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                                                                   EXHIBIT 10.98

                   AMENDMENT NO. 1 TO ASSET PURCHASE AGREEMENT


                This AMENDMENT NO. 1 TO ASSET PURCHASE AGREEMENT (this
"Amendment") is dated as of July __, 2001 and entered into by and among IVonyx
Group Services, Inc., a Delaware corporation ("IVonyx"), IVonyx, Inc., a
California corporation and a wholly-owned subsidiary of IVonyx ("IVonyx Sub"),
drkoop LifeCare, Inc. (formerly known as Infusion Acquisition Sub, Inc.), a
Delaware corporation ("Acquisition Sub"), and drkoop.com, Inc., a Delaware
corporation ("Parent" and, together with Acquisition Sub, the "Koop Parties").
IVonyx and IVonyx Sub are collectively referred to herein as the "IVonyx
Parties" or individually as an "IVonyx Party."

                                 R E C I T A L S


                WHEREAS, on April 13, 2001, IVonyx, IVonyx Sub, Acquisition Sub
and Parent entered into the Asset Purchase Agreement (the "Purchase Agreement");
and

                WHEREAS, pursuant to Section 12.6 of the Purchase Agreement,
IVonyx, IVonyx Sub, Acquisition Sub and Parent now desire to amend the Purchase
Agreement as hereinafter provided.

                                A M E N D M E N T


                NOW, THEREFORE, the Parties agree as follows:

        1. All capitalized terms used herein and not otherwise defined herein
shall have the respective meanings assigned thereto in the Purchase Agreement.

        2. Section 1.1 is hereby amended by (A) deleting the definitions for the
terms "Average Price", "Proxy Statement" and "Registration Statement" in their
entirety, (B) adding the following definitions in alphabetical order:

        ""Bonus Amount" shall Five Million Dollars ($5,000,000).

        "Reduced Target Amount" shall mean Two Million Dollars ($2,000,000)."

        3. Section 1.2 is hereby amended by (A) inserting the words "Additional
Shares" (immediately below the listing of the term "Acquisition Sub Financial
Statements") as a term defined in Section 2.3, (B) inserting the words "Bonus
Earnout Payment" (immediately below the listing of the term "Audited Financial
Statements") as a term defined in Section 2.5(a), (C) inserting the words
"Contingent Shares Right" (immediately below the listing of the term "Contested
Claim") as a term defined in Section 2.3, (D) inserting the words "Investment
Representation Letter and Lock-Up Agreement" (immediately below the listing of
the term "Independent Accountant") as a term defined in Section 2.3 , (E)
inserting the words "Preferred



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Stockholders" (immediately below the listing of the term Permitted Transferee)
as a term defined in Section 4.26(e); (F) inserting the words "Reduced Target
Earnout Payment" (immediately below the listing of the term "Purchase Price
Allocation Schedule") as a term defined in Section 2.5(a), (G) inserting the
words "Target Earnout Payment" (immediately below the listing of the term
"Shares") as a term defined in Section 2.5(a), (H) inserting the word "Transfer"
(immediately below the listing of the term "Termination Date") as a term defined
in Section 11.10, and (I) inserting the words "Unpaid Cash Payment" (immediately
below the listing of the term "Uncontested Claim") as a term defined in Section
2.5(a).

        4. Section 2.3 is hereby deleted and replaced with the following Section
2.3:

                "2.3 Consideration. On the Closing Date (as defined below), upon
        the terms and subject to the conditions set forth herein, in
        consideration for the transfer of the Assets of the IVonyx Parties
        pursuant to Section 2.1 of this Agreement, Parent shall pay an aggregate
        purchase price (the "Purchase Price") comprised of: (a) Two Million
        Dollars ($2,000,000.00) in cash which shall be payable at the Closing by
        certified or bank cashier's check or by wire transfer of immediately
        available funds to a trust account established by IVonyx's counsel or
        such other account designated by IVonyx, (b) the issuance by Parent to
        IVonyx of five million (5,000,000) shares of Common Stock (the "Initial
        Shares"), of which stock certificates evidencing ninety percent (90%) of
        the Shares (the "Non-Escrowed Shares") shall be delivered to IVonyx at
        the Closing and the remainder shall be placed in escrow in accordance
        with Section 2.4 below, and (c) the contingent right (the "Contingent
        Shares Right") to receive additional shares of Common Stock (the
        "Additional Shares" and collectively with the Initial Shares, the
        "Shares") pursuant to Section 2.5 below. It is the intention of IVonyx
        to immediately distribute the Initial Shares and allocate the Contingent
        Shares Right to its Preferred Stockholders (as defined in Section
        4.26(e)) and, promptly following the Closing, IVonyx shall distribute
        the Initial Shares and allocate the Contingent Shares Right to its
        Preferred Stockholders (it being understood that the Contingent Shares
        Right shall be allocated among the Preferred Stockholders
        proportionately to the relative number of Initial Shares distributed to
        each Preferred Stockholder); provided that such distribution shall be
        subject to each Preferred Stockholder that is to receive any Initial
        Shares in connection with such distribution (and any transferee thereof)
        completing, executing and delivering to Parent an Investment
        Representation Letter and Lock-Up Agreement in the form of Exhibit E
        attached hereto (the "Investment Representation Letter and Lock-Up
        Agreement") or otherwise agreeing in writing, in a manner reasonably
        acceptable to Parent, to be bound by the transfer restrictions contained
        in Article XI hereof. At the written request of IVonyx, the Non-Escrowed
        Shares shall be issued directly to the Preferred Stockholders to which
        IVonyx distributes such Non-Escrowed Shares pursuant to the preceding
        sentence; provided, however that each such Preferred Stockholder
        completes, executes and delivers to Parent an Investment Representation
        Letter and Lock-Up Agreement or otherwise agrees in writing, in a manner
        reasonably acceptable to Parent, to be bound by the transfer
        restrictions contained in Article XI hereof."

