Antiplatelet drugs for stroke prevention.

Antiplatelet (AP) drugs play a major role in stroke prevention. Aspirin (50 -1300 mg), ticlopidine (500 mg), clopidogrel (75 mg) and dipyridamole (400 mg) are effective in secondary prevention of atherothrombotic brain infarct s. Aspirin has been the most extensively studied drug and remains the most cost-effective one. The optimal dose is still debated; doses between 100 an d 300 mg are the most widely used. The preventive efficacy of aspirin is al ready present at the acute phase of cerebral infarct. In primary prevention, aspirin nearly halves the risk of myocardial infarct ion but does not reduce that of stroke. Cardiac diseases with a high embolic risk require the use of oral anticoagu lation. In non valvular atrial fibrillation, the choice of antithrombotic d rugs depends on risk stratification: oral anticoagulants are indicated in h igh risk subjects whereas aspirin is recommended in low risk subjects and w hen oral anticoagulants are contraindicated. Studies with new associations of AP and with new drugs are required to incr ease the yield of the antiplatelet approach in high risk subjects, this sho uld be done in parallel with efforts to detect and to treat the vascular ri sk factors associated with the development of a mass approach for stroke pr imary prevention.