EXHIBIT 99.1

                    CERTIFICATION BY CHIEF EXECUTIVE OFFICER

In connection with the periodic report of Connetics Corporation (the "Company")
on Form 10-K for the period ended December 31, 2002, as filed with the
Securities and Exchange Commission (the "Report"), I, Thomas G. Wiggans,
President and Chief Executive 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:  March 5, 2003



       /s/ Thomas G. Wiggans
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Thomas G. Wiggans
President and Chief Executive Officer