        5. Section 2.4 is hereby amended by (A) deleting each reference to the
word "Shares" in the first sentence thereof and replacing them with the words
"Initial Shares" and



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(B) deleting the word "stockholders" in the last sentence thereof and replacing
it with the words "Preferred Stockholders".

        6. Section 2.5(a) is hereby deleted and replaced with the following
Section 2.5(a):

                "2.5 Earnout.

                        (a) In connection with this Section 2.5, Acquisition Sub
        shall deliver to the Representative no later than sixty (60) days
        following the end of the twelfth (12th) full calendar month following
        the Closing Date (such twelve (12) full month period beginning with the
        first day of the first month following the Closing Date and ending on
        the end of the twelfth (12th) full calendar month of such date, the
        "Earnout Period"), financial statements of Acquisition Sub setting forth
        the amount of aggregate Net Income of Acquisition Sub (the "Acquisition
        Sub Financial Statements"), along with a reasonably detailed description
        of the calculations of the amount of the aggregate Net Income. In the
        event Net Income of Acquisition Sub: (i) equals or exceeds the Bonus
        Amount, Acquisition Sub shall (A) pay to IVonyx $2,000,000, of which
        $1,000,000 shall be paid in four equal quarterly installments with the
        first installment due on the first day of the month following the end of
        the third Earnout Period, and (B) issue to IVonyx 7,500,000 shares of
        Common Stock (the "Bonus Earnout Payment"); (ii) equals or exceeds the
        Target Amount and is less than the Bonus Amount, Acquisition Sub shall
        (A) pay to IVonyx $2,000,000, of which $1,000,000 shall be paid in four
        equal quarterly installments with the first installment due on the first
        day of the month following the three month period after the end of the
        Earnout Period, and (B) issue to IVonyx 2,500,000 shares of Common Stock
        (the "Target Earnout Payment"); or (iii) does not equal or exceed the
        Target Amount but equals or exceeds the Reduced Target Amount,
        Acquisition Sub shall (A) pay to IVonyx $666,667 plus an incremental 33%
        of the amount by which Net Income exceeds the Reduced Target Amount, to
        be paid in four equal quarterly installments with the first installment
        due on the first day of the month following the three month period after
        the end of the Earnout Period (the "Reduced Target Earnout Payment,"
        with each of the Bonus Earnout Payment and the Target Earnout Payment
        referred to herein as an "Earnout Payment"), in each case in accordance
        with the terms of this Section 2.5. Unless the Representative gives
        written notice to Acquisition Sub on or before the twentieth (20th)
        calendar day after the Representative's receipt of the Acquisition Sub
        Financial Statements, specifying in reasonable detail all disputed items
        and the basis therefor, the Representative shall be deemed to have
        accepted the Acquisition Sub Financial Statements and Acquisition Sub
        shall have (i) no obligation to pay any Earnout Payment to IVonyx if Net
        Income is less than the Reduced Target Amount or (ii) an obligation to
        pay the applicable Earnout Payment if Net Income is above the Reduced
        Target Amount. If the Representative so notifies Acquisition Sub of his
        objection to the Acquisition Sub Financial Statements, the
        Representative and Acquisition Sub shall, within twenty (20) days
        following such notice, attempt to resolve their differences in good
        faith, and any resolution by them as to any disputed amounts shall be
        final, binding and conclusive. If, at the end of such twenty (20) day
        period, the Representative and Acquisition Sub are unable to resolve
        such disagreements, the independent accountants of Acquisition Sub and
        the Representative shall jointly select a third independent auditor of
        recognized national standing to resolve any remaining



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        disagreements, which third independent auditor shall not have provided
        accounting services to Acquisition Sub, Parent or any IVonyx Party
        during the five (5) year period immediately preceding the Closing Date,
        and which auditor so selected will be set forth in writing and will be
        conclusive and binding upon the Parties (the "Independent Accountant").
        Acquisition Sub and the Representative shall use their reasonable
        efforts to cause the Independent Accountant to make its determination
        within thirty (30) calendar days of accepting its selection. The
        determination by the Independent Accountant shall be final, binding and
        conclusive on the Parties. The fees and expenses of the Independent
        Accountant shall be borne by the Representative if the Net Income
        determined by the Independent Accountant is less than the amount that
        would qualify IVonyx to receive the next highest Earnout Payment (e.g.,
        if the Acquisition Sub Financial Statements delivered by Acquisition Sub
        indicate that Net Income is less than the Target Amount, the fees and
        expenses of the Independent Accountant would be borne by IVonyx unless
        the Independent Accountant determined that actual Net Income exceeded
        the Target Amount); otherwise, the fees and expenses of the Independent
        Accountant shall be borne by Acquisition Sub. Subject to Section 10.13
        below, within ten (10) calendar days after (i) receipt by the
        Representative of Acquisition Sub Financial Statements which reflect
        aggregate Net Income equal to or in excess of the Reduced Target Amount,
        or (ii) in the event of a disagreement, the date of determination by the
        Independent Accountant that aggregate Net Income equals or exceeds the
        Reduced Target Amount, Acquisition Sub shall pay the Bonus Earnout
        Payment, the Target Earnout Payment or the Reduced Earnout Payment, as
        applicable, to IVonyx; provided, however, that if the Independent
        Accountant determines that IVonyx is entitled, under this Section 2.5,
        to an Earnout Payment from Acquisition Sub different from the Earnout
        Payment that Acquisition Sub would be obligated to pay based on the
        Acquisition Sub Financial Statements delivered by Acquisition Sub,
        Acquisition Sub shall pay the cash component of the applicable Earnout
        Payment that was not yet paid (any such cash portion, the "Unpaid Cash
        Payment"), if any, with interest from the period commencing on the date
        such Unpaid Cash Payment would have been required to be paid had the
        Acquisition Sub Financial Statements reflected the determination of the
        Independent Accountant when initially delivered by Acquisition Sub to
        the date the Unpaid Cash Payment is actually paid, at the compound rate
        of ten percent (10%) per annum."

