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                                                                   EXHIBIT 10.57

                                                                    CONFIDENTIAL


                                 CONFIDENTIAL
               FIRST AMENDMENT TO INTERACTIVE SERVICES AGREEMENT
               -------------------------------------------------

        This First Amendment to Interactive Services Agreement (this "First
Amendment"), effective as of April 12, 2000 (the "First Amendment Date"), is
made and entered into by and between America Online, Inc. ("AOL"), a Delaware
corporation, with its principal offices at 22000 AOL Way, Dulles, Virginia
20166, and drkoop.com, Inc. ("Interactive Content Provider" or "ICP"), a
Delaware corporation, with its principal offices at 7000 N. Mopac Blvd., Suite
400, Austin, Texas 78731 (each a "Party" and collectively the "Parties").

                                   RECITALS
                                   --------

        WHEREAS, AOL and ICP entered into an Interactive Services Agreement,
effective as of July 1, 1999 (the "Agreement");

        WHEREAS, AOL and ICP each desires to amend the terms of the Agreement as
described in this First Amendment; and

        WHEREAS, defined terms used but not otherwise defined in this First
Amendment, including the Exhibits hereto, shall be as defined in the Agreement.

        NOW, THEREFORE, in consideration of the mutual covenants, promises and
agreements herein contained, the Parties hereto agree as follows:

                                     TERMS
                                     -----

1.      REFERENCES. All references in the Agreement to "this Agreement" or "the
        Agreement" (including indirect references such as "hereunder") are
        hereby deemed to be amended to refer to the Agreement as amended by this
        First Amendment.

2.      AMENDMENT TO SECTION 1.5. Section 1.5 of the Agreement is hereby deleted
        in its entirety. AOL shall have no impressions obligations to ICP
        whatsoever and any reference to an Impressions Target in the Agreement
        is hereby deleted.

3.      AMENDMENT TO SECTION 3.4 (CARRIAGE AND PROMOTIONAL FEE). Section 3.4 of
        the Agreement is hereby deleted in its entirety and replaced with the
        following Section 3.4:

        "3.4  CARRIAGE AND PROMOTIONAL FEE/OTHER.

              (a) Fee. ICP shall pay AOL $24,250,000 on the Effective Date
              ("Guaranteed Payment"). AOL acknowledges that ICP has paid in full
              the Guaranteed Payment.

              (b) Reduced Commitments.  Beginning on April 1, 2000:

                    (i)  AOL's sole carriage and programming obligations to ICP
                    pursuant to the Agreement shall be as set forth in Exhibit
                    H, AOL shall not be obligated to provide the Promotions set
                    forth in Section 1.1 or Exhibit A-1, and AOL shall have no
                    further obligations under Exhibit A. By way of clarification
                    and not limitation, AOL shall have all rights specified in
                    Section 1.1 and Exhibit A,

                    (ii) in addition to all other obligations set forth in the
                    Agreement, and in accordance with the terms of the
                    Agreement, as amended by this First Amendment, ICP shall
                    continue to provide the ICP Internet Site, the ICP
                    Programming and all existing Licensed Content for the
                    Netscape Netcenter, Digital City and AOL.com ("Selected
                    Properties") until at least the earlier of July 31, 2000 or
                    the date AOL notifies ICP that such Content should be

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Confidential treatment has been requested for portions of this exhibit. The
copy filed herewith omits the information subject to the confidentiality
request. Omissions are designated as ***. A complete version of this exhibit has
been filed separately with the Securities and Exchange Commission.

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                    removed from any Selected Property. If AOL does not request
                    that ICP remove such Content from a Selected Property by
                    July 31, 2000, ICP shall continue to provide such Content
                    unless and until AOL requests that ICP remove such Content;
                    provided that, ICP shall have the right after July 31, 2000,
                    upon thirty (30) days written notice to AOL, to discontinue
                    providing such programming for any Selected Property if AOL
                    does not provide promotions for such programming on such
                    Selected Property within any thirty (30) day period. By way
                    of clarification and not limitation, ICP shall continue to
                    provide the programming set forth in the Programming Plan
                    for the AOL Service and CompuServe unless AOL chooses to
                    remove, or directs ICP to remove, some or all of such
                    programming,

                    (iii) ICP shall not be entitled to Premier Status hereunder
                    and Section 1.6 of this Agreement (other than Section 1.6.2
                    (b)) shall be of no further force or effect, and

                    (iv) Section 8 of the Agreement shall be of no further force
                    or effect.

