the execution and
delivery of this Supplemental Indenture by each of the Company and the Trustee,
the Indenture shall be supplemented in accordance herewith, and this
Supplemental Indenture shall form a part of the Indenture for all purposes, and
every holder of Securities heretofore or hereafter authenticated and delivered
under the Indenture shall be bound thereby.

      Section 2.02. Confirmation Of Indenture. The Indenture, as supplemented
and amended by this Supplemental Indenture, is in all respects ratified and
confirmed, and the Indenture, this Supplemental Indenture and all indentures
supplemental thereto shall be read, taken and construed as one and the same
instrument.

      Section 2.03. Concerning The Trustee. The Trustee assumes no duties,
responsibilities or liabilities by reason of this Supplemental Indenture other
than as set forth in the Indenture.

      Section 2.04. Governing Law. This Supplemental Indenture shall be deemed
to be a contract made under the laws of the State of New York, and for all
purposes shall be construed in accordance with the laws of the State of New
York.

      Section 2.05. Separability. In case any provision contained in this
Supplemental Indenture shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.

      Section 2.06. Successors. All agreements of the Company in this
Supplemental Indenture shall bind its successor. All agreements of the Trustee
in this Supplemental Indenture shall bind its successor.

      Section 2.07. Counterparts. This Supplemental Indenture may be executed in
any number of counterparts, each of which shall be an original, but such
counterparts shall together constitute but one and the same instrument.

                                        2
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      IN WITNESS WHEREOF, the undersigned, being duly authorized, have executed
this Supplemental Indenture on behalf of the respective parties hereto as of the
date first written above.

                                          MEDICIS PHARMACEUTICAL
                                            CORPORATION

                                          By: /s/ Mark A. Prygocki, Sr.
                                              ----------------------------------
                                              Name:  Mark A. Prygocki, Sr.
                                              Title: Executive Vice President
                                                     Chief Financial Officer

                                          DEUTSCHE BANK TRUST COMPANY
                                            AMERICAS

                                          By: /s/ Susan Johnson
                                              ----------------------------------
                                              Name: Susan Johnson
                                              Title: Vice President

                                        3
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          Officers' Certificate relating to the Supplemental Indenture

      The undersigned hereby certify, pursuant to the Indenture (the
"INDENTURE") dated as of August 19, 2003 between Medicis Pharmaceutical
Corporation, a Delaware corporation (the "COMPANY"), and Deutsche Bank Trust
Company Americas, as trustee (the "TRUSTEE"), that:

      1. We are familiar with the Indenture and have read Sections 9.01 and
11.04 thereof.

      2. We have reviewed the Supplemental Indenture dated as of February 1,
2005 between the Company and the Trustee (the "SUPPLEMENTAL INDENTURE").

      3. We have made such examinations or investigations as are necessary to
enable us to express the opinion set forth in paragraph 4 below.

      4. We are of the opinion that the execution of the Supplemental Indenture
and the amendment contained therein have been authorized or permitted by the
Indenture and all conditions precedent to the execution of the Supplemental
Indenture have been complied with as of the date hereof.

      Capitalized terms used herein but not defined herein have the meanings set
forth in the Indenture.

      IN WITNESS WHEREOF, the undersigned have executed this Officers'
Certificate as of February 1, 2005.

                                       By: /s/ Jonah Shacknai
                                           -----------------------------
                                           Name: Jonah Shacknai
                                           Title: Chairman and
                                                  Chief Executive Officer

                                       By: /s/ Mark A. Prygocki, Sr.
                                           ------------------------------------
                                           Name: Mark A. Prygocki, Sr.
                                           Title: Executive Vice President,
                                                  Chief Financial Officer

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AKIN GUMP
STRAUSS HAUER & FELD LLP
_________ Attorneys at Law

                                                February 25, 2005

Deutsche Bank Trust Company Americas
Trust & Securities Services
60 Wall Street 27th Floor
New York, NY 10005
Attn: Susan Johnson

      Re:   Medicis Pharmaceutical Corporation 1.5% Contingent Convertible
            Senior Notes Due 2033

Ladies and Gentlemen:

      We have acted as counsel to Medicis Pharmaceutical Corporation, a Delaware
corporation (the "COMPANY"), in connection with the First Supplemental
Indenture, dated as of February 1, 2005 (the "SUPPLEMENTAL INDENTURE"), between
the Company and Deutsche Bank Trust Company Americas, as trustee (the
"TRUSTEE"), to the Indenture, dated as of August 19, 2003 (the "INDENTURE"),
between the Company and the Trustee, relating to the Company's 1.5% Contingent
Convertible Senior Notes due 2033 (the "NOTES"). This opinion letter is being
delivered to you pursuant to the requirements of Sections 9.01(b) and 11.04 of
the Indenture. All capitalized terms used in this opinion letter, without
definition, have the meanings assigned to them in the Indenture.

