Exhibit 32.1 CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350 AS ADOPTED PURSUANT TO SECTION 906 OF THOE SARBANES-OXLEY ACT OF 2002 Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, with respect to the Quarterly Report of the Company on Form 10-Q for the quarter ended September 30, 2004, (the "Report"), each of the undersigned officers of Impax Laboratories, Inc. does hereby certify that: 1. The Report fully complies with the requirements of the 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. /s/ Barry R. Edwards Chief Executive Officer Date: November 15, 2004 - ------------------------ Barry R. Edwards /s/ Cornel C. Spiegler Chief Financial Officer Date: November 15, 2004 - ------------------------ Cornel C. Spiegler The foregoing certification is being furnished solely pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (Section 1350 of Chapter 63 of Title 18 of the U.S. Code) and is not being filed as part of the Report or as a separate disclosure document.