             (c) Other Agreements. ICP represents, warrants and covenants that
             ICP shall amend all of ICP's agreements with other Interactive
             Services to reduce all payments by ICP thereunder by at least ***
             on or before July 1, 2000. In the event ICP is unable to reduce its
             payments to other Interactive Services by *** on or before July 1,
             2000, AOL shall have an immediate right to terminate this Agreement
             without ICP having any right to cure. Notwithstanding anything to
             the contrary in this Agreement, (a) AOL shall be entitled, if it so
             elects, ***.

4.      AMENDMENT TO SECTION 3.9 (WARRANTS). Section 3.9 is hereby deleted in
        its entirety (including Exhibits H, I and J referenced therein) and
        replaced with the text set forth below, and the Time Warrant, Page View
        Warrant and PMRA previously issued thereunder to AOL are hereby
        cancelled by AOL and delivered herewith to ICP, each of which has been
        marked "CANCELLED" on the face thereof:

        "3.9  ISSUANCE OF COMMON STOCK. On April 12, 2000, ICP shall issue to
              AOL Three Million Five Hundred Thousand (3,500,000) shares of
              common stock of ICP, pursuant to a stock purchase agreement
              substantially in the form attached hereto as Exhibit I (the "Stock
              Purchase Agreement"), which shares shall be subject to the
              Registration Rights Agreement, dated as of July 1, 1999, by and
              between ICP and AOL. Such Stock shall be deemed fully earned by
              AOL upon receipt. ***. In addition, on or after April 12, 2000, to
              the extent the Company provides to any such Existing Interactive
              Services Provider any investors rights (including but not limited
              to registration rights, put rights or rights of first offer) on
              terms more favorable than the rights provided to AOL pursuant to
              this Agreement, the investors rights provided to AOL in connection
              with this Agreement shall be deemed to be amended to the extent
              necessary to provide investor rights to AOL on terms as favorable
              as the rights provided to such Existing Interactive Service
              Provider."

5.      AMENDMENT TO SECTION 4.2 (ADVERTISING SALES ON THE ICP INTERNET SITE AND
        THE DR. KOOP SITE).  Section 4.2 is hereby amended to add the following
        text at the end of such Section:

          "Notwithstanding the foregoing, beginning on April 1, 2000, ICP shall
          have the exclusive right to license or sell ICP Advertisements and to
          retain *** of all Advertising Revenues generated therefrom, but ICP
          shall not authorize or permit any third party to license or sell the
          ICP Advertisements, except that, nothing herein shall prohibit ICP
          from using any third

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          party to sell advertising on the Dr. Koop Site. ICP shall fully
          perform all of AOL's obligations pursuant to agreements for the
          license or sale of ICP Advertisements which were entered into by AOL
          pursuant to the Agreement prior to April 1, 2000. In addition, ICP
          fully releases and forever discharges AOL from and against any and all
          ICP charges, complaints, claims, demands, actions or causes of action,
          whether known or unknown, anticipated or unanticipated, of any kind,
          sort or nature whatsoever arising prior to the First Amendment Date,
          including without limitation those arising from, related to or
          concerning in any way AOL's license or sale of ICP Advertisements
          pursuant to the Agreement."

6.      AMENDMENT TO SECTION 7.1 (TERM). The first sentence of Section 7.1 of
        the Agreement is hereby deleted and replaced with the following text:

          "Unless earlier terminated as set forth herein, the initial term of
          this Agreement shall commence on the Effective Date and expire on
          April 15, 2001 (the "Initial Term")."

        In addition, the term "Section 5.4" on the fifth line of Section 7.1 of
        the Agreement shall be replaced with "Section 3.4".

7.      AMENDMENT TO SECTION 7.2 (TERMINATION FOR BREACH). The heading of
        Section 7.2 is hereby amended to read "Termination for Breach/Other."
        Section 7.2 is hereby deleted and replaced with the following text:

          "ICP may terminate this Agreement at any time in the event of a
          material breach by AOL which remains uncured after thirty (30) days
          written notice thereof. AOL may terminate this Agreement at any time
          in the event of a material breach by ICP upon written notice thereof,
          with no right to cure. This Agreement shall automatically terminate in
          the event that (a) a trustee, receiver, custodian, or similar official
          for ICP or any substantial portion of ICP's business is appointed, or
          (b) ICP stock fails to meet the listing requirements for any automated
          stock quotation system or national securities exchange on which such
          stock is listed. Notwithstanding any other provision herein, any right
          of AOL hereunder to terminate this Agreement which requires the
          provision of notice of such intent to terminate shall be exercisable
          by AOL without the requirement that AOL provide such notice if such
          notice is legally prohibited or stayed."

