SECOND AMENDMENT TO
                             ASSET PURCHASE AGREEMENT

          THIS SECOND AMENDMENT to that certain Asset Purchase Agreement dated
September 1, 1998 (the "Purchase Agreement") by and between GalaGen Inc., a
Delaware corporation ("Buyer"), and Nutrition Medical, Inc., a Minnesota
corporation ("Seller"), is made as of this 23rd day of December, 1998.
Capitalized terms not otherwise defined herein are used with the meaning given
such terms in the Purchase Agreement.


                                      RECITALS

          The Purchase Agreement provides for Buyer to acquire certain assets of
Seller subject to the terms and conditions thereof.

          The Purchase Agreement was amended by an Amendment To Asset Purchase
Agreement (the "Amendment") dated as of September 28, 1998.

          The Amendment provides that Buyer will pay to Seller an International
Royalty on certain sales of the Products.  Buyer and Seller wish to further
specify in this Second Amendment the sales of the Products to which the
International Royalty applies.

                                     AGREEMENT

          NOW, THEREFORE, in consideration of the foregoing recitals and the
mutual covenants and conditions contained herein, the parties do hereby amend
the Purchase Agreement as follows:

1.   Section 2.2 is amended and restated in its entirety to read as follows:

     2.2  INTERNATIONAL ROYALTY.  Buyer will pay to Seller an international
     royalty (the "International Royalty") (a) of five percent (5%) of net
     International Sales (as defined herein), reduced by uncollectible accounts,
     in excess of $200,000 during the year ending on the first anniversary of
     the Closing Date, and (b) of two and one half percent (2 1/2%) of net
     International Sales, reduced by uncollectible accounts, in excess of
     $200,000 during the year ending on the second anniversary of the Closing
     Date.  Buyer will make payment, if any, of the International Royalty no
     later than 120 days after the end of the year to which such royalty
     relates, accompanied by such documentation as may be agreed upon by Buyer
     and Seller.  "International Sales" as used herein means sales made directly
     by Buyer of the Product known as "Glutasorb Ready to Use" to customers in
     all countries except the United States, Japan, France, England, Scotland,
     Belgium, Holland, Switzerland, Denmark, Sweden, Norway and Finland and
     sales made directly by Buyer of all Products other




     than "Glutasorb Ready to Use" to customers in all countries except the
     United States.

2.   Except as expressly set forth herein, the terms and conditions of the
     Purchase Agreement, as amended by the Amendment, remain unmodified and in
     full force and effect.

3.   This Second Amendment may be executed in counterparts, each of which shall
     be considered an original.

          IN WITNESS WHEREOF, the parties have caused this Second Amendment to
be executed by their duly authorized representatives to be effective as of the
date first given above.


NUTRITION MEDICAL, INC.                  GALAGEN INC.

By  /s/ Richard J. Hegstrand             By  /s/ Gregg A. Waldon
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  Its  COO                                Its  CFO
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