Exhibit 23.1 CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS We consent to the incorporation by reference in the Registration Statements (Form S-3 No. 333-73216) and (Form S-8 Nos. 333-101756, 333-92328, 333-65198, 333-57096, 333-44012, 333-87127, 333-57875) of our report dated January 24, 2003, with respect to the financial statements of Neurocrine Biosciences, Inc. included in the Annual Report (Form 10-K) for the year ended December 31, 2002. /s/ Ernst & Young LLP San Diego, California March 4, 2003