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                                                                     Exhibit 3-B

                                                                          PAGE 1

                               State of Delaware

                        Office of the Secretary of State

                        --------------------------------

     I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF AMENDMENT
OF "ZILA, INC.", FILED IN THIS OFFICE ON THE FIFTEENTH DAY OF APRIL, A.D. 1998,
AT 2 O'CLOCK P.M.




                    [SEAL]              /s/ Edward J. Freel
                                            ------------------------------------
                                            Edward J. Freel, Secretary of State

2142913  8100                               AUTHENTICATION: 9027694

981143396                                             DATE: 04-15-98

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                            CERTIFICATE OF AMENDMENT
                                       TO
                          CERTIFICATE OF INCORPORATION

     ZILA, INC., a corporation organized and existing under and by virtue of
the General Corporation Law of the State of Delaware, DOES HEREBY CERTIFY:

     FIRST: That at a meeting of the Board of Directors of ZILA, INC. (the
"Corporation") on February 26, 1998, resolutions were duly adopted setting
forth a proposed amendment to the Certificate of Incorporation of the
Corporation, declaring said amendment to be advisable and directing that said
amendment be considered at the next special meeting of the stockholders of the
Corporation. The resolutions setting forth the proposed amendment are as
follows:

     RESOLVED, that Paragraph 1 of Article 4 of the Corporation's Certificate
of Incorporation be, and hereby is, amended in its entirety to read as follows:

     4. The total number of shares of capital stock which the Corporation shall
     have authority to issue is 67,500,000, divided into 65,000,000 shares of
     common stock of the par value $.001 per share and 2,500,000 shares of
     preferred stock of the par value of $.001 per share.

     SECOND: That thereafter, pursuant to resolution of its Board of Directors,
a special meeting of the stockholders of the Corporation was duly called and
held on April 14, 1998 upon notice in accordance with Section 222 of the
General Corporation Law of the State of Delaware, at which meeting the
necessary number of shares as required by statute were voted in favor of the
amendment.
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     THIRD: That said amendment was duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.

     IN WITNESS WHEREOF, Zila, Inc. has caused this certificate to be signed by
Joseph Hines, its President, this 14 day of April, 1998.


                                             Zila, Inc., a Delaware corporation
                                             ----------------------------------


                                             By  /s/ Joseph Hines
                                                 ------------------------------
                                                 Joseph Hines, President




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