This patient who is receiving thrombolytic therapy for an ST-elevation myocardial infarction (STEMI) should be given clopidogrel, 300 mg orally. Clopidogrel is the most widely studied antiplatelet agent in patients undergoing reperfusion for STEMI. Clopidogrel is associated with improved outcomes and no apparent increase in the risk of bleeding when used with concomitant thrombolytic therapy and with primary percutaneous coronary intervention (PCI). In the CLARITY-TIMI 28 study examining clopidogrel as adjunctive therapy in patients undergoing thrombolysis, there was a 6.7% absolute risk reduction in the incidence of occluded infarct-related artery or recurrent myocardial infarction or death in patients assigned to clopidogrel when compared with placebo.

Abciximab is a platelet glycoprotein IIb/IIIa inhibitor that further inhibits platelet aggregation and impairs platelet activation. Glycoprotein IIb/IIIa inhibitors are used in patients undergoing PCI. Owing to the risk of increased bleeding with these agents, their use should be reserved for administration during PCI, rather than “up front” in the emergency department. Large studies have shown no clear mortality benefit and significantly higher rates of major bleeding in patients undergoing fibrinolysis treated with abciximab versus placebo. Use of platelet glycoprotein IIb/IIIa inhibitors in patients undergoing thrombolysis is not currently recommended.

For STEMI patients undergoing primary PCI, both prasugrel and ticagrelor have shown superior efficacy compared with clopidogrel. However, use of these agents in patients treated with thrombolytic therapy has not been well studied, and little evidence exists to recommend the use of either of these agents in patients receiving thrombolytic therapy.