First Amendment to the
                   HEMATOCRIT DEVELOPMENT AND OPTION AGREEMENT

     An  Amendment  made as of the 27th  day of  February,  1998 by and  between
InMedica Development Corporation,  a Utah corporation doing business at 60 South
600 East, Suite 150, Salt Lake City, Utah 84102 (hereinafter  called "InMedica")
and Medical Physics,  Inc., a Utah  corporation  doing business at 825 North 300
West, Salt Lake City, Utah 84103 (hereinafter called "Medical Physics").

                                    RECITALS

     Whereas  InMedica  and Medical  Physics  have  previously  entered  into an
agreement  dated  August 29, 1997  relating  to the  conduct of certain  work on
InMedica's non-invasive hematocrit project (the "Agreement"); and

     Whereas the parties now desire to amend the Agreement in certain respects;

     Now  therefore,  for good  and  valuable  consideration,  the  receipt  and
sufficiency of which is hereby acknowledged, the parties agree as follows:

     1. Phase I Grant  Application.  Preparation and filing of the Phase I grant
application  referred  to in  paragraph 2 (1) of the  Agreement  shall be in the
discretion  and at the  expense  of Medical  Physics.  If the Phase I funding is
received,  providing the $100,000 of matching  funds  referred to in paragraph 2
(1) of the Agreement, shall be in the discretion of InMedica.

     2. Payment for Services  under the Agreement.  Medical  Physics agrees that
InMedica may compensate it in part for services  rendered under the Agreement by
payment in restricted common stock of InMedica,  valued at $.60 per share during
the  months of March,  April and May,  1998 by  immediately  issuing  to Medical
Physics  25,000 shares of its  restricted  common stock.  In addition,  InMedica
agrees to pay Medical  Physics  $10,000 cash per month during  March,  April and
May,  1998.  The  foregoing  compensation  arrangement  shall  be in lieu of the
$11,111 monthly payment obligation referred to in the Agreement. Medical Physics
agrees to execute a stock  issuance  agreement  relating to the  issuance of the
common  stock in the form  attached  hereto as Exhibit A, which is  incorporated
herein by reference.

     3.  Demonstration  of Prototype.  Medical  Physics agrees to be prepared to
demonstrate a prototype of the hematocrit measuring device on or before April 1,


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1998 and to conduct such  demonstations  of the device as InMedica  shall direct
during  the  months  of April  and May,  1998.  InMedica  acknowledges  that the
engineering of the prototype box need not be completed so long as the technology
is reasonably portable to locations where demonstrations may occur.

     4. Reaffirmation of Agreement.  Except as modified herein, the Agreement is
reaffirmed by the parties.

         IN WITNESS  WHEREOF the parties have executed this  agreement as of the
date first above written.

                                              INMEDICA DEVELOPMENT CORPORATION


                                              /s/ Larry E. Clark
                                              By Larry E. Clark, President


                                              MEDICAL PHYSICS, INC.


                                              /s/ Justin S. Clark
                                              Justin S. Clark, President





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