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                                                                   Exhibit 10.90

                             EMPLOYMENT AGREEMENT

          THIS EMPLOYMENT AGREEMENT (the "Agreement") is made and entered into
                                          ---------
as of October 24, 2000, by and between drkoop.com, Inc., a Delaware corporation
(the "Company"), and William H. Carlson ("Employee").
      -------                             --------

                                   RECITALS
                                   --------

          WHEREAS, the Company desires to obtain the services of the Employee as
an Executive Vice President in the manner hereinafter specified in its business,
and also to make provisions for the payment of compensation to the Employee for
such services; and

          WHEREAS, the Employee is willing to be employed by the Company as an
Executive Vice President and to perform the duties incident to such employment
upon the terms and subject to the conditions hereinafter set forth;

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

                                   AGREEMENT
                                   ---------

          NOW, THEREFORE, in consideration of the mutual promises and agreements
contained herein, and for other good and valuable consideration, the receipt of
which is hereby acknowledged, the parties hereto agree as follows:

          1.  Start Date. The "Term of Employment" (as defined herein) shall
              ----------
commence as of the date hereof, which date shall be referred to herein as the
"Start Date."
-----------

          2.  Position and Duties.
              -------------------

              (a) The Company hereby employs Employee as an Executive Vice
President of the Company commencing as of the Start Date for the Term of
Employment. In this capacity, Employee shall devote his best efforts to the
performance of the services customarily incident to such office and position and
to such other services of as may be requested by the President or Chief
Executive Officer of the Company which may include services for one or more
other subsidiaries of the Company. Employee, in his capacity as an employee of
the Company, shall be responsible to and obey the reasonable and lawful
directives of the Chief Executive Officer and President of the Company. Employee
shall report to the President or any other person designated by the President,
and Employee shall have such authority and duties as are customary in such
position.

              (b) Employee shall devote all of his business time and attention
to such duties, except for sick leave, reasonable vacations, and excused leaves
of absence as more particularly provided herein. Notwithstanding the foregoing,
to the extent that the time so spent does not conflict with the Company's
business, Employee may devote time to personal and family investments. The
existence of such a conflict shall be determined in good faith by the

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Board of Directors of the Company (the "Board"). Employee shall use his best
                                        -----
efforts during the Term of Employment to protect, encourage, and promote the
interests of the Company.

          3.  Compensation.
              ------------

              (a) Base Salary. The Company shall pay to Employee during the Term
                  -----------
of Employment a base salary at the rate of Two Hundred Thousand Dollars
($200,000) per calendar year. Such salary shall be payable at least semi-monthly
in accordance with the Company's normal payroll procedures. (Employee's annual
salary, as set forth above or as it may be increased from time to time in the
Board's sole discretion, shall be referred to hereinafter as the "Base
                                                                  ----
Salary.").
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              (b) Performance Bonus. In addition to the compensation otherwise
                  -----------------
payable to Employee pursuant to this Agreement, Employee shall be eligible to
receive additional annual bonuses to the extent, if any, approved by the Board
in its sole discretion.

              (c) Options.  The Company will grant you a stock options to
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purchase up to 1,000,000 shares of the Company's common stock (the "Options")
                                                                    -------
upon the terms and subject to the conditions set forth in the Company's 2000
Non-Qualified Stock Option Plan and to be documented in a customary stock option
agreement pursuant to such Plan. The stock option agreement with respect to the
Options shall provide for an exercise price per share for such Options of
$0.9062 and that the Options vest according to the following schedule: Options
to purchase 50,000 shares shall vest upon the date of grant; Options to purchase
316,667 shares shall vest upon the first anniversary of the Start Date; Options
to purchase 316,666 shares shall vest on the second anniversary of the Start
Date; and the remaining Options to purchase 316,666 shares shall vest on the
third anniversary of the Start Date. The stock option agreement with respect to
the Options shall also provide that (i) in the event of a Change in Control, 50%
of any unvested Options as of the date of such termination shall immediately
vest and become exercisable and (ii) in the event that Employee is terminated
without Cause (as defined below) or terminates his employment for Good Reason
(as defined below), any unvested Options as of the date of such termination
shall immediately vest and become exercisable. For purposes of the Options,
"Change in Control" shall mean: (i) any sale, merger, consolidation, tender
 -----------------
offer or similar acquisition of shares, or other transaction or series of
related transactions (each a "Transaction") as a result of which at least a
                              -----------
majority of the voting power of Company is not held, directly or indirectly, by
the persons or entities who held the Company's securities with voting power
before such Transaction; (ii) a sale or other disposition of all or
substantially all of the Company's assets, whether in one transaction or a
series of related transactions; or (iii) individuals who on the date hereof
constitute Company's Board of Directors and any new director (other than a
director designated by a person or entity who has entered into an agreement to
effect a transaction described in clause (i) or (ii) above) whose nomination
and/or election to the Board was approved by a vote of at least a majority of
the directors then still in office who either were directors on the date hereof
or whose election or nomination for election was previously so approved, cease
for any reason to constitute a majority of the Company's or such parent's Board
of Directors.  Employee acknowledges that as of the date of this Agreement there
will be more shares reserved for issuance than are authorized and unissued under
the Company's

