Below are references to some research/studies that have been done showing the active thyroid hormone T3 used in the treatment of depression.

1. Wilson, I.C., Prange, A.J. Jr., and Lara, P.P. L-triiodothyronine alone and with impramine in the treatment of depressed women. In The Thyroid Axis, Drugs, and Behavior. Edited by A.J. Prange. New York, Raven Press, 1974, pp.49-62.
2. Altshuler, L.L., Bauer, M., Frye, M.A., et al. Does thyroid supplementation accelerate tricyclic antidepressant response? A review and meta-analysis of the literature. Am. J. Psychiatry, 2001; 158:1617-1622.
3. Joffe, R.T. and Singer, W. A comparison of triidothyronine and thyroxine in the potentiation of tricyclic antidepressants. Psychiatry Res., 1990, 32:241-251.
4. Stern, R.A., Nevels, C.T., Shelhorse ,combined thyroid hormone treatment and electroconvulsive therapy: preliminary findings. Biol. Psychiatry, 1991, 30:623-627.
5. Cook, RG., Joffe, RT and Levitt AJ. “T3 augmentation of antidepressant treatmentin T4 replaced patients; J.,Clin.Pyschiatry 1992.53(1):16-
6. Lowe, J.C. The Metabolic Treatment of Fibromyalgia. Boulder: McDowell Publishing Co., 2000.
7. Lowe, J.C. and Honeyman-Lowe, G. Fibromyalgia and thyroid disease. Paper presented in Grenoble, France, May 6 (conference of the French Fibromyalgia Association of Rgion Rhne-Alpes) and discussed in Toulon, France on May 11 (at the Centre Hospitalier Intercommunal), 2000.
8. Lowe, J. Thyroid disease and fibromyalgia syndrome. Lyon Mditerrane Mdical: Mdecine du Sud-Est., 2000, 36(1):15-17, (Janvier, Fvrier, Mars) 2000.
9. Abraham G, Milev R, Stuart Lawson J.T3 augmentation of SSRI resistant depression.Department of Psychiatry, University of Toronto, ON, Canada
10. Joffe RT, Singer W, Levitt AJ, MacDonald C. A Placebo-Controlled Comparison of Lithium and Triiodothyronine Augmentation of Tricyclic Antidepressants in Unipolar Refractory Depression. Arch Gen Psychiatry. 1993;50(5):387-393. doi:10.1001/archpsyc.1993.01820170065008.
11. Thomas W. Heinrich, M.D. and Garth Grahm, M.D. Hypothyroidism Presenting as Psychosis: Myxedema Madness Revisited.
12. From the Department of Psychiatry and Behavioral Medicine, Medical College of Wisconsin, Milwaukee (Dr. Heinrich); and the Department of Internal Medicine, Massachusetts General Hospital, Harvard Medical School, Boston (Dr. Grahm) Prim Care Companion J Clin Psychiatry. 2003; 5(6): 260266. PMCID: PMC419396