Exhibit 5




                  [Letterhead of Fulbright & Jaworski L.L.P.]




September 28, 1998


Bio-Technology General Corp.
70 Wood Avenue South
Iselin, New Jersey  08830

Dear Sirs:

            We refer to the Registration Statement on Form S-8 (the
"Registration Statement") to be filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended (the "Act"), on behalf
of Bio-Technology General Corp., a Delaware corporation (the "Company"),
relating to 3,000,000 shares of the Company's Common Stock, $.01 par value (the
"Common Stock"), to be issued pursuant to the Bio-Technology General Corp. 1998
Employee Stock Purchase Plan (the "Plan").

            As counsel to the Company, we have examined such corporate records,
other documents and such questions of law as we have deemed necessary or
appropriate for the purposes of this opinion and, upon the basis of such
examinations, advise you that in our opinion all necessary corporate proceedings
by the Company have been duly taken to authorize the issuance of the Common
Stock pursuant to the Plan and the shares of Common Stock being registered
pursuant to the Registration Statement, when issued and paid for in accordance
with the terms of the Plan, will be duly authorized, validly issued, fully paid
and non-assessable.

            We consent to the filing of this opinion as Exhibit 5 to the
Registration Statement. This consent is not to be construed as an admission that
we are a person whose consent is required to be filed with the Registration
Statement under the provisions of the Act.

                             Very truly yours,


                             /s/ Fulbright & Jaworski L.L.P.