Lithium Therapy for Mood Disorder and Effects on the Thyroid Gland

Course Summary

Lithium is used as a long-term therapy and treatment of bipolar affective disorder. It is also used to treat other mental illnesses such as depression and schizophrenia. Lithium is known to potentially affect thyroid function. Depending on the signals from the pituitary gland, the thyroid gland produces more or less of T3 and T4. High levels of T3 and T4 levels leads to hyperthyroidism, while low T3 and T4 in the body causes hypothyroidism. Lithium can impact thyroid function in several ways. It may increase iodine content within the thyroid gland, reduce the thyroid gland’s ability to produce thyroxine (T4) and triiodothyronine (T3), block the release of thyroid hormones from the thyroid gland, and alter the structure of the protein thyroglobulin, which is involved in the making of thyroid hormone in the thyroid gland. Due to these effects, lithium may cause goiter as well as hypothyroidism. It is also linked to hyperthyroidism in some people, although this is rare.