This review summarizes the literature regarding T3-addition to tricyclic antidepressants (TCA) in patients with refractory depression. Two controlled (one placebo- and one T4-controlled), eight open and two case-studies were found. The results of the placebo-controlled study showed no difference in efficacy between T3- and placebo-addition. In the other controlled study T3-addition was significantly more effective than T4-addition in turning TCA-nonresponders into responders.

Open studies demonstrate a favorable response (50%) to this form of treatment in patients with TCA-resistant depression. More controlled studies are necessary to decide whether T3-addition deserves a place in the treatment protocol of (refractory) depression.