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Certificate of Incorporation and waives any breach hereof or of the related
option agreement and option plan if remedied within 9 months of the date of this
Agreement; provided that if the Company is unable to deliver shares issuable
           --------
upon exercise of vested options following a Change in Control or Employee's
termination of employment without Cause or for Good Reason within 9 months of
the date of this Agreement, then, upon such exercise, the Company shall deliver
to Employee cash equal to the excess of the fair market value of the shares
issuable upon such exercise over the exercise price, within 10 business days of
Employee's delivery of his notice of exercise.

          4.  Benefits.  During the Term of Employment:
              --------

              (a) Employee shall be eligible to participate in any life, health
and long-term disability insurance programs, pension and retirement programs,
stock option and other incentive compensation programs, and other fringe benefit
programs made available to executive employees of the Company from time to time,
and Employee shall be entitled to receive such other fringe benefits as may be
granted to him from time to time by the Board. Nothing herein, however, is
intended or shall be construed to require the Company to institute or continue
all, or any particular, plan or benefits.

              (b) Employee shall be allowed four (4) weeks vacations with pay,
and leaves of absence with pay in accordance with the Company's policies in
effect from time to time.

              (c) The Company shall reimburse Employee in accordance with the
policies of the Company, as adopted and amended from time to time, for
reasonable and necessary business expenses incurred in performing Employee's
duties and promoting the business of the Company, including, cellular telephone,
travel and lodging expenses; provided Employee shall, as a condition of such
reimbursement, submit verification of the nature and amount of such expenses in
accordance with the business expense reimbursement policies from time to time
adopted by the Company.

          5.  Term; Termination of Employment.  As used herein, the phrase "Term
              -------------------------------                               ----
of Employment" shall mean the period commencing on the Start Date and ending one
-------------
(1) year from the Start Date; provided that as of the expiration date of such
initial one (1) year Term of Employment and (ii) if applicable, any Renewal
Period (as defined below), the Term of Employment shall automatically be
extended for one (1) year periods (each a "Renewal Period") unless either the
                                           --------------
Company or Employee provides two (2) months notice to the contrary prior to the
end of the Term of Employment or applicable Renewal Period.  Notwithstanding the
foregoing, the Term of Employment shall expire on the first to occur of the
following:

          (a) Termination by the Company Without Cause.  Notwithstanding
              ----------------------------------------
anything to the contrary in this Agreement, whether express or implied, the
Company may, at any time, terminate Employee's employment for any reason other
than Cause (as defined below) by giving Employee at least thirty (30) days prior
written notice of the effective date of termination.  In the event Employee's
employment hereunder is terminated by the Company other than for Cause, Employee
shall be entitled to receive his Base Salary as he would have

                                       3
<PAGE>

received such amounts during the period commencing on the effective date of such
termination and ending six (6) months after such date of termination, whether
during the initial Term of Employment, a Renewal Period or otherwise (such
period hereinafter referred to as the "Salary Continuation Period"), as if
                                       --------------------------
Employee were still employed hereunder during the Salary Continuation Period;
provided that the Company's election not to extend the Term of Employment for
--------
any Renewal Period shall be treated as a termination by the Company without
Cause.

