|Composition||Clopidogrel 75mg Tablets|
|Indication||Prophylaxis of thromboembolic disorders Acute coronary syndrome|
|Mechanism of Action||
Clopidogrel selectively inhibits adenosine diphosphate (ADP) from binding to its platelet P2Y12 receptor and subsequent activation of glycoprotein GPIIb/IIIa complex thus reducing platelet aggregation.
Absorption: Rapidly but incompletely absorbed from the GI tract (approx 50%). Time to peak plasma concentration: Approx 30-60 min.
Distribution: Plasma protein binding: 98% (parent drug); 94% (carboxylic acid derivative).
Metabolism: Undergoes extensive hepatic metabolism via esterase-mediated hydrolysis to inactive carboxylic acid derivative and by CYP450-mediated (primarily CYP2C19 isoenzyme) oxidation to active thiol metabolite.
Excretion: Via urine (approx 50%); faeces (approx 46%) both as metabolites and unchanged drug.
Haematoma, epistaxis, diarrhoea, dyspepsia, abdominal pain, bruising, bleeding at puncture site. Rarely, Stevens-Johnson syndrome, erythema multiforme, serum sickness, interstitial pneumonitis, lichen planus, myalgia.
Potentially Fatal: Intracranial bleeding, GI and retroperitoneal haemorrhage, blood dyscrasias, thrombotic thrombocytopenic purpura.
Patient at risk of increased bleeding from trauma, surgery or other pathological conditions. Renal and hepatic impairment. Pregnancy and lactation. Monitoring Parameters Monitor for signs of bleeding; Hb and haematocrit periodically.
Prophylaxis of thromboembolic disorders Adult: 75 mg once daily.
Acute coronary syndrome Adult: For ST-elevation MI: In combination w/ aspirin: 75 mg once daily. Loading dose: 300 mg for patients 75 yr. Continue treatment for at least 4 wk. For unstable angina, non-ST-elevation MI: In combination w/ aspirin: Initially, 300 mg loading dose, followed by 75 mg once daily for up to 12 mth.