Adrenal corticosteroid inhibitors are drugs that inhibit key steps in the biosynthesis of hormones produced by the adrenal cortex, such as mineralocorticoids, glucocorticoids, estrogen and androgen. Adrenal corticosteroid inhibitors block one or more enzymes in the steroid synthesis pathway. They are used to treat Cushing's syndrome and some types of cancers. They are also used as diagnostic tools, such as in procedures to check pituitary function.