          (b) Termination for Cause.  The Company shall have the right to
              ---------------------
terminate Employee's employment at any time for Cause (as defined below) by
giving Employee written notice of the effective date of termination (which
effective date may, except as otherwise provided below, be the date of such
notice).  If the Company terminates Employee's employment for Cause, Employee
shall be paid his unpaid Base Salary through the date of termination, and the
Company shall have no further obligation hereunder from and after the effective
date of termination and shall have all other rights and remedies available under
this or any other agreement and at law or in equity.

          For purposes of this Agreement, "Cause" shall mean:
                                           -----

              (i)   theft, forgery, fraud, misappropriation, embezzlement, moral
     turpitude or other act of material misconduct against the Company or any of
     its affiliates;

              (ii)  fraudulent or willful and material misrepresentations or
     concealments on any written reports submitted to the Company or any of its
     affiliates;

              (iii) Employee's violation of the Company's substance abuse
     policy;

              (iv)  gross negligence or material misconduct in the performance
     of the duties of Employee required hereunder or his habitual neglect
     thereof;

              (v)   a material failure by the Employee to follow or comply with
     the lawful directives of the Board of Directors of the Company;

              (vi)  a material breach by Employee of the provisions of this
     Agreement or other agreements with the Company;

              (vii) willful and knowing violation of any rules or regulations of
     any governmental or regulatory body, which is or is reasonably expected to
     be materially injurious to the financial condition of the Company;

              (viii)Employee's conviction of, or plea of nolo contendere to, any
     felony or to any crime or offense causing substantial harm to the Company
     or any of its affiliates (whether or not for personal gain) or

                                       4
<PAGE>

          involving acts of theft, forgery, fraud, misappropriation,
          embezzlement, moral turpitude or similar conduct;

              (ix)  Employee shall become associated with any company in the
          tobacco industry;

              (xi)  a material violation of any fiduciary duty owed to the
          Company; or

              (xii) engagement in any act (including, but not limited to,
          unlawful discriminatory conduct) that results in substantial injury to
          the reputation, business or business relationships of the Company or
          that, in each case, has subjected, or if generally known would
          subject, the Company to public ridicule or embarrassment.

          provided, however, that in the case of the foregoing clauses (iv), (v)
and (vi) Employee shall have been informed, in writing, of such material failure
referred to in the foregoing clauses (iv), (v) and (vi) and provided with a
reasonable opportunity to cure such material failure, if such failure is subject
to cure (if such failure is subject to cure, "reasonable opportunity to cure"
shall mean a period of thirty (30) days).

          (c) Resignation for Good Reason.  Employee may terminate his
              ---------------------------
employment for Good Reason (as defined below) by giving the Company at least
thirty (30) days prior written notice of the effective date of termination.  In
the event Employee's employment hereunder is terminated by Employee for Good
Reason, Employee shall be entitled to receive his Base Salary as he would have
received such amounts during the Salary Continuation Period, whether during the
initial Term of Employment, a Renewal Period or otherwise, as if Employee were
still employed hereunder during the Salary Continuation Period.

              For purposes of this Agreement, "Good Reason" shall mean:
                                               -----------

                   (i) (a) the assignment of Employee without his consent to a
        position, responsibilities or duties of a materially lesser status or
        degree of responsibility than his position, responsibilities or duties
        at the Start Date which remains uncured for at least 30 days after
        receipt of notice thereof given by Employee; or

                   (ii) any material breach by the Company in performing its
        obligations hereunder which remains uncured for at least 30 days after
        receipt of notice thereof given by Employee.

          (d) Termination on Account of Death.  In the event of Employee's death
              -------------------------------
while in the employ of the Company, his employment hereunder shall terminate on
the date of his death and Employee shall be paid his unpaid Base Salary through
the date of termination.  In addition, any other benefits payable on behalf of
Employee shall be determined under the

                                       5
<PAGE>

Company's insurance and other compensation and benefit plans and programs then
in effect in accordance with the terms of such programs.

