Concentrations of imipramine and its metabolites during enuresis therapy

Plasma concentrations of imipramine and three of its metabolites were determined in children 6 to 15 years of age who received imipramine for treatment of nocturnal enuresis. In 14 patients with reliable data the reduction in wet nights after beginning drug therapy had no apparent relationship to either imipramine concentration alone or imipramine combined with its metabolites. This finding may be related to the relatively low drug concentrations in this group of patients, a high placebo response rate, or noncompliance with the prescribed dosage regimen. Determining plasma imipramine concentrations during treatment for enuresis has questionable value as an aid to improve clinical response. This practice may occasionally be justified when avoidance of toxicity is a major concern.