No circadian effect on nortriptyline kinetics in man

Abstract

Kinetics of a single 100‐mg dose of nortriptyline were studied in 10 normal men who took this dose at 9 a.m. in the morning and on another occasion at 9 p.m. Only minimal differences in kinetic parameters were observed, none enough to be of any clinical consequence. A rather high first‐pass metabolism of the drug was evident by high plasma concentrations of 10‐hydroxynortriptyline. it is thus unlikely that the recent custom of giving single daily doses of tricyclic antidepressants in the evening excludes regimens with more favorable drug kinetics.