A medication employed to assess the activity of the adrenal glands. Tetracosactide mimics the natural hormone corticotropin (ACTH) through its chemical structure. ACTH plays a role in prompting the adrenal gland cortices to release hormones like cortisol. To detect potential adrenal gland issues, an injection of tetracosactide is administered, and the blood cortisol level is gauged. A lack of elevation in the cortisol level signifies an irregularity.