EXHIBIT 10.17


                                AMENDMENT



     This is  an Amendment ("Amendment") dated August 3, 1998, to that
certain Agreement dated April 6, 1998 by and between Entropin, Inc.
("Entropin"),  a Colorado corporation and Western Center for Clinical
Studies, Inc. ("WCCS"), a California corporation.

     Article IV of the Agreement entitled "COMPENSATION TO WCCS" is hereby
amended to include the following provision:

     4.3  ACCELERATION OF COMPENSATION: In the event that WCCS performs all
          of the terms and conditions of this Agreement for which it is
          obligated prior to January 5, 2001 (the "Completion Date"):  (i)
          all payments pursuant to Section 4.1 shall be accelerated to the
          Completion Date; and, (ii) the Exercise Date of any stock options
          set forth in Section 4.2 which is subsequent to the Completion
          Date shall be accelerated to the Completion Date.

     Article VI of the Agreement entitled "DIRECTORS AND OFFICERS LIABILITY
INSURANCE" is hereby amended as follows:

     6.1  DIRECTORS AND OFFICERS LIABILITY INSURANCE:  During the Term,
          Entropin shall maintain directors and officers insurance in the
          aggregate amount of not less than Three Million Dollars
          ($3,000,000.00).  Such directors and officers insurance policy
          shall be a claims made policy.  If at any time the directors and
          officers insurance policy required hereby is not in effect, none
          of WCCS personnel, Daniel L.  Azarnoff, M.D., Roy S. Azarnoff,
          Ph.D., or Lois Rezler, Ph.D., shall have any obligation or duty
          to

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          perform any services for Entropin in their capacity as an officer
          or director as contemplated by paragraph 3.2 of this Agreement.
          Entropin agrees to maintain "tail" insurance covering Drs.
          Azarnoff and Rezler for not less than two (2) years after the
          termination of this Agreement.

     6.2  INDEMNIFICATION: WCCS agrees to indemnify, defend, and hold
          harmless Entropin, its employees, subcontractors or agents, for
          any and all claims, demands and expenses, including litigation
          costs, arising out of, or in any way resulting from or connected
          with the services or work provided by WCCS, its employees,
          subcontractors or agents.

          It is agreed that this indemnity agreement shall include any
          claim, demand or expense incurred arising out of, resulting from
          or in any way connected with the services provided by WCCS, its
          employees, subcontractors or agents for which WCCS, its
          employees, subcontractors, or agents is solely legally liable.

          It is agreed that WCCS shall carry a general liability policy and
          a products liability policy, each naming Entropin, its employees,
          subcontractors and agents as additional Insureds.  The policies
          shall be in force for a period of not less than two (2) years
          after the termination of the Agreement and shall have limits of
          not less than $2 million dollars.  It is the responsibility of
          WCCS to provide Entropin with the Certificate of Insurance and
          certified copies of the policies.  In the event that the
          aggregate limit of either policy is reduced below the agreed
          limit of $2 million dollars, it is the responsibility of WCCS to
          purchase additional limits to comply with the terms of this
          Agreement.

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IN WITNESS WHEREOF, the undersigned have entered into this AMENDMENT
effective August 3, 1998.

WESTERN CENTER FOR CLINICAL
   STUDIES, INC.                        ENTROPIN, INC.


By:        /s/ LOIS REZLER              By:  /s/ HIGGINS D. BAILEY
          --------------------------         --------------------------
          Lois Rezler                        Higgins D. Bailey
          President                          Chairman

Date: 8/3/98                            Date: 8-3-98









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