Sciatica, severe pain in the leg along the sciatic nerve and its branches. It may be caused by injury or pressure to the base of the nerve in the lower back, or by metabolic, toxic, or infecti...

Warfarin, anticoagulant used to treat blood clots. In large doses it causes bleeding, and in patients with genetic variations that increase sensitivity to the drug and decrease the rate at whi...

Metabolite, organic compound that is a starting material in, an intermediate in, or an end product of metabolism. Starting materials are substances, usually small and of simple structure, abso...

Hydrocortisone, another name for the steroid hormone cortisol, more especially used to refer to preparations of this hormone used medicinally. Hydrocortisone, introduced in 1952, is more poten...

Methotrexate, drug used in halting the growth of actively proliferating tissues. Introduced in the 1950s, it is used in the treatment of leukemia, psoriasis, and non-Hodgkin's lymphoma. By bin...

Thyroid gland, endocrine gland, situated in the neck, that secretes hormones necessary for growth and proper metabolism. It consists of two lobes connected by a narrow segment called the isthm...

Parathyroid glands, four small endocrine bodies, located behind the thyroid gland, that govern calcium and phosphorus metabolism. These four masses of tissue (each about the size of a pea) are...

Colchicine, alkaloid extracted from plants of the genus Colchicum and especially from the corms of the autumn crocus, Colchicum autumnale (see meadow saffron). The metabolic effect of colchici...

Epinephrine, hormone important to the body's metabolism, also known as adrenaline. Epinephrine, a catecholamine, together with norepinephrine, is secreted principally by the medulla of the adr...

Excretion, process of eliminating from an organism waste products of metabolism and other materials that are of no use. It is an essential process in all forms of life. In one-celled organisms...