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                                                                   EXHIBIT 10.40

CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTIONS.

                   SECOND AMENDMENT TO COLLABORATION AGREEMENT

         This Amendment (the "Amendment") to that certain Collaboration
Agreement (the "Agreement") entered into as of the 30th day of March, 1999, by
and between WebMD, Inc., a Georgia corporation ("Company"), and E.I. du Pont de
Nemours and Company, a Delaware corporation ("DuPont") is made on the 28th day
of May, 1999.

                                    RECITALS

         1.       DuPont and WebMD are parties to the Agreement;

         2.       DuPont and WebMD have agreed upon certain additional terms
with regard to the division of certain revenues according to the terms of the
Agreement; and

         3.       DuPont and WebMD desire to enter into this Amendment to
provide for such additional terms.

                               TERMS OF AMENDMENT

         1.       Schedule 1 of the Agreement is hereby deleted and replaced in
its entirety by the Schedule 1 attached hereto.

         IN WITNESS WHEREOF, DuPont and WebMD have executed this Amendment
effective as of the date hereof.

                                    E.I. du Pont de Nemours and Company


                                    By:  /s/
                                          -------------------------------------
                                    Its:
                                          -------------------------------------


                                    WebMD, Inc.


                                    By:  /s/
                                          -------------------------------------

                                    Its:
                                          -------------------------------------





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                                   Schedule 1

                           DuPont's Share of Revenues

<TABLE>
<CAPTION>
                                                    CONSUMER                      PROFESSIONAL
                                                    --------                      ------------
<S>  <C>                                        <C>                              <C>
1.   Advertising/Sponsorship                          [*]%                       [*]% until DuPont recovers
                                                                                 its out of pocket
                                                                                 subscription fees less
                                                                                 payments from Life Science
                                                                                 partners; [*]% thereafter

2.  Carriage Fees                                     [*]%                       [*]% Lounge and Library only

3.  Upsales on Services                               N/A                        [*]% on net revenue

4.  e-Commerce

    a.  bought through WebMD                    [*]% of net proceeds             [*]% of net proceeds

    b.  bought through DuPont                   [*]% of net proceeds             [*]% of net proceeds

    c.  E*Trade payments to WebMD               [*]% of net revenue              [*]% of net proceeds
        based on commissions on
        deposit accounts and
        securities trading
        commissions (the carriage
        fees element of the E*Trade
        relationship are covered in
        #2 above)
</TABLE>

Notes

1.       Revenue splits of advertising/sponsorship receipts shall be net of all
         direct third party vendor costs (e.g., DoubleClick commissions).

2.       Revenues derived from portal agreements (e.g., CNN, Lycos, MSN) are
         applied [*]% to DuPont and [*]% to WebMD for the carriage fees paid
         until WebMD recovers the portal fees paid, and are then applied as
         shown above.

3.       Revenue splits of e-commerce receipts shall be net of discounts, bad
         debts, returns and direct costs such as advertising, sales, product
         costs, distribution and other costs.


[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED
WITH RESPECT TO THE OMITTED PORTIONS.


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4.       Consumer split is for 3 years on e-commerce, and non-pharmaceutical
         advertising, sponsorship and carriage, and 5 years on pharmaceutical
         advertising, sponsorship and carriage; professional split is for 5
         years except as otherwise noted in Section 4.5 of this Agreement.

5.       WebMD and DuPont will negotiate in good faith for amendments to the
         professional revenue split described above to accommodate proposals by
         third parties to sponsor additional physician subscribers to WebMD.

6.       DuPont's portion of the revenue derived from the professional site
         shall be one-half of the percentages stated in the "Professional"
         column of this Schedule 1 pertaining to or derived from the physicians
         subscribers to the WebMD service to be sponsored by DuPont under this
         Agreement and/or the physician subscribers to the WebMD service to be
         sponsored by Microsoft Corporation under that certain Microsoft
         Collaboration and Cross-Promotion Agreement between Microsoft
         Corporation and WebMD, Inc., dated May 6, 1999.

7.       DuPont's right to the revenue derived from Advertising/Sponsorship on
         the professional site shall begin on the day it begins sponsorship of
         physician subscribers to the WebMD service other than those subscribers
         referred to on Schedule 2 of this Agreement.


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