Drug information of Clopidogrel

Clopidogrel

Drug group:

Clopidogrel keeps the platelets in your blood from coagulating (clotting) to prevent unwanted blood clots that can occur with certain heart or blood vessel conditions. Clopidogrel is used to prevent blood clots after a recent heart attack or stroke, and in people with certain disorders of the heart or blood vessels.

Mechanism of effect

Clopidogrel is a thienopyridine derivative, chemically related to ticlopidine, which inhibits platelet aggregation. It acts by irreversibly modifying the platelet adenosine diphosphate (ADP) receptor. Therefore, platelet aggregation is inhibited for both ADP-mediated and ADP-amplified (by other agonists) platelet activation. Consequently, platelets exposed to clopidogrel are affected for the remainder of their lifespan

Pharmacodynamic

Since clopidogrel is a prodrug, it must be metabolized by CYP450 enzymes to produce the active metabolite that inhibits platelet aggregation. This active metabolite selectively inhibits adenosine diphosphate (ADP) binding to its platelet P2Y12 receptor and subsequently the ADP-mediated activation of the glycoprotein GPIIb/IIIa complex, thereby inhibiting platelet aggregation

Pharmacokinetics

Rapidly absorbed. T max is approximately 1 h. C max is approximately 3 mg/L 98% reversibly bound to plasma proteins; active metabolite is 94% reversibly bound to plasma proteins Extensively metabolized in the liver; undergoes rapid hydrolysis to carboxylic acid derivative (active). 50% excreted in urine; 46% excreted in feces. The half-life of the active metabolite is 8 h Onset:2 h. Peak:3 to 7 days. Duration:Approximately 5 days.

Dosage

Acute Coronary Syndrome (ST-Segment Elevation Acute MI) Adults PO 75 mg once daily in combination with aspirin, with or without thrombolytic agents. Treatment may be initiated with or without a loading dose. Recent MI, Recent Stroke, or Established Peripheral Arterial Disease Adults PO 75 mg once daily

Alerts

1-The effectiveness of clopidogrel is dependent on its activation to an active metabolite, principally by CYP2C19. Clopidogrel at recommended doses forms less of that metabolite and has a smaller effect on platelet function in patients who are CYP2C19 poor metabolizers. Poor metabolizers with ACS or undergoing percutaneous coronary intervention treated with clopidogrel at recommended doses exhibit higher CV event rates than patients with normal CYP2C19 function. 2-Monitor patient for bleeding or unusual bruising

Points of recommendation

• Advise patient that each dose may be taken without regard to meals, but to take with food if stomach upset occurs. • Advise patient that if a dose is missed, to skip that dose and take the next dose at the regularly scheduled time. • Instruct patient not to change the dose or stop taking unless advised by health care provider. • Inform patient that it may take longer than usual to stop bleeding while taking clopidogrel and to report bleeding or unusual bruising to health care provider immediately. • Advise patient to inform health care providers about use of this drug before undergoing surgical or dental procedures, and before any new drug is taken

Pregnancy level

B

Related drugs

Prasugrel , Ticlopidine , Ticagrelor


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