8.      AMENDMENT TO SECTION 7.4. Section 7.4 of the Agreement shall be deleted
        and replaced in its entirety with the following text:

        "7.4 ADDITIONAL TERMINATION RIGHTS. AOL shall have the right to
        terminate this Agreement in the event of one of the triggering events
        as set forth below:

             7.4.1 ICP has unpaid obligations to AOL or any third party which
             ICP is not disputing in good faith in excess of *** (in the
             aggregate); or

             7.4.2 The sum of ICP's "cash," "marketable securities" and
             available credit, credit lines and capital commitments falls below
             *** in any quarter as such are reported in ICP's Form 10-Q or in
             any report provided pursuant to Section 17 of the First Amendment.

             7.4.3 The occurrence of any event or combination of events which,
             in AOL's sole judgment, materially reduces the likelihood that ICP
             will be able fully and timely to comply with its obligations under
             the Agreement.

             7.4.4 Upon the occurrence of any of the foregoing, and
             notwithstanding anything to the contrary in the Agreement or any
             other agreement between the parties, AOL shall be permitted (but
             not required) to deliver to ICP a notice of termination of the
             Agreement, and the Agreement shall be terminated immediately upon
             ICP's receipt of such notice.

        AOL's right of termination under this Section 7.4 shall be immediate and
        ICP shall have no right to cure."

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9.   AMENDMENT TO SECTION 7.7 (TERMINATION ON CHANGE OF CONTROL).  Section 7.7
     is hereby amended only as follows: the term "Named Entity" shall be
     replaced with the term "Interactive Service."

10.  AMENDMENT TO ARTICLE IV OF EXHIBIT C (CONFIDENTIALITY).  Article IV of
     Exhibit C of the Agreement is amended to add the following text at the end
     of such Article:

          "ICP acknowledges and agrees that (x) any information about AOL's
          relationship with ICP, including without limitation, the substance or
          terms of the Agreement or the First Amendment, shall constitute
          Confidential Information under this Agreement, (y) that ICP's
          employees must comply with the provisions of this Article IV, and (z)
          that any disclosure by ICP's employees of any information set forth in
          clause (x) or any other Confidential Information, shall be deemed a
          material breach of this Agreement by ICP with no right to cure.
          Notwithstanding anything in the contrary in this Agreement or this
          Article IV, ICP shall use best efforts to ensure that ICP's employees
          to not disclose to any third party such Confidential Information."

11.  ADDITION OF NEW EXHIBIT H. Attachment 1 to this First Amendment is hereby
     added as a new Exhibit H to the Agreement.

12.  CONTINUANCE OF AGREEMENT. Except as modified by this First Amendment, the
     Agreement shall remain in full force and effect.

13.  STAY WAIVER

     In consideration for AOL's willingness to enter into this Amendment and its
     agreement to the restructuring contemplated thereby, ICP agrees that in the
     event that, after the Amendment Effective Date, ICP becomes subject to any
     bankruptcy or reorganization proceedings, and there is before or after the
     commencement of such bankruptcy proceedings any default under the Agreement
     or any event which under the terms of the Agreement would give AOL the
     right to terminate the Agreement (or event which, with the passage of time
     and/or the giving of notice would become a default or give rise to any
     right to terminate the Agreement) by ICP under the Agreement (or under any
     other agreement to which ICP and AOL are parties), ICP shall and hereby
     does stipulate and agree to the modification of the automatic stay of 11
     USC Section 362, and any other stay or injunction that may be in effect, so
     as to enable AOL to exercise each and every one of its rights and remedies
     under the Agreement, as amended hereby, including without limitation the
     right to terminate the Agreement, and ICP hereby waives any right to or
     benefit from any such stay or injunction. ICP agrees that it will not take
     any position or seek any relief in any bankruptcy case that is in any
     respect inconsistent with the foregoing agreements. ICP acknowledges that
     the foregoing agreement is appropriate because, among other things, (a) ICP
     is obtaining by virtue of the First Amendment the benefits of a
     restructuring of its relationship with AOL and substantial relief from
     financial obligations, and (c) it would be unfair and inequitable for ICP,
     having received the material benefit of the restructuring reflected by this
     Amendment, to then frustrate AOL's ability to exercise its rights and
     remedies under the Agreement by means of a bankruptcy filing. This Section
     13 is a material inducement to AOL to enter into this Amendment.

