Cortisol is a 17alpha-hydroxy-C21-steroid that is pregn-4-ene substituted by oxo groups at positions 3 and 20 and hydroxy groups at positions 11, 17 and 21. Cortisol is a corticosteroid hormone or glucocorticoid produced by zona fasciculata of the adrenal cortex, which is a part of the adrenal gland. It is usually referred to as the "stress hormone" as it is involved in response to stress and anxiety, controlled by corticotropin-releasing hormone (CRH). It increases blood pressure and blood sugar, and reduces immune responses It has a role as an anti-inflammatory drug, an anti-allergic agent, an anti-asthmatic drug, a human metabolite, a mouse metabolite and a drug allergen. It is a 21-hydroxy steroid, an 11beta-hydroxy steroid, a 20-oxo steroid, a 3-oxo-Delta(4) steroid, a primary alpha-hydroxy ketone, a tertiary alpha-hydroxy ketone, a 17alpha-hydroxy-C21-steroid and a glucocorticoid. It derives from a hydride of a pregnane.