What is "levothyroxine"

n. (context medicine English) The synthetic form of the thyroid hormone, thyroxine

Levothyroxine, also known as -thyroxine, is a synthetic thyroid hormone that is chemically identical to thyroxine (T), which is naturally secreted by the follicular cells of the thyroid gland. It is used to treat thyroid hormone deficiency, and occasionally to prevent the recurrence of thyroid cancer. Like its naturally secreted counterpart, levothyroxine is a chiral compound in the L-form. The related drug dextrothyroxine (-thyroxine) was used in the past as a treatment for hypercholesterolemia (elevated cholesterol levels) but was withdrawn due to cardiac side effects.

It is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system.