14.  ASSUMPTION/REJECTION

     ICP agrees that if it becomes subject to any proceedings under Title 11 of
     the United States Code, it will (a) *** and (b) will not seek to assume the
     Agreement without the express written consent of AOL. ICP acknowledges that
     the Related Agreements are part of a single contractual arrangement, such
     that it would be improper for ICP to seek to assume any of such Related
     Agreements without assuming all of them at the same time. For purposes of
     this section, the "Related Agreements" are the Agreement, as amended by
     this First Amendment, the Stock Purchase Agreement and the Development and
     Services Agreement by and between the Parties, effective as of July 1,
     1999.

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15.  CHAPTER 11 PLAN

     ICP agrees that if it becomes subject to any proceedings under Chapter 11
     of the Bankruptcy Code, or any similar or successor provision of state or
     federal law, it will not propose a plan of reorganization or liquidation
     that would alter in any way any of AOL's legal, contractual, or equitable
     rights against ICP, whether under the Agreement or otherwise, without the
     express consent of AOL.

16.  [INTENTIONALLY OMITTED].

17.  REPORTING REQUIREMENTS. ICP shall provide reports *** as requested by AOL.
     In addition, on the first business day of each month following the First
     Amendment Date, ICP shall complete and deliver to AOL a report, in a form
     designated by AOL, ***. Each such report shall be certified as complete and
     accurate by an officer of ICP.

18.  PERSONAL SERVICES. The parties agree and acknowledge that AOL is entering
     into the Agreement with ICP because of ICP's unique qualifications and
     reputation and because of ***.

19.  ADDITIONAL COVENANTS. ICP shall not incur any debt after the date of the
     First Amendment Date without the consent of AOL, other than (a) ordinary
     course of business trade credit, (b) debt incurred solely to purchase
     assets to be used in connection with ICP's current business and which is
     secured by such assets, (c) debt which is used to refinance existing debt
     in an amount no greater than the existing debt and on terms no less
     favorable to Koop than the existing debt, and (d) total unsecured debt not
     covered by (a), (b) or (c) hereof of not greater than $100,000 outstanding
     at any time.

20.  COUNTERPARTS. This First Amendment may be executed in counterparts, each of
     which shall be deemed an original and all of which together shall
     constitute one and the same document.



     IN WITNESS WHEREOF, the Parties hereto have executed this First Amendment
as of the First Amendment Date.

AMERICA ONLINE, INC.                        drkoop.com, Inc.


By: /s/ David M. Colburn                    By: /s/ Donald Hackett
    ------------------------------               ----------------------

Print Name: David M. Colburn                Print Name: Donald Hackett
            ----------------------                      ---------------

Title: President, Business Affairs          Title:  CEO
       ---------------------------                  -------------------

Date: April 14, 2000                        Date:  April 14, 2000
      ----------------------------                 --------------------

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                                 ATTACHMENT 1
                          EXHIBIT H TO THE AGREEMENT

                                CARRIAGE PLAN:
                                --------------

--------------------------------------------------------------------------------
              BRAND - SCREEN                           IMPRESSIONS
--------------------------------------------------------------------------------
         Level 1 Promotions
--------------------------------------------------------------------------------
CompuServe - Health and Fitness Main
--------------------------------------------------------------------------------
CompuServe - Contextual Placement Other
           - Content Articles
--------------------------------------------------------------------------------
 AOL Service - Today In Health
--------------------------------------------------------------------------------
 AOL Service - Contextual Placement Other
             - Text
--------------------------------------------------------------------------------
CompuServe - Contextual Placement Other
           - Text
--------------------------------------------------------------------------------
            Total Level 1:                                *** IMPRESSIONS
--------------------------------------------------------------------------------
         Level 3 Promotions
--------------------------------------------------------------------------------
CompuServe - News ROS
--------------------------------------------------------------------------------
            Total Level 3:                                *** Impressions
--------------------------------------------------------------------------------
         Level 4 Promotions
--------------------------------------------------------------------------------
CompuServe - Communications Channel
                ROS
--------------------------------------------------------------------------------
            Total Level 4:                                *** IMPRESSIONS
--------------------------------------------------------------------------------
         Level 5 Promotions
--------------------------------------------------------------------------------
         AOL Service - Email
--------------------------------------------------------------------------------
         CompuServe - Email
--------------------------------------------------------------------------------
            Total Level 5:                                *** IMPRESSIONS
--------------------------------------------------------------------------------
         Level 6 Promotion
--------------------------------------------------------------------------------
         CompuServe - Chat
--------------------------------------------------------------------------------
            Total Level 6:                                *** IMPRESSIONS
--------------------------------------------------------------------------------

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*** Certain information on this page has been omitted and filed separately with
the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.