Could it be my thyroid?
If you’re living with depression or bipolar disorder and it’s not getting better with treatment, your mood could be the result of a thyroid disorder. Women are up to eight times more likely to have the condition. In fact, Oprah recently revealed that she had been treated for hypothyroidism, which caused weight gain and other health problems.
Thyroid hormone, which regulates your metabolism and heart rate, is produced by the small, butterfly-shaped thyroid gland in the front of your neck.
If you have a thyroid problem, your symptoms may include weight gain or loss, sensitivity to hot or cold, bowel movement changes and menstrual irregularities. See Symptoms. It can also affect your mood. Too little thyroid (hypothyrodism) can cause depression or symptoms of bipolar mixed states and rapid-cycling; too much (hyperthyroidism) can cause anxiety. Most people who have thyroid disease are hypothyroid.
How does thyroid treatment work?
To treat hypothyroidism, medication can replace missing thyroid hormone or, for hyperthyroidism, can block production of new thyroid hormone, improving both emotional and physical symptoms. Studies have shown thyroid can act as an antidepressant and perhaps also as a mood stabilizer.
Thyroid pills contain the same molecule that your thyroid makes. Cytomel is T3, which is thought to act as an antidepressant. Levothyroxine is T4, which tends to act more like a mood stabilizer. There’s also a medication made from animal thyroid, which contains both T3 and T4. “We don’t know as much about how animal thyroid works because it has two variables,” says psychiatrist Jim Phelps, author of the book Why Am I Still Depressed?.
“Low-dose T3 is used to treat unipolar and bipolar depression, sometimes as an add-on to an antidepressant. T4, in high doses, has been found in preliminary studies to be effective with treatment-resistant and rapid-cycling bipolar symptoms,” says Dr. Phelps.
Thyroid’s use for mood disorders is controversial. But, some doctors have found it to be effective when other treatments haven’t worked, even if lab tests don’t show a thyroid imbalance. “Thyroid stimulating hormone (THS), our basic measure of thyroid function, is involved in a lot more than just telling the thyroid gland to make more thyroid hormones,” says Dr. Phelps. “Somehow the whole TSH system seems to be changed when the hormones come from the outside instead of the inside. Some patients seem to get better even when they start with TSH values that are clearly “normal” by standard lab tests.”
Thyroid has no side effects or risks, as long as your levels remain in the normal range. “There aren’t many treatments for depression or bipolar disorder that are harmless,” says Dr. Phelps. Your doctor will monitor to make sure you aren’t taking too much or too little. Abnormal heart rhythm and decreased bone-density are theoretical long-term risks if your dose is too high.