Depressed + Need More T3?
Last week I had a patient with normal T3 levels tell me that her shrink decided to give her a hefty dose of cytomel in addition to her Selective Serotonin Reuptake Inhibitor (SSRI) to see if it would help with her depression.
WTF? Never heard of it, so I thought I’d investigate and share my findings with you.
Turns out that patients with normal thyroid function who are treated with Prozac and Zoloft experience a significant drop in their T3 at 15 and 30 days after treatment is started (de Carvalho et al., 2009). No such change was noticed in hypothyroid patients treated with these SSRIs.
Other studies have shown that in patients treated with SSRIs who don’t respond, adding T3 can help their depression. In one study from my old stomping grounds at Harvard, Massachusetts General Hospital, 39% improved (Iosifescu et al., 2008). However, a larger review of all data including 5 randomized trials (the best quality evidence) reports that T3 aumentation cannot conclusively be said to improve depression in patients on SSRIs (Cooper-Kazaz and Lerer, 2008). In other words, the jury is still out.
If you’re on an SSRI, has your prescribing doctor offered T3? Should you be on an SSRI? I believe SSRIs are overprescribed. I believe they are needed for severe depression but may be worse than placebo for mild to moderate depression. Did you catch the news in April that anti-depressants are associated with an 11% increased risk of breast and ovarian cancer (Cosgrove, 2011). After pouring over 61 studies of anti-depressants, lead author Lisa Cosgrove of the Harvard Center for Ethics also found an important link between researchers who are affiliated or unaffiliated with pharmaceutical companies. Among “clean” researchers, with no ties to pharmaceutical companies, 43% had a positive link between antidepressant use and breast/ovarian cancer. And the affiliated researchers? 0% found a link between antidepressants and breast/ovarian cancer. You read it right: 0%. Conflict of interest? Perhaps.
Anti-depressants are prescribed more widely than just for depression. I was taught in my medical training to use them for hot flashes (particularly… get this, in breast cancer survivors who can’t take estrogen), headache, back pain, anxiety, eating disorders such as bulimia, fibromyalgia. Time to rethink the SSRI program in this country, where 11% of our population is on an SSRI, and most of them are women.
Cooper-Kazaz R, Lerer B. Efficacy and safety of triiodothyronine supplementation in patients with major depressive disorder treated with specific serotonin reuptake inhibitors. Int J Neuropsychopharmacol. 2008 Aug;11(5):685-99. Epub 2007 Nov 30.
Cosgrove L, Shi L, Creasey DE, Anaya-McKivergan M, Myers JA, Huybrechts KF. Antidepressants and breast and ovarian cancer risk: a review of the literature and researchers’ financial associations with industry. PLoS One. 2011 Apr 6;6(4):e18210.
Iosifescu DV, Bolo NR, Nierenberg AA, Jensen JE, Fava M, Renshaw PF. Brain bioenergetics and response to triiodothyronine augmentation in major depressive disorder. Biol Psychiatry. 2008 Jun 15;63(12):1127-34. Epub 2008 Jan 22.
de Carvalho GA, Bahls SC, Boeving A, Graf H. Effects of selective serotonin reuptake inhibitors on thyroid function in depressed patients with primary hypothyroidism or normal thyroid function. Thyroid. 2009 Jul;19(7):691-7.
Written by, Dr. Sara Gottfried