Clopidogrel summary

Feature	Recommendations, Effect
Dosing	Loading dose 300–900 mg, maintenance dose 75 mg daily
Time to onset	5–6 Hours to reach maximal platelet inhibition but increasing doses achieve the same level of platelet inhibition more rapidly
Metabolism	Converted to active form in the liver by the CYP450 system, most particularly enzymes 1A2, 2C19, and 3A4
Action	Irreversibly disables P2Y12 platelet receptor, preventing ADP-induced downstream conformational change of the GPIIb/IIIa receptor that is required for platelet activation
Interactions that increase potency	Cigarette smoke (controversial)
Interactions that decrease potency	PPIs (controversial)
Side effects	Hemorrhage, rash, pruritus, TTP
Cost	US $103/month (2007)

Note:—TTP indicates thrombotic thrombocytopenic purpura.