Tranylcypromine vs nortriptyline vs placebo in depressed outpatients: a controlled trial.

This study was designed to compare the therapeutic and adverse effects of tranylcypromine (a monoamine oxidase inhibitor), nortriptyline (a tricyclic antidepressant), and placebo. A total of 122 depressed outpatients randomly assigned to double-blind treatment with one of these agents completed the 4-week protocol. Treatment groups were balanced for proportions of endogenous versus nonendogenous depressions, defined according to the Research Diagnostic Criteria; however, nonendogenous depressions outnumbered endogenous depressions by such a large proportion (4:1) that meaningful statistical comparisons were limited to the nonendogenous group. In this group, both active drugs proved more effective than placebo, with little differences between the two active drugs except in the areas of side effects and of differential sensitivity of the outcome scales to a given drug. It was concluded that tranylcypromine, a drug which has received relatively little use and study in recent years, represents an effective and reasonably safe treatment for nonendogenous depression, although significant advantages over tricyclics with this disorder remain to be demonstrated.