<Page> EXHIBIT 23.1 Consent of Independent Accountants We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated February 8, 2002 relating to the financial statements, which appears in Triangle Pharmaceuticals, Inc.'s Annual Report on Form 10-K for the year ended December 31, 2001. We also consent to the reference to us under the heading "Experts" in such Registration Statement. /s/ PRICEWATERHOUSECOOPERS LLP Raleigh, North Carolina September 20, 2002