SECOND AMENDMENT TO CREDIT AGREEMENT THIS SECOND AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered into as of November 3, 1997, by and between ANDREW AND WILLIAMSON SALES, CO., a California corporation ("Borrower"), and WELLS FARGO BANK,...

                      SECOND AMENDMENT TO CREDIT AGREEMENT


         THIS SECOND AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered
into as of November 3, 1997, by and between XXXXXX AND XXXXXXXXXX  SALES, CO., a
California corporation ("Borrower"),  and XXXXX FARGO BANK, NATIONAL ASSOCIATION
("Bank").


                                    RECITALS
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         WHEREAS,  Borrower is currently  indebted to Bank pursuant to the terms
and conditions of that certain Credit Agreement  between Borrower and Bank dated
as of December 17, 1995, as amended from time to time ("Credit Agreement").

         WHEREAS,  Bank and Borrower have agreed to certain changes in the terms
and  conditions  set forth in the Credit  Agreement and have agreed to amend the
Credit Agreement to reflect said changes.

         NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which are  hereby  acknowledged,  the  parties  hereto  agree that the Credit
Agreement shall be amended as follows:

         1. Section 6.1(i) is hereby deleted in its entirety,  and the following
substituted therefor:

                  "(i) The failure of Guarantor  to maintain  Tangible Net Worth
         at all times greater than or equal to  $10,000,000.00,  with  "Tangible
         Net Worth" defined as the aggregate of total stockholders'  equity plus
         subordinated debt less any intangible assets."

         2. Except as specifically  provided herein, all terms and conditions of
the  Credit  Agreement  remain  in full  force  and  effect,  without  waiver or
modification.  All terms  defined  in the Credit  Agreement  shall have the same
meaning when used in this  Amendment.  This  Amendment and the Credit  Agreement
shall be read together, as one document.

         3. Borrower hereby remakes all representations and warranties contained
in the Credit Agreement and reaffirms all covenants set forth therein.  Borrower
further certifies that as of the date of this Amendment there exists no Event of
Default  as defined in the Credit  Agreement,  nor any  condition,  act or event
which with the giving of notice or the passage of time or both would  constitute
any such Event of Default.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the day and year first written above.

XXXXXX AND XXXXXXXXXX SALES, CO.



By     /s/ XXXX X. XXXXXXXXXX
           XXXX X. XXXXXXXXXX
                  President


XXXXX FARGO BANK,
  NATIONAL ASSOCIATION




By:     /s/ XXXX X. XXXXXXX
        XXXX X. XXXXXXX
           Vice President



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         Acknowledged  by  the  undersigned  ("Guarantor"),  which  specifically
acknowledges  that the  failure of  Guarantor  to  maintain  Tangible  Net Worth
(defined as the aggregate of total  stockholders'  equity plus subordinated debt
less any intangible assets) at all times greater than or equal to $10,000,000.00
shall constitute an "Event of Default" under the foregoing Credit Agreement.


EPITOPE, INC.



By:      /s/ XXXXXXX X. XXXXXX
         XXXXXXX X. XXXXXX
         Executive Vice President/
         Chief Financial Officer



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