<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>5
<FILENAME>c75799exv99w1.txt
<DESCRIPTION>CERTIFICATION OF PRESIDENT/CHIEF EXECUTIVE OFFICER
<TEXT>
<PAGE>

                                                                    EXHIBIT 99.1

                   CERTIFICATION PURSUANT TO 18 U.S.C. (S)1350

       (ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002)

         In connection with the periodic report of Sheffield Pharmaceuticals,
Inc. (the "Company") on Form 10-K for the period ended December 31, 2002 dated
April 15, 2003, filed with the Securities and Exchange Commission (the
"Report"), I, Thomas M. Fitzgerald, President, Chief Executive Officer and
Acting Chief Financial Officer of the Company, hereby certify as of the date
hereof, solely for purposes of Title 18, Chapter 63, Section 1350 of the United
States Code, that to the best of my knowledge:

         (1) the Report fully complies with the requirements of Section 13(a) or
             15(d), as applicable, of the Securities Exchange Act of 1934, and

         (2) the information contained in the Report fairly presents, in all
             material respects, the financial condition and results of
             operations of the Company at the dates and for the periods
             indicated.

Date: April 15, 2003                       /s/ Thomas M. Fitzgerald
                                           ----------------------------------
                                           President and Chief Executive Officer
                                           And Acting Chief Financial Officer

A signed original of this written statement required by Section 906 has been
provided to Sheffield Pharmaceuticals, Inc. and will be retained by Sheffield
Pharmaceuticals, Inc. and furnished to the Securities and Exchange Commission or
its staff upon request.

                                       56

</TEXT>
</DOCUMENT>
