Adrenocorticotropic Hormone (ACTH) analysis is a blood test that measures the level of ACTH, a hormone produced by the pituitary gland. This hormone is essential for regulating cortisol production from the adrenal glands, which is an important hormone affecting many vital functions in the body, such as stress response and immune function. ACTH testing is used to diagnose various conditions, including Cushing’s syndrome, where cortisol levels are elevated, and Addison’s disease, where cortisol levels are low. This test helps physicians assess endocrine health and understand the potential causes of hormonal disorders, facilitating the development of an appropriate treatment plan.