Metyrapone is primarily used in medical diagnostics to assess the function of the adrenal glands. It works by inhibiting an enzyme involved in cortisol production, leading to a decrease in cortisol levels. This allows doctors to evaluate the adrenal gland's response and diagnose conditions like Cushing's syndrome or adrenal insufficiency. Additionally, it is sometimes used in the treatment of Cushing's syndrome to manage excessive cortisol production. In research, metyrapone is utilized to study the hypothalamic-pituitary-adrenal axis and its role in stress responses. Its ability to modulate cortisol levels makes it a valuable tool in both clinical and experimental settings.