Last reviewed 2026-04-22 · How we verify

clopidogrel (SR25990C)

Clopidogrel is a thienopyridine antiplatelet agent that irreversibly inhibits ADP-induced platelet aggregation by blocking the P2Y12 adenosine diphosphate receptor on platelets.

Clopidogrel is a thienopyridine antiplatelet agent that irreversibly inhibits ADP-induced platelet aggregation by blocking the P2Y12 adenosine diphosphate receptor on platelets. Used for Acute coronary syndrome (unstable angina and non-ST-elevation myocardial infarction), ST-elevation myocardial infarction, Peripheral arterial disease.

At a glance

Mechanism of action

Clopidogrel is a prodrug that requires hepatic metabolism to form its active metabolite, which then binds irreversibly to the P2Y12 receptor on platelet surfaces. This prevents ADP-mediated platelet activation and aggregation, reducing thrombotic events. The antiplatelet effect is cumulative and reaches steady state after 3–7 days of daily dosing.

Approved indications

• Acute coronary syndrome (unstable angina and non-ST-elevation myocardial infarction)
• ST-elevation myocardial infarction
• Peripheral arterial disease
• Ischemic stroke or transient ischemic attack
• Secondary prevention of atherothrombotic events

Common side effects

• Bleeding (major and minor)
• Dyspepsia
• Rash
• Diarrhea
• Thrombotic thrombocytopenic purpura (TTP)

Key clinical trials

• Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE A) (PHASE3)
• Safety and Efficacy of Clopidogrel for Cerebral Infarction Treatment (PHASE4)
• Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE W) (PHASE3)
• Efficacy and Safety in Patients With Acute Coronary Syndrome Without ST-Segment Elevation (PHASE3)

Primary sources

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