              (e) Termination on Account of Disability.  To the extent not
                  ------------------------------------
prohibited by The Americans With Disabilities Act of 1990, if, as a result of
Employee's incapacity due to physical or mental illness (as determined in good
faith by a physician acceptable to the Company and Employee), Employee is unable
to substantially render to the Company the services required under this
Agreement for more than ninety (90) days out of any consecutive one hundred and
eighty (180) day period or if a physician acceptable to the Company advises the
Company that it is likely that Employee will be unable to return to the
performance of his duties for more than ninety (90) days out of any consecutive
one hundred and eighty (180) day period his employment may be terminated for
"Disability."  During any period that Employee fails to perform his duties with
 ----------
the Company as a result of incapacity due to physical or mental illness, he
shall continue to receive his Base Salary and other benefits provided hereunder,
together with all compensation payable to him under the Company's disability
plan or program or other similar plan during such period, until Employee's
employment hereunder is terminated pursuant to this subparagraph (e).
Thereafter, Employee's benefits shall be determined under the Company's
retirement, insurance, and other compensation and benefit plans and programs
then in effect, in accordance with the terms of such programs, and the Company
shall cease to be obligated to pay the Employee a Base Salary (other than any
amounts owed to the Employee at the time of such termination).

          6.  Confidential Information, Non-Solicitation and Non-Competition.
              --------------------------------------------------------------

              (a) During the Term of Employment and thereafter, Employee shall
not, except as may be required to perform his duties hereunder or as required by
applicable law, disclose to others or use, whether directly or indirectly, any
Confidential Information regarding the Company. "Confidential Information"
                                                 ------------------------
shall mean information about the Company, its subsidiaries and affiliates, and
their respective clients and customers that is not available to the general
public and that was learned by Employee in the course of his employment by the
Company, including, but not limited to, any proprietary knowledge, trade
secrets, data, formulae, information, and client and customer lists and all
papers, resumes, records (including computer records) and the documents
containing such Confidential Information.  Employee acknowledges that such
Confidential Information is specialized, unique in nature and of great value to
the Company, and that such information gives the Company a competitive
advantage.  This confidentiality covenant has no temporal, geographic or
territorial restriction.  Upon the termination of his employment for any reason
whatsoever, Employee shall promptly deliver to the Company all documents,
computer tapes and disks (and all copies thereof) containing any Confidential
Information, and any other tangible property of the Company which has been
produced by, received by or otherwise submitted to the Employee during or prior
to the Term of Employment.

              (b) By and in consideration of Employee's employment hereunder and
the payments to be made and benefits to be provided by the Company hereunder and
further in consideration of Employee's exposure to the proprietary information
of the Company, Employee agrees that; provided that there has not been any
                                      --------
material breach by the Company in performing

                                       6
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its obligations hereunder which remains uncured for at least 30 days after
receipt of written notice thereof given by Employee, (i) during the Term of
Employment and thereafter during the Consulting Term, Employee shall not,
directly or indirectly in any manner or capacity (e.g., as an advisor,
principal, agent, partner, officer, director, shareholder, employee, member of
any association or otherwise) engage in, work for, consult, provide advice or
assistance or otherwise participate in any activity which is competitive with
the Business of the Company (it being understood that this Section 6(b) shall
not prohibit Employee from working for, consulting, providing advice or other
assistance to or otherwise participating in a business (an "Other Company") that
engages in the Business but whose principal line of business is not the Business
so long as Employee does not work for, consult, provide advice or other
assistance to (including, without limitation, by way of promotion or
endorsement) or otherwise participate in any aspect of the Business conducted or
proposed to be conducted by the Other Company) and (ii) during the Consulting
Term, Employee shall provide consulting services to the Company upon reasonable
request by the Company; provided, however, that Employee shall not be required
to provide any consulting services that would interfere with Employee's other
business or employment endeavors. For purposes of this Agreement, the "Business"
shall mean any specific business activity conducted by the Company or any of its
subsidiaries or proposed to be conducted thereby at the time of the Employee's
termination pursuant to this Agreement. Employee further agrees that during such
period he will not assist or encourage any other person in carrying out any
activity that would be prohibited by the foregoing provisions of this Section 6
if such activity were carried out by Employee and, in particular, Employee
agrees that he will not induce any employee of the Company to carry out any such
activity; provided, however, that the "beneficial ownership" by Employee, either
individually or as a member of a "group," as such terms are used in Rule 13d of
the General Rules and Regulations under the Exchange Act, of not more than one
percent (1%) of the voting stock of any publicly held corporation shall not be a
violation of this Agreement. For purposes of this Agreement, the "Consulting
                                                                  ----------
Term" shall mean the period that the Employee is receiving payments under this
----
Agreement in accordance with the terms hereof (with the Company having
reasonable opportunity to cure any breaches of its payment obligations
hereunder); provided, however, that the Company, in its sole discretion, shall
have the right, upon written notice to Employee prior to the date upon which
payments to Employee under this Agreement are to cease, to extend the Consulting
Term for an additional period of time to be determined in the sole discretion of
the Company which shall not exceed one (1) year or, in the event that the
Employee's employment was terminated pursuant to Section 5(a) or Section 5(c),
six (6) months after the end of the Salary Continuation Period. During any such
extension of the Consulting Term, the Company shall continue to pay Employee one
hundred percent (100%) of his Base Salary, in accordance with the Company's
normal payroll practices with respect to base salary, at the rate in effect on
the date of Employee's termination of employment. It is further expressly agreed
that the Company will or would suffer irreparable injury if Employee were to
compete with the Company or any subsidiary or affiliate of the Company in
violation of this Agreement and that the Company would by reason of such
competition be entitled to injunctive relief in a court of appropriate
jurisdiction, and Employee further consents and stipulates to the entry of such
injunctive relief in such a court prohibiting Employee from competing with the
Company or any subsidiary or affiliate of the Company in violation of this
Agreement. Employee agrees that the terms of this paragraph shall not prevent
the Company and/or its subsidiaries from pursuing any other available remedies
for any breach

