Table 1:

Characteristics of clopidogrel and the new antiplatelet agents prasugrel and ticagrelor 15

Characteristic Clopidogrel Prasugrel Ticagrelor
Pharmacology Thienopyridine drug; irreversibly inhibits P2Y 12 receptor Thienopyridine drug; irreversibly inhibits P2Y 12 receptor Non-thienopyridine drug; reversibly inhibits P2Y 12 receptor
Metabolism Prodrug; requires 2-step bioactivation via cytochrome P450 3A4 and 2C19 enzymes Prodrug; requires 1-step bioactivation via cytochrome P450 2C19 enzyme Direct-acting; active moiety
Loading dose 300–600 mg 60 mg 180 mg
Maintainance dose 75 mg/d 10 mg/d (5 mg/d if age ≥ 75 yr or body weight ≤ 60 kg) 90 mg twice daily
When to stop before surgery 5–7 d 5–7 d 5 d
Avoid use in patients with:

  • History of stroke or transient ischemic attack

  • Body weight ≤ 60 kg

  • Age ≥ 75 yr