        7. Section 2.5(b) is hereby deleted and replaced with the following
Section 2.5(b):

                        "(b) The cash component, if any, of any Earnout Payment
        (and any interest thereon) shall be made by cashiers or certified bank
        check or by wire transfer of immediately available funds to an account
        specified by IVonyx. Any Earnout Payment shall, to the extent required
        by law, be deemed to include interest at the applicable federal rate
        under the Code (it being understood that such deemed interest will not
        affect the amount due and payable under this Section 2.5). At the
        written request of IVonyx, the Additional Shares, if any, shall be
        issued directly to the stockholders to which IVonyx distributed
        Non-Escrowed Shares pursuant to Section 2.3 in proportion to the
        relative portion of the Contingent Shares Right allocated to each
        Preferred Stockholder."

        8. Section 2.5(e) is hereby amended by deleting the last paragraph
thereof and replacing it with the following:



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                "In the event that one or more Events of Default described in
        subsection (i) above shall occur, then the applicable Earnout Payment
        shall be immediately due and payable if Acquisition Sub fails to cure
        such Event of Default within five (5) business days of receipt of
        written notice thereof. In the event that one or more Events of Default
        described in subsections (ii) or (iii) above shall occur, then the
        Target Earnout Payment shall be immediately due and payable without
        demand, notice or declaration of any kind whatsoever, notwithstanding
        whether or not the Net Income equals or would have equaled the Target
        Amount. In the event of the occurrence of any Event of Default, IVonyx
        may exercise any remedies set forth in this Section 2.5 or otherwise in
        this Agreement or any other rights and remedies available to IVonyx
        under applicable law."

        9. Section 3.1 is hereby amended to add to the end the following: "The
parties shall exert best efforts to satisfy all conditions as soon as possible
on or after August 1, 2001, time being of the essence in the Closing of the
transactions that are the subject of the Agreement, as amended hereby."

        10. Section 3.2 is hereby amended by (A) deleting the words "Zevnik
Horton Palmer LLP" from clause (k) and replacing them with the words "Foley &
Lardner" and (B) adding the following clause (q):

                        "(q) Investment Representation Letters and Lock-Up
        Agreements previously completed and executed by each Preferred
        Stockholder of IVonyx that will receive Initial Shares from IVonyx
        following consummation of the transactions contemplated hereby."

        11. Section 4.24 is hereby amended by (A) deleting each reference to the
words "Registration Statement" therein and replacing them with the words
"Information Statement" and (B) deleting the words "filed with the SEC and at
the time it becomes effective under the Securities Act" therein and replacing
them with the words "delivered to the stockholders of IVonyx".

        12. Article IV is hereby amended by adding the following Section 4.26:

                "4.26 Investor Representations.

                        (a) IVonyx understands that (i) the Shares have not been
        registered under the Securities Act, nor qualified under the securities
        laws of any other jurisdiction, (ii) the Shares cannot be resold unless
        they subsequently are registered under the Securities Act and qualified
        under applicable state securities laws or foreign securities laws,
        unless exemptions from such registration and qualification requirements
        are available, and (iii) IVonyx has no right to require such
        registration or qualification (except pursuant to Article XI hereof).

                        (b) IVonyx is an "accredited investor" (as such term is
        defined in Section 501 of Regulation D of the Securities Act) and has
        substantial knowledge and experience in financial and business matters,
        has specific experience making investment decisions of a similar nature,
        and is capable, without the use of a financial advisor, of utilizing and
        analyzing the information made available in connection with the
        acquisition of the Shares



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        under this Agreement and of evaluating the merits and risks of an
        investment in the Shares.

                        (c) IVonyx is able to bear the economic risk of its
        investment in the Shares for an indefinite period of time because (i)
        there is no assurance that the business of Acquisition Sub will be
        economically successful and (ii) the Shares have not been registered
        under the Securities Act and, therefore, cannot be sold unless
        subsequently registered under the Securities Act or a valid exemption
        from such registration is available and are subject to restrictions on
        transfer as provided in the Article XI hereof.

                        (d) IVonyx has had an opportunity to ask questions and
        receive answers concerning the terms and conditions of the offering of
        the Shares, has had full access to such other information concerning
        Parent as it has requested and has not received and is not relying upon
        any written offering literature or prospectus. Without limiting the
        generality of the foregoing, IVonyx is not relying upon any oral
        representations which are in any manner inconsistent with the written
        information contained in such documents.

