Phenelzine and amitriptyline: effects on symptoms of neurotic depression

A double-blind controlled trial of phenelzine, amitriptyline and placebo was carried out in out-patients suffering from depression or mixed anxiety and depression. After six weeks treatment both active drugs were clearly superior to placebo and of similar efficacy; therapeutic effects started to appear at two weeks. Comparisons on symptom ratings showed that both drugs acted as true antidepressants, producing their greatest effects on ratings of depressive mood and thought content. There were additional weak differences, phenelzine producing more improvement on anxiety ratings, while amitriptyline gave greater effects on depressive impairment of work and interests and anergia. Analyses showed little evidence of clinical subgroups responding preferentially to either drug. The findings indicate that MAO inhibitors and tricyclic antidepressants have more closely similar clinical effects than has been thought and that either may be a useful treatment for these patients who are often considered to respond poorly to antidepressant drug treatment.