Imipramine pamoate suspension was administered orally to 57 healthy children in a double-blind crossover design study with dosage sequence randomized to determine whether 10 or 25 mg daily would be more effective in controlling nocturnal enuresis, when compared to treatment with a placebo. Both dosage levels of imipramine produced a statistically significant decrease in the number of wet nights when compared to placebo therapy (P<0.01). After the double-blind trial, imipramine treatment was continued in 18 patients at several dosage levels for three months. After discontinuing therapy, there was significantly fewer wet nights than during the final period of drug treatment. Complete monitoring of several laboratory determinations revealed no significant abnormalities at dosages employed. A unified concept concerning the action of imipramine in enuresis, with emphasis on micturition, maturation of neural pathways, and the level of sleep is discussed.Si nce the first observation by MacLean1 on the application of imipramine hydrochloride (Tofranil) in the management of enuresis, over 100 investigations have appeared on the subject. Statistical evaluation of well controlled investigations show that imipramine is superior to pla¬ cebo in decreasing wetting frequen¬ cy. Uncertainty still exists con¬ cerning the drug's proper dosage, length of administration, and meth¬ od of drug withdrawal. Accordingly, imipramine in the pa¬ moate suspension was administered to 57 healthy children in a doubleblind controlled trial to determine the appropriate dosage level in con¬ trolling nocturnal enuresis. In the second part of the investigation, the continuing effect of the pamoate sus¬ pension in various dosage levels was