Plasma aspirin levels and platelet antiaggregatory effect in oral administration

Abstract

It is known that aspirin acts as one of platelet antiaggregatory agents and also inhibits production of prostacyclin which has antiagrregatory effect. Thus administration of small dose of aspirin is recommended. In this point of view, we determined plasma aspirin levels and platelet antiaggregatory effects after administration of small dose of aspirin. Our experimentation includes eight old persons. Aggregation of plateletes was evaluated by Born's method and plasma aspirin and salicylate levels by high pressure liquid chromatography. In five cases with maximum level of aspirin above 1.30μg/ml, excellent antiaggregatory effect was seen. But in three cases, maximum aspirin levels less than 1.01μg/ml revealed no effect. According to our data, it is suggested that a fixed aspirin plasma level is necessary for platelet antiaggregatory effect, but minimum dose for oral administration differs person to person.