EXHIBIT 23.1 CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS We consent to the reference to our firm under the caption "Experts" in the Registration Statement (Form S-3) and related Prospectus of Sonus Pharmaceuticals, Inc. for the registration of 2,900,000 shares of its common stock and to the incorporation by reference therein of our report dated January 20, 2004, with respect to the financial statements of Sonus Pharmaceuticals, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2003, filed with the Securities and Exchange Commission. ERNST & YOUNG /s/ Ernst & Young Seattle, Washington May 21, 2004