                                       7
<PAGE>

or threatened breach thereof, including but not limited to the recovery of
damages from the Employee. Employee and the Company further agree that the
provisions of the covenants contained in this Agreement are reasonable and
necessary to protect the businesses of the Company and its subsidiaries because
of Employee's access to Confidential Information and his material participation
in the operation of such businesses. Employee hereby acknowledges that due to
the global aspects of the Company's and its subsidiaries' businesses and
competitors, it would not be appropriate to include any geographic limitation in
this Agreement.

          (c) During the period that Employee is receiving payments under this
Agreement, Employee shall not, directly or indirectly, influence or attempt to
influence suppliers of the Company or any of its subsidiaries or affiliates, to
divert their business to any competitor of the Company.

          (d) Employee recognizes that he will possess confidential information
or trade secrets about other employees of the Company relating to their
education, experience, skills, abilities, compensation and benefits, and
interpersonal relationships with customers of the Company (the "Employee
                                                                --------
Information").  Employee recognizes that the Employee Information he will
-----------
possess is not generally known, is of substantial value to the Company in
developing its business and in securing and retaining customers, and will be
acquired by him because of his business position with the Company.  Employee
agrees that, during the period that Employee is receiving payments under this
Agreement and for one (1) year thereafter, Employee will not, directly or
indirectly, solicit or recruit any employee of the Company for the purpose of
being employed by Employee or by any competitor of the Company on whose behalf
he is acting as an agent, representative or employee and that he will not convey
any Employee Information to any other person.

          (e) If it is determined by a court of competent jurisdiction in any
state that any restriction in this Section 6 is excessive in duration or scope
or is unreasonable or unenforceable under the laws of that state, it is the
intention of the parties that such restriction may be modified or amended by the
court to render it enforceable to the maximum extent permitted by the law of
that state.

      7.  Designated Beneficiary.  In the event of the death of Employee while
          ----------------------
in the employ of the Company, or at any time thereafter during which amounts
remain payable to Employee under Section 5, such payments (other than the right
to continuation of welfare benefits) shall thereafter be made to such person or
persons as Employee may specifically designate (successively or contingently) to
receive payments under this Agreement following Employee's death by filing a
written beneficiary designation with the Company during Employee's lifetime.
Such beneficiary designation shall be in such form as may be prescribed by the
Company and may be amended from time to time or may be revoked by Employee
pursuant to written instruments filed with the Company during his lifetime.
Beneficiaries designated by Employee may be any natural or legal person or
persons, including a fiduciary, such as a trustee or a trust or the legal
representative of an estate. Unless otherwise provided by the beneficiary
designation filed by Employee, if all of the persons so designated die before
Employee on the

                                       8
<PAGE>

occurrence of a contingency not contemplated in such beneficiary designation,
then the amounts payable under this Agreement shall be paid to Employee's
estate.

