Chronopharmacokinetics of ethanol. III. Variation in rate of ethanolemia decay in human subjects.

Five male human subjects were administered repeated oral doses of ethanol approximately four hours apart and were examined for venous ethanol levels during the third and fourth hours after each dose. Estimates of the slopes of the apparently linear ethanol disappearance curves exhibited statistically significant variation along a 24-hour time scale within 4 of the 5 subjects, as well as among individuals. Prior findings on one of the subjects were confirmed. It is proposed in general that pharmacokinetic parameters may vary in accord with the physiologic circadian phase at the time of drug challenge.