Antiplatelet therapy in stroke prevention: present and future.

White platelet-fibrin thrombi often form on roughened endothelial surfaces and unstable arterial plaques. Agents that reduce the tendency of platelets to aggregate, agglutinate, and secrete and to attach to endothelial surfaces have been explored as agents that prevent brain and heart infarction. Aspirin, ticlopidine, clopidogrel, dipyridamole, cilostazol, and glycoprotein llb/llla inhibitors are all used now and have various different modes of action and functions.