Liothyronine is a naturally occurring hormone produced by the thyroid. It is important for
normal energy and metabolism. For a variety of reasons, the body may not produce enough of this
hormone on its own. In these cases, liothyronine is taken to replace the body's natural thyroid
hormone.
Liothyronine is used to treat hypothyroidism (low thyroid function). Liothyronine is also
used to prevent and treat goiter (growth or enlargement of the thyroid gland). Causes of goiter
include hormonal imbalances, radiation, surgery, and cancer.
Liothyronine may also be used for purposes other than those listed in this medication guide.