Platelet Inhibition by Single Low-Dose Aspirin, Using the Newly Developed Aggregometry with the Laser Light Scattering Method.

Low-dose aspirin (acetylsalicylic acid 81 mg/day, LDA) is often used as an antiplatelet drug in the treatment of cardiovascular and cerebrovascular diseases as well as for patients with anti-phospholipid antibody syndrome. In this study, we explored the duration of the inhibitory effect of a single LDA on platelet aggregation, using the newly developed aggregometry with the laser light scattering method. Five healthy volunteers (females between 23 and 30 years old) ingested 81 mg of buffered aspirin. Platelet aggregation was measured with adenosine 5'-diphosphate before the ingestion and at the 1st, 2nd, 4th, 6th, and 8th day thereafter. The results showed that the effect of 81 mg of aspirin continues for at least 8 days, which suggested that the intermittent administration of 81 mg of aspirin (a few times a week) might be an alternative way to induce the anti-platelet effect.