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                                                                     Exhibit 5.1

                 Opinion of Akerman, Senterfitt & Eidson, P.A.

                                                   July 31, 2001



IVAX Corporation
4400 Biscayne Boulevard
Miami, Florida 33137

Ladies and Gentlemen:

         We have acted as counsel to IVAX Corporation, a Florida corporation
(the "Company"), in connection with the preparation and filing with the
Securities and Exchange Commission (the "Commission") of a Registration
Statement on Form S-3 (the "Registration Statement"), under the Securities Act
of 1933, as amended (the "Securities Act"), relating to the registration by the
Company of (i) $725,000,000 of principal amount of its 4 1/2% Convertible Senior
Subordinated Notes due 2008 (the "4 1/2% Notes") and (ii) 18,102,344 shares of
the Company's common stock, par value $.10 per share, issuable upon conversion
of the 4 1/2% Notes (the "Conversion Shares"), all of which are to be sold by
certain holders of the 4 1/2% Notes or the Conversion Shares as described in the
Registration Statement. The Notes were issued under an Indenture, dated as of
May 4, 2001, between the Company and U.S. Bank Trust National Association, as
trustee (the "Indenture").

         In so acting, we have examined originals, or copies certified or
otherwise identified to our satisfaction, of (i) the Registration Statement and
the exhibits thereto, (ii) the Indenture; (iii) the Registration Rights
Agreement, dated May 4, 2001, between the Company and UBS Warburg LLC, as
initial purchaser; (iv) the form of the 4 1/2% Notes; (v) the Articles of
Incorporation of the Company, as amended; and (vi) such documents, records,
certificates and other instruments of the Company as in our judgment are
necessary or appropriate for purposes of this opinion. In our examination of the
aforesaid documents, we have assumed, without independent investigation, the
genuineness of all signatures, the legal capacity of all individuals who have
executed any of the documents, the authenticity of all documents submitted to us
as originals and the conformity to the original documents of all copies.

         Based upon the foregoing examination, we are of the opinion that (i)
the 4 1/2% Notes are legally issued and binding obligations of the Company,
subject to applicable bankruptcy, insolvency, reorganization, receivership,
arrangement, fraudulent conveyance, moratorium or other similar laws affecting
creditor' rights generally and general principals of equity regardless of
whether such enforceability is considered in a proceeding in equity or at law
and (ii) the Conversion Shares have been duly authorized by the Company,



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IVAX Corporation
July 31, 2001
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and when issued and delivered in accordance with the terms of the Indenture,
will be validly issued, fully paid and nonassessable, assuming no change in
applicable law.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the caption "Legal
Matters" in the Registration Statement. In giving such consent, we do not
thereby admit that we are included within the category of persons whose consent
is required under Section 7 of the Securities Act or the rules and regulations
of the Commission thereunder.

                                       Sincerely,


                                       AKERMAN, SENTERFITT & EIDSON, P.A.

                                       /s/ Akerman, Senterfitt & Eidson, P.A.