Exhibit 31.1


                           CERTIFICATION OF DISCLOSURE
                             AS ADOPTED PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

          I, Robert Essner, certify that:

               1.   I have reviewed this Quarterly Report on Form 10-Q of Wyeth;

               2.   Based on my knowledge, this report does not contain any
                    untrue statement of a material fact or omit to state a
                    material fact necessary to make the statements made, in
                    light of the circumstances under which such statements were
                    made, not misleading with respect to the period covered by
                    this report;

               3.   Based on my knowledge, the financial statements, and other
                    financial information included in this report, fairly
                    present in all material respects the financial condition,
                    results of operations and cash flows of the registrant as
                    of, and for, the periods presented in this report;

               4.   The registrant's other certifying officer(s) and I are
                    responsible for establishing and maintaining disclosure
                    controls and procedures (as defined in Exchange Act Rules
                    13a-15(e) and 15d-15(e)) for the registrant and have:

                    (a)  Designed such disclosure controls and procedures, or
                         caused such disclosure controls and procedures to be
                         designed under our supervision, to ensure that material
                         information relating to the registrant, including its
                         consolidated subsidiaries, is made known to us by
                         others within those entities, particularly during the
                         period in which this report is being prepared;

                    (b)  Evaluated the effectiveness of the registrant's
                         disclosure controls and procedures and presented in
                         this report our conclusions about the effectiveness of
                         the disclosure controls and procedures, as of the end
                         of the period covered by this report based on such
                         evaluation; and

                    (c)  Disclosed in this report any change in the registrant's
                         internal control over financial reporting that occurred
                         during the registrant's most recent fiscal quarter (the
                         registrant's fourth fiscal quarter in the case of an
                         annual report) that has materially affected, or is
                         reasonably likely to materially affect, the
                         registrant's internal control over financial reporting;
                         and

               5.   The registrant's other certifying officer(s) and I have
                    disclosed, based on our most recent evaluation of internal
                    control over financial reporting, to the registrant's
                    auditors and the audit committee of the registrant's board
                    of directors (or persons performing the equivalent
                    functions):


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                    (a)  All significant deficiencies and material weaknesses in
                         the design or operation of internal control over
                         financial reporting which are reasonably likely to
                         adversely affect the registrant's ability to record,
                         process, summarize and report financial information;
                         and

                    (b)  Any fraud, whether or not material, that involves
                         management or other employees who have a significant
                         role in the registrant's internal control over
                         financial reporting.



          Dated: August 8, 2003

                                By /s/            Robert Essner
                                   ---------------------------------------------
                                                  Robert Essner
                                 Chairman, President and Chief Executive Officer