          8.  Taxes.  All payments to be made to Employee under this Agreement
              -----
will be subject to any applicable withholding of federal, state and local income
and employment taxes.

          9.  Resolution of Disputes.  Notwithstanding anything herein to the
              ----------------------
contrary, in the event that there shall be a dispute among the parties arising
out of or relating to this Agreement or the breach thereof, other than, at the
option of Company, Section 6, the parties agree that such dispute shall be
resolved by final and binding arbitration in New York, New York in accordance
Commercial Arbitration Rules then in effect of JAMS/ENDISPUTE.  Depositions may
be taken and other discovery may be obtained during such arbitration proceedings
to the same extent as authorized in civil judicial proceedings.  Any award
issued as a result of such arbitration shall be final and binding between the
parties thereto, and shall be enforceable by any court having jurisdiction over
the party against whom enforcement is sought.  The fees and expenses of such
arbitration (including, but not limited to, reasonable attorneys' fees) or any
action to enforce an arbitration award shall be paid by the party that does not
prevail in such arbitration.

          10.  Attorneys' Fees.  Should either party hereto or their successors
               ---------------
retain counsel for the purpose of enforcing, or preventing the breach of, any
provision hereof, including, but not limited to, by instituting any action or
proceeding in arbitration or a court to enforce any provision hereof or to
enjoin a breach of any provision of this Agreement, or for a declaration of such
party's rights or obligations under the Agreement, or for any other remedy,
whether in arbitration or in a court of law, then each party shall bear their
own costs and expenses incurred thereby, including, but not limited to,
reasonable fees and expenses of attorneys and expert witnesses, including costs
of appeal.

          11.  Limitation of Liabilities.  If Employee is awarded any damages as
               -------------------------
compensation for any breach or action related to this Agreement, a breach of any
covenant contained in this Agreement (whether express or implied by either law
or fact), or any other cause of action based in whole or in part on any breach
of any provision of this Agreement, such damages shall be limited to contractual
damages and shall exclude (i) punitive damages, and (ii) consequential and/or
incidental damages (e.g., lost profits and other indirect or speculative
damages). The maximum amount of damages that Employee may recover for any reason
shall be the amount equal to all amounts owed (but not yet paid) to Employee
pursuant to this Agreement through its natural term or through any period for
which severance is due pursuant to Section 5 hereof.

          12.  Miscellaneous.  This Agreement shall also be subject to the
               -------------
following miscellaneous considerations:

               (a) Representations and Warranties.
                   ------------------------------

                                       9
<PAGE>

                    (i)  Employee represents and warrants to the Company that he
has the authorization, power and right to deliver, execute and fully perform his
obligations under this Agreement in accordance with its terms. Employee further
represents and warrants that this Agreement does not require any authorization,
consent, approval, exemption or other action by any other party and does not (A)
conflict with or result in the breach of the terms, conditions or provisions of,
(B) constitute a default under, or (C) result in a violation of any agreement,
instrument, order, judgment or decree to which Employee is subject. Employee
will, to the fullest extent permitted by applicable law, as from time to time in
effect, indemnify the Company and hold the Company harmless for any breach of
the representations set forth in this subparagraph (i).

                    (ii) The Company represents and warrants to Employee that it
has the authorization, power and right to deliver, execute and fully perform its
obligations under this Agreement in accordance with its terms. The Company
further represents and warrants that this Agreement does not require any
authorization, consent, approval, exemption or other action by any other party
and does not (A) conflict with or result in the breach of the terms, conditions
or provisions of, (B) constitute a default under, or (C) result in a violation
of any agreement, instrument, order, judgment or decree to which the Company is
subject. The Company will, to the fullest extent permitted by applicable law, as
from time to time in effect, indemnify Employee and hold Employee harmless for
any breach of its representations set forth in this subparagraph (ii).

               (b)  Divisibility of the Agreement.  If any provision of this
                    -----------------------------
Agreement or any portion thereof is declared invalid, illegal, or incapable of
being enforced by any court of competent jurisdiction, the remainder of such
provisions and all of the remaining provisions of this Agreement shall continue
in full force and effect.

