AIMS: To identify factors associated with the use of single or dual antiplatelet therapy in patients prescribed warfarin following coronary stenting and to investigate whether single (aspirin or thienopyridine) vs. dual antiplatelet therapy plus warfarin leads to an excess of adverse outcomes. METHODS AND RESULTS: We analysed data from 800 patients with an acute coronary syndrome who underwent coronary stenting (130 patients received a drug-eluting stent) and were discharged on warfarin and either dual (n = 580) or single (n = 220) antiplatelet therapy. The use of single antiplatelet therapy was more common in Europe than in the USA (34 vs. 17%, P <>