                        (e) IVonyx represents that (i) only the Preferred
        Stockholders are entitled to receive any Shares pursuant to IVonyx's
        Certificate of Incorporation in connection with IVonyx's distribution of
        such Shares; (ii) there are 180 holders of record of its preferred
        stock; (iii) Schedule 4.26(e) hereto is a true, complete and correct
        list of the preferred stockholders of IVonyx (the "Preferred
        Stockholders"); (iv) except as identified on Schedule 4.26(e), each
        Preferred Stockholder is an accredited investor; and (v) except as
        identified on Schedule 4.26(e), each Preferred Stockholder has executed
        an Investment Representation Letter and Lock-Up Agreement and (vi)
        IVonyx has made available a purchaser representative (as defined in
        Regulation D promulgated under the Securities Act) to advise each
        Preferred Stockholder with respect to whether to consent to the sale of
        the Assets and the other transactions contemplated hereby.

                        (f) Each IVonyx Party acknowledges that the Koop Parties
        are entering into this Agreement in reliance upon IVonyx's
        representations and warranties herein, for purposes of establishing a
        valid exemption from the registration requirements of the Securities
        Act."

        13. Section 5.6 is hereby amended by (A) deleting each reference to the
words "Registration Statement" therein and replacing them with the words
"Information Statement" and (B) deleting the words "filed with the SEC and at
the time it becomes effective under the Securities Act" and replacing them with
the words "delivered to the stockholders of IVonyx".

        14. Section 6.10 is hereby amended by deleting the words "Registration
Statement" from the second sentence thereof and replacing them with the words
"Information Statement".

        15. Section 6.11 is hereby deleted in its entirety and replaced with the
following Section 6.11:

                "6.11 Information Statement. As promptly as reasonably
        practicable after the receipt of the Required IVonyx Financial
        Statements, the IVonyx Parties and Parent will prepare the Information
        Statement. The IVonyx Parties and Parent shall cooperate with



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        each other in the preparation of the Information Statement and shall
        promptly supply any information which may be required to be included in
        the Information Statement. As promptly as practicable following
        completion of the Information Statement, IVonyx shall cause the
        Information Statement to be mailed to its stockholders for the purpose
        of obtaining the requisite written consent of the Preferred Stockholders
        for the sale of the Assets and the other transactions contemplated
        hereby."

        16. Section 8.6 is hereby deleted in its entirety and replaced with the
following Section 8.6:

                "8.6 [Reserved]."

        17. Section 9.9 is hereby deleted in its entirety and replaced with the
following Section 9.9:

                "9.9 [Reserved]."

        18. Section 10.8(a) is hereby amended by deleting each reference to the
word "Shares" and replacing it with the words "Escrow Shares".


        19. Article XI is hereby deleted in its entirety and replaced with the
following Article XI:

                                  "ARTICLE XI.

                   REGISTRATION RIGHTS; TRANSFER RESTRICTIONS

                11.1 Certain Definitions. For purposes of this Article XI:

                        (a) Registration. The terms "register," "registered" and
        "registration" refer to a registration effected by preparing and filing
        a registration statement in compliance with the Securities Act, and the
        declaration or ordering of effectiveness of such registration statement.

                        (b) Registrable Securities. The term "Registrable
        Securities" means (i) the Initial Shares that are issued to IVonyx (and
        distributed to IVonyx's Preferred Stockholders) and the Additional
        Shares, if applicable, that are issued to IVonyx's Preferred
        Stockholders, pursuant to Article II hereof and (ii) any shares of
        Common Stock that may be issued as a dividend or other distribution
        (including shares of Common Stock issued in a subdivision and split of
        Parent's outstanding Common Stock) with respect to, or in exchange for,
        or in replacement of, shares of Common Stock described in clause (i) or
        in this clause (ii) of this Section 11.1(b); excluding in all cases,
        however, from the definition of "Registrable Securities" any such shares
        that are: (w) registered under the Securities Act other than pursuant to
        a registration statement filed pursuant to this Agreement; (x) sold by a
        person in a transaction in which rights under this Article XI with
        respect to such shares are not assigned in accordance with the terms of
        this Article XI; (y) sold pursuant to a registration statement filed
        pursuant to this Agreement; or



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        (z) sold pursuant to Rule 144 promulgated under the Securities Act or
        otherwise sold to the public. Only shares of Common Stock shall be
        Registrable Securities. Except as provided in clause (ii) of the first
        sentence of this Section 11.1(b), the term "Registrable Securities" does
        not include any shares of Common Stock that were not issued pursuant to
        Article II.

                        (c) Holder. The term "Holder" means IVonyx or any
        assignee of record of any Registrable Securities to whom rights under
        this Article XI have been duly assigned in accordance with Section 11.9.

