What is the role for other antiplatelet drugs?
No. The mechanism of action and kinetics of platelet-active drugs has been recently reviewed.10 ASA uniquely acts to acetylate (PG)H-synthase and to irreversibly inhibit the cyclooxgenase activity in platelets and vascular endothelium. This action occurs with doses of ASA as low as 50 mg. Ticlopidine and clopidogrel are thienopyridines which act by selectively inhibiting adenosine phosphate induced platelet aggregation. Platelet function only recovers slowly upon drug withdrawal. Dipyridamole inhibits platelet cyclic nucleotide phosphodiesterase and uptake of adenosine. Which of these actions leads to the antiplatelet effect is unknown.
