A PLACEBO-CONTROLLED COMPARISON OF LITHIUM AND TRIIODOTHYRONINE AUGMENTATION OF TRICYCLIC ANTIDEPRESSANTS IN UNIPOLAR REFRACTORY DEPRESSION

Objective: To directly compare the efficacy of lithium carbonate and l iothyronine sodium (triiodothyronine) in the augmentation of therapeut ic response in antidepressant nonresponders. Design: A randomized, dou ble-blind, placebo-controlled study of 2 weeks' duration. Setting: The Mood Disorders Program, Clarke Institute of Psychiatry and the Univer sity of Toronto, Ontario. Patients: Fifty outpatients, males and femal es, with unipolar, nonpsychotic major depression who had failed to res pond to treatment with desipramine hydrochloride or imipramine hydroch loride. Results: Both liothyronine and lithium were more effective tha n placebo in reducing scores on the Hamilton Rating Scale for Depressi on, However, the antidepressant augmenting effect of these two compoun ds did not differ from each other. When response was defined as a 50% or more reduction in the Hamilton Rating Scale for Depression scores a nd a final score less than 10, we found that 10 of 17 subjects respond ed to liothyronine, nine of 17 responded to lithium and three of 16 re sponded to placebo. Conclusions: Our study suggests that both lithium and liothyronine may be considered as alternatives in augmenting antid epressant response in patients who do not respond to treatment with a tricyclic antidepressant.