A controlled double blind comparative study of single dose administration of imipramine pamoate and divided dose of imipramine hydrochloride in depressive illness.

A double blind therapeutic comparison of single dose administration of imipramine pamoate and divided dose of imipramine hydrochloride was made in 40 indoor patients suffering from depressive illness. A fixed dose of 150 mg was used for both drugs for four weeks, employing randomized methodology with placebo capsules and tablets to balance dosage schedules. Four patients two from each group were dropped, leaving 36 patients for final analysis. The criteria of assessment were Hamilton Rating Scale and global evaluation by both the psychiatrist and the patients. Both the dosage forms were found to be highly effective as anti-depressants. Imipramine pamoate seemed to provide more consistent improvement but statistically the differences were not significant at the end of four weeks treatment. The major conclusion drawn from the study was the confirmation of therapeutic equivalence between a single daily dose of 150 mg of imipramine pamoate and divided dose of 150 mg of imipramine hydrochloride. Generally mild side-effects occurred with equal frequency in both the groups and no adverse effects on haemopoietic, renal or hepatic function were seen with either dosage form.