Mechanism of Action

Clopidogrel is considered a thienopyridines and acts as a P2Y12 receptor blocker resulting in the inhibition of platelet aggregation. Clopidogrel is related to the similar agents prasugrel, ticagrelor, and ticlopidine.

Clopidogrel has delayed onset of action, no means of reversing the effects, and a significant percentage of people simply do not respond to this therapy (estimates ranging from 4-34%).


Clopidogrel is indicated in the treatment of acute coronary syndromes and in the prevention of thrombotic events.

Adverse Reactions

Bleeding, neutropenia (rare), thrombotic thrombocytopenic purpura or TTP (rare)


Platelet function assays are available to measure a patient’s response to clopidogrel therapy. The common practice is to use prasugrel or ticagrelor if the patient is found to be clopidogrel resistant.