The Safety and Efficacy of Combined Amitriptyline and Tranylcypromine Antidepressant Treatment

Sixty patients meeting DSM-III criteria for major depression were assigned randomly to double-blind treatment for four weeks according to fixed-dosage steps with (1) amitriptyline hydrochloride alone, up to a maximum dosage of 300 mg/day; (2) tranylcypromine alone, up to 40 mg/day; or (3) the combination of amitriptyline hydrochloride, up to 150 mg/day, and tranylcypromine, up to 20 mg/day. The conditions of patients in all three treatment groups improved equally. The combined treatment did not produce a higher frequency of side effects, and no side effects, such as hypertensive or hyperthermic crises, occurred in any patient. Both amitriptyline alone and combined treatment produced substantially more anticholinergic side effects than did tranylcypromine. These results support the safety and efficacy of the combined treatment, although claims for superior efficacy over single-antidepressant treatments in this heterogenous population were not supported.