[The use of acetylsalicylic acid as a platelet antiaggregant]. / Uso do acido acetil salicílico como antiagregante plaquetário.

PURPOSE: To comprove the efficiency of acetyl salicylic acid (ASA) as platelet antiaggregant drug, a 100 mg/day dose base. METHODS: Two hundred and fifty-eight patients were studied between 1988 and 1990. Platelet functions were measured using an aggregometer plus ADP 5 as platelet aggregation inductor. RESULTS: Two groups were studied: 1st group, using ASA (111 patients), 91 hypoaggregants; 2nd group, not using ASA (147 patients), 120 normals, 12 hypoaggregants and 15 hyperaggregants. From the 2nd group, 91 had another evaluation under the use of ASA and showed a clear effect of the drug. CONCLUSION: The use of aspirin, 100 mg/day dose, is enough to reduce platelet antiaggregation.