Evening intake of aspirin is associated with a more stable 24-h platelet inhibition compared to morning intake: a study in chronic aspirin users.

Daily generation of novel platelets may compromise aspirin's platelet inhibitory action, especially near the end of the regular 24-h dosing interval. A contributor to this attenuation could be the endogenous circadian rhythm. The primary objective of this study was to assess platelet activity 12 and 24 h after different times of aspirin intake (c.