                11.2 Piggyback Registration Rights. Parent shall notify all
        Holders of Registrable Securities in writing at least twenty (20) days
        prior to filing any registration statement under the Securities Act for
        purposes of effecting a public offering of Common Stock, excluding
        registration statements (i) relating to any employee benefit plan, (ii)
        on Form S-4 or any successor form relating to a transaction covered by
        Rule 145 promulgated under the Securities Act, (iii) relating to any
        underwritten public offering or any other public offering of securities
        by Parent for capital raising purposes and (iv) filed prior to the first
        anniversary of the Closing Date, and will afford each such Holder an
        opportunity to include in such registration statement all or any part of
        the Registrable Securities then held by such Holder. Each Holder
        desiring to include in any such registration statement all or any part
        of the Registrable Securities held by such Holder shall, within ten (10)
        days after receipt of the above-described notice from Parent, so notify
        Parent in writing, and in such notice shall inform Parent of the number
        of Registrable Securities such Holder wishes to include in such
        registration statement. If a Holder decides not to include all of its
        Registrable Securities in any registration statement thereafter filed by
        Parent, such Holder shall nevertheless continue to have the right to
        include any Registrable Securities in any subsequent registration
        statement or registration statements as may be filed by Parent with
        respect to offerings of its securities, all upon the terms and
        conditions set forth herein.

                11.3 Limitations. Notwithstanding the provisions of Section 11.2
        above, Parent shall not be obligated to effect any registration,
        qualification or compliance of Registrable Securities pursuant to
        Section 11.2 of this Agreement, and the Holders shall not be entitled to
        sell Registrable Securities pursuant to any registration statement filed
        under Section 11.2 of this Agreement, as applicable:

                        (a) if Parent shall furnish to the Holders a certificate
        signed by an officer of Parent stating that, in the good faith judgment
        of such officer, it would be detrimental to Parent and its stockholders
        for such registration statement to be in effect or such sales to be made
        at such time, due, for example, to the existence of a material
        development or potential material development involving Parent which
        Parent would be obligated to disclose in the prospectus contained in the
        registration statement, which disclosure would, in the good faith
        judgment of such officer, be premature or otherwise inadvisable at such
        time or could have a material adverse affect upon Parent and its
        stockholders, in which event Parent will have the right to defer the
        filing of any such registration statement or such sales for a period of
        not more than sixty (60) days after delivery of such



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        certificate to the Holders; provided, however, that Parent may not
        exercise this deferral right more than once in a six month period;

                        (b) if Parent is acquired and Common Stock ceases to be
        publicly traded;

                        (c) in any particular jurisdiction in which Parent would
        be required to qualify to do business or to file a general consent to
        service of process in effecting such registration, qualification or
        compliance, unless Parent is already subject to service of process in
        such jurisdiction;

                        (d) if the SEC refuses to declare such registration
        effective due to the participation of any particular Holder in such
        registration (unless such Holder withdraws all such Holder's Registrable
        Securities from such registration statement); or if the manner in which
        any Registrable Securities are disposed of pursuant to the registration
        statement is not included within the plan of distribution set forth in
        the prospectus for the registration statement; or

                        (e) if the registration statement triggering such
        piggyback registration rights is withdrawn for any reason whatsoever.

                11.4 Shares Otherwise Eligible for Resale. Notwithstanding
        anything herein to the contrary, Parent shall not be obligated to effect
        or continue to keep effective any such registration, registration
        statement, qualification or compliance with respect to the Registrable
        Securities held by any particular Holder:

                        (a) if all the Registrable Securities then held by such
        Holder may be resold by such Holder within a three month period without
        registration under the Securities Act pursuant to the provisions of Rule
        144 promulgated under the Securities Act (or successor provisions), or
        otherwise; or

                        (b) if all Registrable Securities have been registered
        and sold pursuant to a registration effected pursuant to this Agreement
        and/or have been transferred in transactions in which registration
        rights hereunder have not been assigned in accordance with this
        Agreement.

                11.5 Expenses. Parent shall pay all expenses reasonably incurred
        in connection with any registration effected by Parent pursuant to this
        Agreement (excluding brokers' discounts and commissions), including all
        filing, registration and qualification, printers', legal (including, the
        reasonable fees and expenses of one counsel for the Holders as a group)
        and accounting fees. Parent shall reimburse the Holders of Registrable
        Securities being registered pursuant to such registration for the
        reasonable fees and disbursements of not more than one counsel chosen by
        a majority of such Registrable Securities being registered pursuant to
        such registration.

                11.6 Obligations of Parent. Subject to Sections 11.2, 11.3 and
        11.4 above, when required to effect the registration of any Registrable
        Securities under the terms of this Agreement, Parent will, as
        expeditiously as reasonably possible:



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                        (a) furnish to the Holders such number of copies of the
        prospectus included in registration statement and amendments or
        supplements thereto, in conformity with the requirements of the
        Securities Act, and such other documents as they may reasonably request
        in order to facilitate the disposition of the Registrable Securities
        owned by them;

                        (b) notify each Holder of Registrable Securities
        promptly and, if requested by such Holder, confirm such notification in
        writing promptly (i) when a registration statement has become effective
        and when any post-effective amendments and supplements thereto become
        effective, (ii) of any request by the SEC or any state securities
        authority for post-effective amendments and supplements to a
        registration statement has become effective, (iii) of the issuance by
        the SEC or any state securities authority of any stop order suspending
        the effectiveness of a registration statement or the initiation of any
        proceedings for that purpose, (iv) of the receipt by Parent of any
        notification with respect to the suspension of the qualification of the
        Registrable Securities for sale in any jurisdiction or the initiation or
        threatening of any proceeding for such purpose, and (v) of any
        determination by Parent that a post-effective amendment to a
        registration statement would be appropriate;

