Pharmacologic advances in the use of antithrombotic agents have paralleled the technologic innovations used in patients undergoing coronary interventions. The recognition of the central role of platelets in the development of complications related to coronary interventions led to the investigation and subsequent routine use of several antiplatelet agents as adjuvants to coronary intervention. Thus, the oral agents aspirin and either ticlopidine or clopidogrel are routinely administered after coronary stenting. Intravenous glycoprotein (GP) IIb/IIIa antagonists have been extensively studied and reduce adverse cardiac events in patients undergoing coronary interventions, especially those receiving intracoronary stents. Despite the growing use of GP IIb/IIIa antagonists, much information remains unknown as to the proper dosing and the effects these agents have on other elements of the hemostatic and vascular systems.