ACTH (adrenocorticotropic hormone) is a hormone produced by the pituitary gland, located below the brain. ACTH activates glands on the kidneys (adrenal glands) to make cortisol, a substance that helps the body deal with stress.
When cortisol levels in the blood rise, the ACTH levels in a healthy person normally fall in response. When cortisol levels decrease, ACTH levels normally rise.
Medical Review:Adam Husney MD - Family Medicine & E. Gregory Thompson MD - Internal Medicine & Brian D. O'Brien MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Alan C. Dalkin MD - Endocrinology