                        (c) use all reasonable efforts to (i) register and
        qualify the securities covered by such registration statement under such
        other securities or blue sky laws of such jurisdictions in the United
        States as will be reasonably requested by the Holders; and (ii) cause
        such Registrable Securities to be registered with or approved by such
        other governmental agencies or authorities, including the National
        Association of Securities Dealers as may be necessary by virtue of the
        business and operations of Parent; provided, however, that Parent will
        not be required to (A) qualify generally to do business in any
        jurisdiction where it would not otherwise be required to qualify but for
        this paragraph (c), or (B) consent to general service of process in any
        such jurisdiction except as may be required by the Securities Act; and

                        (d) promptly notify each Holder of Registrable
        Securities covered by such registration statement, when a prospectus
        relating thereto is required to be delivered under the Securities Act,
        of the happening of any event as a result of which the prospectus
        included in such registration statement, as then in effect, includes an
        untrue statement of a material fact or omits to state a material fact
        required to be stated therein or necessary to make the statements
        therein not misleading in the light of the circumstances then existing
        and, subject to the provisions of this Agreement, at the request of any
        Holder, prepare and furnish to each Holder of Registrable Securities
        then outstanding a reasonable number of copies of a supplement to or an
        amendment of the prospectus as may be necessary to correct the untrue
        statement or omission.

                11.7 Furnish Information. It shall be a condition precedent to
        the obligations of Parent to take any action pursuant to this Article XI
        that the selling Holders will furnish to Parent such information
        regarding themselves, the Registrable Securities held by them, and the
        intended method of disposition and plan of distribution of such
        Registrable Securities as shall be requested by Parent and to timely
        effect the registration of their Registrable Securities.



                                       10
<PAGE>   11

                11.8 Indemnification.

                        (a) By Parent. To the extent permitted by law, Parent
        will indemnify, defend and hold harmless each Holder against any losses,
        claims, damages, or liabilities (joint or several), including all
        reasonable legal and other expenses reasonably incurred by a Holder to
        which such Holder may become subject under the Securities Act or other
        U.S. federal or state law, insofar as such losses, claims, damages, or
        liabilities (or actions in respect thereof) arise out of or are based
        upon any of the following statements, omissions or violations
        (collectively, a "Violation"):

                                (i) any untrue statement or alleged untrue
        statement of a material fact contained in a registration statement filed
        by Parent pursuant to this Agreement pursuant to which Registrable
        Securities are sold, including any preliminary prospectus or final
        prospectus contained therein or any amendments or supplements thereto;

                                (ii) the omission or alleged omission to state
        in such registration statement, preliminary prospectus or final
        prospectus or any amendments or supplements thereto, a material fact
        required to be stated therein, or necessary to make the statements
        therein not misleading; or

                                (iii) any violation or alleged violation by
        Parent of the Securities Act, the Exchange Act, any U.S. federal or
        state securities law or any rule or regulation promulgated under the
        Securities Act, the Exchange Act or any U.S. federal or state securities
        law in connection with the offering of Registrable Securities covered by
        such registration statement;

                                provided however, that the indemnity agreement
        contained in this Section 11.8(a) shall not apply to amounts paid in
        settlement of any such loss, claim, damage, liability or action if such
        settlement is effected without the written consent of Parent (which
        consent shall not be unreasonably withheld), nor shall Parent be liable
        in any such case for any such loss, claim, damage, liability or action
        to the extent that it arises out of or is based upon a Violation which
        occurs in reliance upon and in conformity with written information
        furnished expressly for use in connection with such registration by such
        Holder.

                        (b) By Selling Holders. To the extent permitted by law,
        (i) each selling Holder will indemnify and hold harmless Parent, each of
        its directors, each of its officers who have signed the registration
        statement, each Person, if any, who controls Parent within the meaning
        of the Securities Act, any underwriter and any other Holder selling
        securities under such registration statement, against any losses,
        claims, damages or liabilities (joint or several) to which Parent or any
        such director, officer, controlling person, underwriter or other such
        Holder may become subject under the Securities Act, the Exchange Act or
        other federal or state law, insofar as such losses, claims, damages or
        liabilities (or actions in respect thereto) arise out of or are based
        upon any Violation, in each case to the extent (and only to the extent)
        that such Violation occurs in reliance upon and in conformity with
        written information furnished by such Holder expressly for use in



                                       11
<PAGE>   12

        connection with such registration; (ii) and each such Holder will
        indemnify and reimburse Parent or any such director, officer,
        controlling person, underwriter or other Holder for any reasonable
        attorneys' fees and other expenses reasonably incurred by Parent or any
        such director, officer, controlling person or other Holder in connection
        with investigating or defending any such loss, claim, damage, liability
        or action, as incurred. Each selling Holder's liability pursuant to this
        Section 11.8(b) shall be limited to an amount equal to the net proceeds
        received by such selling Holder pursuant to sales under the registration
        statement, except in the case of fraud by such Holder.

