Abstract

Metyrapone (Metopirone - Ciba) is used to test corticotrophin (ACTH) activity when pituitary insufficiency is suspected. It elicits an exaggerated adrenocorticotrophic response only in patients in whom the anterior pituitary and adrenal cortex are functioning normally. If in preliminary tests injected corticotrophin increases production of corticosteroids, then failure of metyrapone to do so is taken to indicate inadequate pituitary function.