If you have an underactive thyroid gland, it means that your thyroid does not produce enough thyroid hormone. This is a condition known as hypothyroidism. Liothyronine restores the balance of thyroid hormone in your body. It is similar to thyroxine, the hormone which your body produces naturally. Although a medicine called levothyroxine is usually prescribed in preference to liothyronine for people with this condition, liothyronine is given when a fast action is needed, as it works more quickly.
This is a companion discussion topic for the original article at https://patient.info/medicine/liothyronine-tablets-and-capsules