                        (c) Notice. Promptly after receipt by an indemnified
        party under this Section 11.8 of notice of the commencement of any
        action (including any governmental action) against such indemnified
        party, such indemnified party will, if a claim for indemnification or
        contribution in respect thereof is to be made against any indemnifying
        party under this Section 11.8, deliver to the indemnifying party a
        written notice of the commencement thereof and, if the indemnifying
        party is Parent, Parent shall have the right and obligation to control
        the defense of such action, and if Parent fails to defend such action it
        shall indemnify and reimburse the selling Holders for any reasonable
        attorneys' fees and other expenses reasonably incurred by them in
        connection with investigating or defending such action; provided,
        however, that: (i) Parent shall also have the right, at its option, to
        assume and control the defense of any action with respect to which
        Parent or any person entitled to be indemnified by the selling Holders
        under Section 11.8(b) is entitled to indemnification from the selling
        Holders; (ii) the indemnified party or parties shall have the right to
        participate at its own expense in the defense of such action and (but
        only to the extent agreed in writing with Parent and any other
        indemnifying party similarly noticed) to assume the defense thereof with
        counsel mutually satisfactory to the parties; and (iii) an indemnified
        party shall have the right to retain its own counsel, with the fees and
        expenses of such counsel to be paid by the indemnifying party, if
        representation of such indemnified party by the counsel retained by the
        indemnifying party would be inappropriate due to an actual or potential
        conflict of interests between such indemnified party and any other party
        represented by such counsel in such proceeding. The failure of an
        indemnified party to deliver written notice to the indemnifying party
        within a reasonable time of the commencement of any such action, if
        prejudicial to the ability of the indemnifying party to defend such
        action, shall relieve such indemnifying party of any liability to the
        indemnified party under this Section 11.8, but the omission so to
        deliver written notice to the indemnifying party will not relieve the
        indemnifying party of any liability that it may have to any indemnified
        party otherwise than under this Section 11.8.

                        (d) Defect Eliminated in Final Prospectus. The foregoing
        indemnity agreements of Parent and the Holders are subject to the
        condition that, insofar as they relate to any Violation made in a
        preliminary prospectus but eliminated or remedied in the amended or
        supplemented prospectus on file with the SEC and effective at the time
        the sale of Registrable Securities under such registration statement
        occurs (the "Amended Prospectus"), such indemnity agreement shall not
        inure to the benefit of any person if a copy of the Amended Prospectus
        was furnished to the indemnified party and was not furnished to the
        person asserting the loss, liability, claim or damage in the action
        giving



                                       12
<PAGE>   13

        rise to indemnity claims under this Section 11.8, at or prior to the
        time such action is required by the Securities Act.

                11.9 Assignment of Registration Rights. Notwithstanding anything
        herein to the contrary, the rights of a Holder under Article XI may be
        assigned only with Parent's express prior written consent, which may be
        withheld in Parent's sole discretion; provided, however, that the rights
        of a Holder under Article XI may be assigned without Parent's express
        prior written consent to (i) any stockholder of IVonyx to which IVonyx
        distributes Registrable Securities in accordance with Article II hereof
        or (ii) any Permitted Transferee of such stockholder in accordance with
        Section 11.10 or (iii) after the termination of the restrictions on
        transfer set forth in Section 11.10, any transferee of Holder that
        acquires at least $25,000 worth of Common Stock valued as of the date of
        transfer; provided, however, that in all cases it shall be a condition
        to such assignment that the assignee execute an agreement stating that
        the assignee is receiving and holding such shares of Common Stock
        subject to the provisions of this Section 11.9, and there shall be no
        further assignment of the rights of a Holder under this Article XI
        except in accordance with this Section 11.9. Any attempt to assign any
        rights of a Holder under Article XI without Parent's express prior
        written consent in a situation in which such consent is required by this
        Section shall be null and void and without effect. Subject to the
        foregoing restrictions, all rights, covenants and agreements in Article
        XI by or on behalf of the parties hereto will bind and inure to the
        benefit of the respective permitted successors and assigns of the
        parties hereto.

                11.10 Restrictions on Transfer.

                        (a) For a period of one (1) year from the Closing Date,
        IVonyx shall not (i) offer, pledge, sell, contract to sell, sell any
        option or contract to purchase, purchase any option or contract to sell,
        grant any option, right or warrant to purchase, or otherwise transfer or
        dispose of, directly or indirectly, any Initial Shares (as defined in
        Section 2.3) or any securities convertible into or exercisable or
        exchangeable for Initial Shares (including, without limitation,
        securities convertible into or exercisable or exchangeable for Initial
        Shares that may be deemed to be beneficially owned by IVonyx, any such
        stockholder or any Permitted Transferee in accordance with the rules and
        regulations of the SEC), or (ii) enter into any swap or other
        arrangement that transfers all or a portion of the economic consequences
        associated with the ownership of any Initial Shares (any such
        transaction, a "Transfer"); provided, however, that IVonyx may Transfer
        Initial Shares in accordance with Article II to any Preferred
        Stockholder of IVonyx that has completed, executed and delivered to
        Parent an Investment Representation Letter and Lock-Up Agreement.
        Following the expiration of the one (1) year period, to the extent
        IVonyx holds any Initial Shares, such Initial Shares may only be
        Transferred by IVonyx pursuant to an effective registration statement
        under the Securities Act or in a transaction exempt from the
        registration requirements of the Securities Act in accordance with this
        Section 11.10. Unless there is an effective registration statement under
        the Securities Act covering the Transfer of the Initial Shares,
        following the expiration of such one (1) year period, IVonyx may not
        Transfer any Initial Shares without first notifying Purchaser of its
        intention to effect such Transfer, which notice must be accompanied by a
        written opinion of legal counsel reasonably satisfactory to Parent to
        the effect that the proposed



                                       13
<PAGE>   14

        Transfer of the Initial Shares may be effected without registration
        under the Securities Act (it being understood that any holders subject
        to Rule 145 Letter Agreements shall be subject to the terms of the Rule
        145 Letter Agreements).

