Clopidogrel resistance (ie, decreased inhibition of platelet function after administration of clopidogrel) may occur in 30% of patients and may relate to factors such as bioavailability, noncompliance, underdosing, lower absorption, drug interference, or single nucleotide polymorphisms.24,57,59 Poor response to oral antiplatelet agents increases the risk of thrombotic events, including myocardial infarction,60 particularly after coronary angioplasty.61 The authors of a recent meta-analysis suspect that the cause of clopidogrel resistance is an interaction with glycoprotein IIb/IIIa inhibitors and the use of different cutoffs to identify nonresponders.