EXHIBIT 99.2

                  CERTIFICATION BY THE CHIEF FINANCIAL OFFICER
                 PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED
            PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2003

                                  CERTIFICATION

In connection with the Annual Report of Merck & Co., Inc. (the "Company")
Employee Savings and Security Plan (the "Plan") on Form 11-K for the period
ended December 31, 2002 as filed with the Securities and Exchange Commission on
the date hereof (the "Report"), I, Caroline Dorsa, Vice President and Treasurer
of the Company, certify pursuant to 18 U.S.C. Section 1350, as adopted pursuant
to Section 906 of the Sarbanes-Oxley Act of 2002, that the Report fully complies
with the requirements of Section 13(a) or 15(d), as applicable, of the
Securities Exchange Act of 1934 and that the information contained in the Report
fairly presents, in all material respects, the financial condition and results
of operations of the Plan.

Dated: June 27, 2003                               /s/ Caroline Dorsa
                                                   -----------------------------
                                            Name:  Caroline Dorsa
                                            Title: Vice President and Treasurer

The foregoing certification is being furnished solely pursuant to 18 U.S.C.
Section 1350 and is not being filed as part of the Report or as a separate
disclosure document. A signed original of this written statement required by
Section 906 has been provided to Merck & Co., Inc. and will be retained by Merck
& Co., Inc. and furnished to the Securities and Exchange Commission or its staff
upon request.

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