Treatment of imipramine-resistant recurrent depression: I. An open clinical trial of adjunctive L-triiodothyronine.

Prior studies suggest that supplemental treatment with thyroid hormone may enhance the patient's response in depression resistant to tricyclic antidepressants. The authors report on the lack of efficacy of adjunctive L-triiodothyronine (T3; 25 micrograms/day) in a sample of 20 outpatient unipolar depressives who had not responded to greater than or equal to 12 weeks of treatment with imipramine (mean dosage = 240 mg/day) and interpersonal psychotherapy. The overall response rate after 4 weeks of T3 was low (25%); the outcome did not differ significantly from a matched historical comparison group who received continued tricyclic treatment but not T3.