Enhancement of Imipramine by Thyroid Stimulating Hormone: Clinical and Theoretical Implications

Abstract

Thyroid stimulating hormone, when combined with imipramine, produces a more rapid recovery from depression than does imipramine alone. It seems more potent than triiodothyronine in potentiating imipramine, but dose differences prevent accurate comparison. This hormone has the clinical disadvantage of being long acting and difficult to control. Depressed patients show thyroid indices within the normal range. Serum indices of thyroid state respond normally to TSH injection, but ankle reflex time is not accelerated. Tantalizing clues have appeared, but the mechanism by which thyroid hormones potentiate tricyclic antidepressants remains unknown.