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Exhibit 32.1

STATEMENT PURSUANT TO 18 U.S.C. §1350

        Pursuant to 18 U.S.C. §1350, the undersigned certifies that this Annual Report on Form 10-K of Pacira Pharmaceuticals, Inc. for the year ended December 31, 2012, fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that the information contained in this report fairly presents, in all material respects, the financial condition and results of operations of Pacira Pharmaceuticals, Inc.

Date: March 7, 2013 /s/ DAVID STACK
David Stack
President and Chief Executive Officer
(Principal Executive Officer)

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Exhibit 32.1

STATEMENT PURSUANT TO 18 U.S.C. §1350