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.