UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  FORM 10-KSB/A

               [X] ANNUAL REPORT UNDER SECTION 13 OR 15(d) OF THE
               SECURITIES AND EXCHANGE ACT OF 1934 [Fee Required]

For the fiscal year ended DECEMBER 31, 1998    Commission File Number: 000-23413

                          MEDICAL SCIENCE SYSTEMS, INC.
                 (Name of Small Business Issuer in its Charter)

                  TEXAS                             94-3123681
     (State or other jurisdiction of            (I.R.S. Employer
     incorporation or organization)            Identification No.)

                          100 N.E. LOOP 410, SUITE 820
                            SAN ANTONIO, TEXAS 78216
               (Address of principal executive offices)(Zip Code)

                    Issuer's Telephone Number: (210) 349-6400

         Securities registered under Section 12(b) of the Exchange Act:

    (Title of each class)            (Name of each exchange on which registered)
 COMMON STOCK, NO PAR VALUE                    BOSTON STOCK EXCHANGE

         Securities registered under Section 12(g) of the Exchange Act:

                              (Title of each class)
                           COMMON STOCK, NO PAR VALUE

Check whether the issuer (1) filed all reports required to be filed by Section
13 or 15(d) of the Exchange Act during the past 12 months (or for such shorter
period that the Registrant was required to file such reports), and (2) has been
subject to such filing requirements for the past 90 days. YES (X)   NO ( )

Check if there is no disclosure of delinquent filers in response to Item 405 of
Regulation S-B is not contained in this form, and no disclosure will be
contained, to the best of registrant's knowledge, in definitive proxy or
information statements incorporated by reference in Part III of this Form 10-KSB
or any amendment to this Form 10-KSB. ( )

State issuer's revenues for its most recent fiscal year:  $412,942.

As of March 23, 1999, the aggregate value of the Registrant's Common Stock held
by non-affiliates, based upon the average bid and asked price as of such date,
was $2,649,732.

State the number of shares outstanding of each of the issuer's classes of common
equity, as of the latest practicable date: There were 5,548,470 shares of the
Registrant's Common Stock issued and outstanding as of March 23, 1999.

                                     PART II

ITEM 5.    MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER
           MATTERS

MARKET INFORMATION

      The Company's Common Stock began trading on The Nasdaq SmallCap Market on
November 26, 1997 under the symbol "MSSI" and on the Boston Stock Exchange under
the symbol "MSC." Prior to that date, there was no established trading market
for the Common Stock. the following table sets forth, for the periods indicated,
the high and low bid prices for the Common Stock, as reported by the Nasdaq
Small Cap market, since the Common Stock commenced public trading. The
quotations represent prices in the over-the-counter market between dealers and
securities, and do not include retail markup, markdown or commissions and may
not necessarily represent actual transactions.


1998:                                             HIGH        LOW
                                                  ----        ---
First Quarter..........................          $6.063      $2.938
Second Quarter ........................          $5.00       $3.50
Third Quarter..........................          $4.25       $1.313
Fourth Quarter.........................          $2.125      $0.469

1997:
November 26 - December 31, 1997........          $9.00       $3.875


NUMBER OF SHAREHOLDERS

      As of March 23, 1999, there were approximately 475 beneficial holders and
97 record holders of the Company's Common Stock.

DIVIDENDS

      The Company has not declared any dividends to date and does not plan to
declare any dividends in the foreseeable future.


USE OF PROCEEDS FROM SALES OF REGISTERED SECURITIES

      On November 26, 1997, the Company completed an initial public offering of
its Common Stock, no par value (the "Offering"). Aggregate proceeds from the
Offering were $16,200,000, and the net proceeds were $14,904,000. Of the net
proceeds, $1,815,042 has been used to repay debt, $2,836,018 has been used for
research and development expenses, $4,291,384 has been used for marketing and
sales expenses, $3,652,771has been used for general and administrative expenses,
$200,900 has been paid to Michael G. Newman, a director and former employee of
the

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Company, pursuant to a severance agreement, and the remaining $2,308,785 has
been allocated to general working capital requirements.

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                                   SIGNATURES

      In accordance with Section 13 or 15(d) of the Exchange Act, the registrant
caused this amended report to be signed on its behalf by the undersigned,
thereunto duly authorized.

                              MEDICAL SCIENCE SYSTEMS, INC.


Date:   May 18, 1999                By: /s/ U. SPENCER ALLEN
                                    U. Spencer Allen
                                    Chief Financial Officer and Treasurer

      In accordance with the Exchange Act, this amended report has been signed
below by the following persons on behalf of the registrant and in the capacities
and on the date indicated.

   SIGNATURES                             TITLE                  DATE SIGNED

/s/ PAUL J. WHITE                President, Chief Executive
Paul J. White                    Officer and Director            May 18, 1999
                                 (PRINCIPAL EXECUTIVE OFFICER)

/s/ U. SPENCER ALLEN             Chief Financial Officer and
U. Spencer Allen                 Treasurer                       May 18, 1999
                                 (PRINCIPAL FINANCIAL AND
                                   ACCOUNTING OFFICER)

/s/ KENNETH S. KORNMAN           Chief Scientific Officer and    May 18, 1999
Kenneth S. Kornman               Director

/s/ MICHAEL G. NEWMAN            Secretary and Director          May 18, 1999
Michael G. Newman

/s/ THOMAS A. MOORE              Director                        May 18, 1999
Thomas A. Moore

/s/ RONALD A. LAROSA             Director                        May 18, 1999
Ronald A. LaRosa

/s/ PHILIP R. REILLY
Philip R. Reilly                 Director                        May 18, 1999

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