      In connection with this opinion letter, we have examined an executed
original of the Supplemental Indenture. In addition, we have examined the
following documents (collectively, the "DUE DILIGENCE DOCUMENTS"): (i) the
Certificate of the Company, dated February 1, 2005, delivered to the Trustee
pursuant to Sections 11.04 and 11.05 of the Indenture and (iii) the Indenture.

      We have examined originals or certified copies of such corporate records
of the Company and other certificates and documents of officials of the Company,
public officials and others as we have deemed appropriate for purposes of this
opinion letter. As to various questions of fact relevant to this opinion letter,
we have relied, without independent investigation, upon the Due Diligence
Documents, certificates of public officials, and other certificates of officers
of the Company, all of which we assume to be true, correct and complete. We wish
to inform you that our knowledge is necessarily limited due to the limited scope
of our review. In addition, we have

         590 Madison Avenue / New York, NY 10022-2524 / 212.872.1000 /
                      fax: 212.872.1002 / www.akingump.com
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AKIN GUMP
STRAUSS HAUER & FELD LLP
_______ Attorneys at Law

Deutsche Bank Trust Company Americas
February 25, 2005
Page 2

made no inquiry of the Company or any other person or entity (including
governmental authorities) regarding, and no review of, any judgments, orders,
decrees, franchises, licenses, certificates, permits or other public records or
agreements to which the Company is a party other than the officers' certificates
described above, and our knowledge of any such matters is accordingly limited.

      We have assumed the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, and the conformity to authentic original
documents of all copies submitted to us as conformed, certified or reproduced
copies. We have also assumed the legal capacity of natural persons, that the
Trustee has been duly authorized to execute, deliver and perform its obligations
under, and has duly executed and delivered, the Supplemental Indenture, and that
the Supplemental Indenture constitutes the legal, valid and binding obligation
of the Trustee, enforceable against the Trustee in accordance with its terms.

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

      1. The Supplemental Indenture is authorized by the Indenture and all
conditions precedent to the execution, delivery and performance of the
Supplemental Indenture have been satisfied.

      2. The execution and delivery of the Supplemental Indenture by the Company
do not, and the performance by the Company of its obligations under the
Supplemental Indenture will not, conflict with, or result in the breach of or
constitute a default under any of the terms, conditions or provisions of the
Indenture.

      3. The Supplemental Indenture constitutes the valid and binding obligation
of the Company, enforceable against the Company in accordance with its terms.

      4. The actions contemplated

      The opinions and other matters in this opinion letter are qualified in
their entirety and subject to the following:

A.  We express no opinion as to the (i) qualifications of the Trustee under the
    Trust Indenture Act or (ii) the ability of the Company or the Trustee to
    perform, observe or otherwise comply with the terms of the Supplemental
    Indenture.

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AKIN GUMP
STRAUSS HAUER & FELD LLP
________ Attorneys at Law

Deutsche Bank Trust Company Americas
February 25, 2005
Page 3

B.  We express no opinion as to the laws of any jurisdiction other than the
    Included Laws. We have made no special investigation or review of any
    published constitutions, treaties, laws, rules or regulations or judicial or
    administrative decisions ("LAWS"), other than a review of (i) the Laws of
    the State of New York, (ii) the General Corporation Law of the State of
    Delaware and (iii) the Federal Laws of the United States of America. For
    purposes of this opinion, the term "INCLUDED LAWS" means the items described
    in clauses (i), (ii) and (iii) of the preceding sentence that are, in our
    experience, normally applicable to transactions of the type contemplated by
    the Indenture. The term Included Laws specifically excludes (a) Laws of any
    counties, cities, towns, municipalities and special political subdivisions
    and any agencies thereof and (b) Laws relating to land use, zoning and
    building code issues, taxes, environmental issues, intellectual property
    Laws, antitrust issues, Federal Reserve Board margin regulation issues and
    securities law issues. Notwithstanding the foregoing, the term "Included
    Laws" specifically excludes laws, rules and regulations relating to the
    regulation of the conduct of the businesses of the Company and its
    Subsidiaries, including, without limitation, the pharmaceutical business.

