VitalsCentral

Clopidogrel

Plavix

FDA ApprovedCardiovascular AgentsAntiplatelets
Half-life: Active metabolite about 30 minutes; parent about 6 hoursPregnancy: Category B

Overview

Clopidogrel is a thienopyridine antiplatelet agent used to reduce atherothrombotic events in patients with acute coronary syndrome, recent myocardial infarction or stroke, and peripheral arterial disease.

Indications

  • Acute coronary syndrome
  • Recent myocardial infarction
  • Recent ischemic stroke
  • Peripheral arterial disease

Contraindications

  • Active pathological bleeding
  • Hypersensitivity to clopidogrel

Classification

Cardiovascular AgentsAntiplateletsCardiovascular System

Mechanism of Action

A prodrug whose active metabolite irreversibly inhibits the platelet P2Y12 ADP receptor, preventing ADP-mediated activation of the glycoprotein IIb/IIIa complex and platelet aggregation.

Pharmacodynamics

Produces dose-dependent, irreversible inhibition of platelet aggregation for the lifespan of the platelet (7-10 days). Requires CYP-mediated activation, notably CYP2C19.

Pharmacokinetics

Absorption
Rapidly absorbed; at least 50% absorbed orally.
Distribution
Clopidogrel and its main circulating metabolite are highly protein bound.
Metabolism
Extensively metabolized; a minor fraction is activated via CYP2C19 and other CYP enzymes to the active thiol metabolite.
Excretion
Excreted roughly equally in urine and feces.
Half-life
Active metabolite about 30 minutes; parent about 6 hours
Bioavailability
At least 50%
Protein Binding
Approximately 98%

Dosage

Typical dosage: 75 mg once daily, often with a 300-600 mg loading dose

Available Forms

  • Tablet

Side Effects

Common

  • Bruising
  • Bleeding
  • Diarrhea
  • Rash

Serious

  • Major hemorrhage
  • Gastrointestinal bleeding

Rare

  • Thrombotic thrombocytopenic purpura

Drug Interactions

Omeprazolemoderate

Strong CYP2C19 inhibition reduces conversion to the active metabolite and may lessen antiplatelet effect.

Warfarinmajor

Combined use substantially increases the risk of bleeding.

Warnings

⚠️BLACK BOX WARNING

Clopidogrel effectiveness depends on conversion to its active metabolite by CYP2C19. Poor metabolizers have reduced antiplatelet response and higher rates of cardiovascular events; consider alternative therapy or genotype-guided dosing.

Pregnancy

Category B

Toxicity

Overdose prolongs bleeding time and increases bleeding risk.

Overdose

No specific antidote. Platelet transfusion may be used to restore hemostasis in serious bleeding.

References

Looking for patient-friendly information? Visit RemedyDoor for easy-to-read guides about this medication.