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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the references to our firm under the captions "Selected Financial
Data" and "Experts" and to the use of our report dated May 29, 2000, except for
the last paragraph of Note 10, as to which the date is July 25, 2000, in
Amendment No. 3 to the Registration Statement (Form S-1) and related prospectus
of Arena Pharmaceuticals, Inc. for the registration of shares of its common
stock.
/s/ ERNST & YOUNG LLP
July 25, 2000
