Cortisone is one of several steroid hormones secreted by the cortex (outer covering) of the adrenal gland. These hormones, called corticoids, are classified according to their functions, glucocorticoids controlling sugar metabolism and mineralocorticoids controlling the metabolism of minerals and water. The principal glucocorticoids are corticosterone and hydrocortisone (cortisol) and the principal mineralocorticoid is aldosterone. Cortisone is in both categories, because it quickly converts protein to the carbohydrate glucose and it helps regulate salt metabolism. Cortisone also helps the body withstand stress. It is used medically to reduce inflammation.

The adrenal cortex's production of cortisone is controlled by the hormone ACTH (adrenocorticotropic hormone), which is secreted by the pituitary gland. The pituitary, in turn, responds to corticotropin-releasing factor, a hormone-like substance produced by the portion of the brain called the hypothalamus.

Knowledge of cortisone is due primarily to three scientists, the Swiss chemist Tadeus Reichstein and the Americans Edward...