Thyroid hormone treatment of primary unipolar depression: a review.

A substantial number of depressed patients will fail to respond to standard antidepressant therapy. Thyroid hormones, particularly T3, may be particularly useful in enhancing response to antidepressants. This review focuses on the use of T3 augmentation in unipolar major depression. The study clearly suggests that approximately half of patients will respond to T3 augmentation of antidepressants. There are several limitations to the literature including the fact that most studies have used T3 in tricyclic rather than SSRI failure and most are of relatively short duration, up to 3 wk. Further studies are required of T3 efficacy with newer classes of antidepressants, optimal dose of T3 to be used and the duration of T3 augmentation, particularly if the acute trial is successful.