Background: An 8-week open trial was conducted to investigate whether patients with treatment-resistant, chronic depression and/or dysthymia could profit from high-dose thyroxine (T4) augmentation.
Methods: Nine patients whose current depressive episode had lasted for a mean of 15.5 +/- 8.6 months (range: 2-30 months) received T4 in addition to their current medication.
Results: Two patients dropped out of the study owing to side effects. The remaining 7 patients received a final mean dose of T4 of 235 +/- 58 micrograms/day (range: 150-300 micrograms/day). Their scores on the Hamilton Depression Rating Scale had fallen from a mean of 21.1 +/- 4.1 before inclusion in the study to a mean of 8.0 +/- 2.8 at the end of the 8th week. Five patients were full responders, 1 a partial responder, and 1 a nonresponder.
Conclusions: Augmentation with high-dose T4 proved to have an antidepressant effect in more than 50% of the previously treatment-resistant patients with chronic depression and/or dysthymia.