                        (b) Notwithstanding the preceding paragraph, (i) if a
        potential transferor of any Shares is an individual, such Person may
        transfer any or all of such Shares in private transactions (A) to or for
        the benefit of members of such Person's immediate family, (B) to any
        trust, limited liability company or partnership for the direct or
        indirect benefit of (or directly or indirectly owned by) such Person or
        such Person's immediate family or (C) by gift, will or intestacy; or
        (ii) if a potential transferor of any Shares is an entity or a trust,
        such Person may transfer any or all of such Shares in private
        transactions (A) to entities controlling, controlled by or under common
        control with such Person, or (B) as a distribution to partners, members
        or stockholders of such Person (each, a "Permitted Transfer" and each
        transferee, a "Permitted Transferee"); provided, however, that in all
        cases it shall be a condition to the Permitted Transfer that the
        Permitted Transferee execute an agreement stating that the Permitted
        Transferee is receiving and holding such Shares subject to the
        provisions of this Article XI, and there shall be no further transfer of
        such Shares except in accordance with this Article XI; provided further,
        that if any such transfer is not made pursuant to an effective
        registration statement, in all cases it shall be a condition to the
        Permitted Transfer that Parent shall have received prior notice of such
        transfer accompanied by a written opinion of legal counsel reasonably
        satisfactory to Parent to the effect that the proposed transfer may be
        effected without registration under the Securities Act; provided further
        that if the Permitted Transferee may be deemed an "affiliate" of Parent
        (as that term is used in Rule 145 promulgated under the Securities Act),
        such Permitted Transferee shall also execute a Rule 145 Letter
        Agreement.

                        (c) Notwithstanding the foregoing, in no event shall
        IVonyx transfer the Contingent Shares Right to any Person other than to
        the Preferred Stockholders to which IVonyx distributed Non-Escrowed
        Shares pursuant to Section 2.3 contemporaneous with the distribution of
        such Non-Escrowed Shares and in proportion to the relative number of
        Non-Escrowed Shares distributed to such Preferred Stockholders, and in
        no event shall any Preferred Stockholders to which a portion of the
        Contingent Shares Right is so transferred have the right to Transfer the
        Contingent Shares Right to any Person, including Permitted Transferees,
        and any purported Transfer of the Contingent Shares Right prohibited by
        this Section 11.10(c) shall be null and void.

                        (d) IVonyx agrees, and each Preferred Stockholder and
        Permitted Transferee shall agree as a condition to the transfer of
        Shares to such Person, that Parent may, and that such Person will, (a)
        with respect to any Shares that are subject to the restrictions set
        forth in Article XI for which such Person is the record holder, cause
        the transfer agent for Parent to note stop transfer instructions with
        respect to such shares on the transfer books and records of Parent and
        (b) with respect to any Shares that are subject to the restrictions set
        forth in Article XI for which such Person is the beneficial holder but
        not the record holder, cause the record holder of such Shares to cause
        the transfer agent for Parent to note stop transfer instructions with
        respect to such Shares on the transfer books and records of Parent.
        IVonyx acknowledges, and each stockholder of



                                       14
<PAGE>   15

        IVonyx and Permitted Transferee of IVonyx shall acknowledge as a
        condition to the transfer of Shares to such Person, that each
        certificate representing the Shares shall bear a legend evidencing the
        provisions of this Article XI. Without limiting the restrictions herein,
        any sale, transfer or other disposition of the Shares by IVonyx, a
        stockholder of IVonyx or any Permitted Transferee shall remain at all
        times subject to applicable securities laws, including without
        limitation the resale restrictions imposed by Rules 144 and 145
        promulgated under the Securities Act."

        20. The Exhibits to the Purchase Agreement are hereby amended by
inserting the exhibit attached hereto as Exhibit E thereof.

        21. Unless otherwise indicated, all references in this Amendment to
designated "sections" are to the designated Sections of the Purchase Agreement.

        22. Except as modified by the foregoing, the terms and conditions of the
Purchase Agreement shall remain in full force and effect.

        23. This Amendment may be executed in one or more counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

        24. This Amendment shall be construed, interpreted and the rights of the
Parties determined in accordance with the laws of the State of California
(without giving effect to its conflicts of law principles).


                            [Signature Page Follows]



                                       15
<PAGE>   16

                IN WITNESS WHEREOF, the Parties hereto have caused this
Amendment to be duly executed by their respective authorized officers as of the
day and year first above written.

                                       IVONYX:

                                       IVONYX GROUP SERVICES, INC.


                                       By:
                                          --------------------------------------
                                       Name:  G. Peter Molloy, Jr.
                                            ------------------------------------
                                       Title: Chief Executive Officer
                                             -----------------------------------


                                       IVONYX SUB:

                                       IVONYX, INC.


                                       By:
                                          --------------------------------------
                                       Name:  G. Peter Molloy, Jr.
                                            ------------------------------------
                                       Title: Chief Executive Officer
                                             -----------------------------------


                                       ACQUISITION SUB:

                                       DRKOOP LIFECARE, INC.


                                       By:
                                          --------------------------------------
                                       Name: Edward A. Cespedes
                                            ------------------------------------
                                       Title: Vice President and Secretary
                                             -----------------------------------


                                       PARENT:

                                       DRKOOP.COM, INC.


                                       By:
                                          --------------------------------------
                                       Name:  Edward A. Cespedes
                                            ------------------------------------
                                       Title: President
                                             -----------------------------------



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