C.  This opinion letter and the matters addressed herein are as of the date
    hereof or such earlier date as is specified herein, and we undertake no, and
    hereby disclaim any, obligation to advise you of any change in any matter
    set forth herein, whether based on a change in the law, a change in any fact
    relating to the Company or any other person, or any other circumstance. This
    opinion letter is limited to the matters expressly stated herein and no
    opinions are to be inferred or may be implied beyond the opinions expressly
    set forth herein.

D.  The matters expressed in this opinion letter are subject to and qualified
    and limited by (i) applicable bankruptcy, insolvency, fraudulent transfer
    and conveyance, reorganization, moratorium and similar laws affecting
    creditors' rights and remedies generally, (ii) general principles of equity,
    including principles of materiality, reasonableness, good faith and fair
    dealing (regardless of whether enforcement is sought in a proceeding at law
    or in equity), (iii) commercial reasonableness and unconscionability and an
    implied covenant of good faith and fair dealing, (iv) the possible
    unavailability of specific performance, injunctive relief or other equitable
    remedies and (v) securities Laws and public policy underlying such Laws with
    respect to rights to indemnification and contribution.

E.  This opinion letter is limited to the matters expressly stated herein and
    no opinions are to be inferred or may be implied beyond the opinions
    expressly set forth herein. We express no opinion with respect to the
    fairness of the Supplemental Indenture or any other matter, and in rendering
    the opinions expressed herein, we have assumed, with your consent, that a
    court of

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AKIN GUMP
STRAUSS HAUER & FELD LLP
_______ Attorneys at Law

Deutsche Bank Trust Company Americas
February 25, 2005
Page 4

    competent jurisdiction would find all such matters were entirely fair. We
    have assumed that no fraud, dishonesty, forgery, coercion, duress or breach
    of fiduciary duty exists or will exist with respect to any of the matters
    relevant to the opinions expressed in this opinion letter.

F.  We express no opinion as to whether a federal court located in the State of
    New York would have or would elect to exercise jurisdiction in a dispute
    arising under the Supplemental Indenture.

G.  The foregoing opinions are subject to the qualification that the
    enforceability of certain waivers, rights and remedies provided in the
    Supplemental Indenture may be unavailable or limited by certain laws and
    judicial decisions. In respect of such qualification, however, we are of
    the opinion that such laws and judicial decisions do not, subject to the
    other exceptions and limitations contained in this opinion letter, make the
    remedies generally afforded by the Supplemental Indenture inadequate for
    the practical realization of the benefits purported to be provided by such
    remedies with respect to the Trustee or the Holders' ability to realize
    upon the principal benefits or security intended to be provided by the
    Supplemental Indenture.

H.  We note that the provisions of the Supplemental Indenture that permit the
    Trustee or the Holders to take actions or make determinations, or to
    benefit from indemnities and similar undertakings by any other party
    thereto may be subject to a requirement that such action be taken or such
    determinations be made, and that any action or inaction by the Trustee or
    the Holders that may give rise to a request for payment under such an
    undertaking be taken, or not taken, on a reasonable basis and in good
    faith.

I.  This law firm is a registered limited liability partnership organized under
    the laws of the State of Texas.

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AKIN GUMP
STRAUSS HAUER & FELD LLP
_______ Attorneys at Law

Deutsche Bank Trust Company Americas
February 25, 2005
Page 5

J.  This opinion letter is solely for your benefit, and no other Persons shall
    be entitled to rely upon this opinion letter. Without our prior written
    consent, this opinion letter may not be quoted in whole or in part or
    otherwise referred to in any document and may not be furnished or otherwise
    disclosed to or used by any other Person, except for (i) delivery of copies
    hereof to counsel for the addressees hereof, (ii) inclusion of copies hereof
    in a closing file and (iii) use hereof in any legal proceeding arising out
    of the transactions contemplated by the Supplemental Indenture filed by an
    addressee hereof against this law firm or in which any addressee hereof is a
    defendant.

                                                Very truly yours,

                                                /s/ Akin Gump Strauss & Feld LLP

                                                Akin Gump Strauss & Feld LLP