Cortisol levels are normally regulated by the hypothalamus and pituitary gland. The hypothalamus sends corticotropin-releasing hormone (CRH) to the pituitary gland. The pituitary gland responds by producing several hormones, one of which is ACTH (corticotropin). ACTH stimulates the adrenal gland to produce cortisol. Cortisol levels help to control the pituitary's production of ACTH.