               (c)  Choice of Law.  This Agreement shall be construed,
                    -------------
interpreted and the rights of the parties determined in accordance with the
internal laws of the State of California without reference to the choice of law
provisions of such State's law, except with respect to matters of law concerning
the internal corporate affairs of any corporate entity which is a party to or
the subject of this Agreement, and as to those matters of the law the
jurisdiction under which the respective entity derives its powers shall govern,
and to the extent governed by federal law.

               (d)  Assignment.  The Company may assign this Agreement to any
                    ----------
direct or indirect subsidiary or parent of the Company or joint venture in which
the Company has an interest, or any successor (whether by merger, consolidation,
purchase or otherwise) to all or substantially all of the stock, assets or
business of the Company and this Agreement shall be binding upon and inure to
the benefit of such successors and assigns. The duties and covenants of Employee
under this Agreement, being personal, may not be delegated. Except as expressly
provided herein, Employee may not sell, transfer, assign, or pledge any of his
rights or interests pursuant to this Agreement.

                                       10
<PAGE>

               (e)  No Abrogation.  Any rights of Employee hereunder shall be in
                    -------------
addition to any rights Employee may otherwise have under benefit plans,
agreements, or arrangements of the Company to which he is a party or in which he
is a participant, including, but not limited to, any Company-sponsored employee
benefit plans.  Provisions of this Agreement shall not in any way abrogate
Employee's rights under such other plans, agreements, or arrangements.

               (f)  Notice.  For the purposes of this Agreement, notices,
                    ------
demands and all other communications provided for in this Agreement shall be in
writing and shall be deemed to have been duly given when personally delivered or
one day after delivery to an overnight air courier guaranteeing next day
delivery, addressed as follows:

          If to Employee:           William H. Carlson
          --------------
                                    2002 Turnberry Circle
                                    Glenmoore, PA 19343

          If to the Company:        drkoop.com, Inc.
          -----------------
                                    7000 North Mopac, Suite 400
                                    Austin, Texas 78731
                                    Attention:  Board of Directors

          With copies to:           Latham & Watkins
          --------------
                                    633 W. Fifth Street, Suite 4000
                                    Los Angeles, California  90071-2007
                                    Attention: W. Alex Voxman, Esq.

               or to such other address as any party may have furnished to the
others in writing in accordance herewith, except that notices of change of
address shall be effective only upon receipt.

               (g)  Headings.  Section headings in this Agreement are included
                    --------
herein for convenience of reference only and shall not constitute a part of this
Agreement for any other purpose.

               (h)  Waiver.  Failure to insist upon strict compliance with any
                    ------
of the terms, covenants, or conditions hereof shall not be deemed a waiver of
such term, covenant, or condition, nor shall any waiver or relinquishment of, or
failure to insist upon strict compliance with, any right or power hereunder at
any one or more times be deemed a waiver or relinquishment of such right or
power at any other time or times.

               (i)  Employee's Acknowledgment.  Employee acknowledges (i) that
                    -------------------------
he has consulted with or has had the opportunity to consult with independent
counsel of his own choice concerning this Agreement and has been advised to do
so by the Company, and (ii) that he has read and understands the Agreement, is
fully aware of its legal effect, and has entered into it freely based on his own
judgment.

                                       11
<PAGE>

               (j)  Counterparts.  This Agreement may be executed in several
                    ------------
counterparts, each of which shall be deemed to be an original but all of which
together will constitute one and the same instrument.

               (k)  Entire Agreement; Amendment.  This Agreement (i) contains a
                    ---------------------------
complete statement of all the arrangements between the parties with respect to
Employee's employment by the Company, (ii) supersedes all prior and existing
negotiations and agreements between the parties concerning Employee's employment
and (iii) can only be changed or modified pursuant to a written instrument duly
executed by each of the parties hereto.

               (l)  Expenses.  Each party to this Agreement shall bear its
                    --------
respective expenses incurred in connection with the preparation, negotiation,
execution and performance of this Agreement; provided that, the Company shall
pay up to $10,000 of the reasonable fees and expenses of counsel to Employee
incurred with respect to this Agreement.

                            (Signature Page Follows)

                                       12
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

                                 DR.KOOP.COM, INC.



                                 By: /s/ Richard Rosenblatt
                                    ------------------------------------
                                    Name:
                                    Title:

                                 EMPLOYEE


                                 /s/ William H. Carlson
                                 ---------------------------------------
                                 William H. Carlson

                                      S-1