Methods for monitoring pituitary function and for distinguishing Cushing's disease from Cushing's syndrome. The methods includes (1) providing a subject, (2) administering to the subject a daily dosage of a glucocorticoid antagonist, (3) monitoring adrenocorticotropic hormone (“ACTH”) and/or cortisol levels in the subject. Subjects having normal pituitary function typically show an increase in ACTH and/or cortisol levels following glucocorticoid antagonist therapy, while subjects having abnormal pituitary function will typically show no significant change in ACTH or cortisol following glucocorticoid antagonist therapy. Similarly, subjects having Cushing's disease show a significant rise in ACTH and cortisol levels following glucocorticoid antagonist therapy, while, in contrast, subjects having Cushing's syndrome show no significant change in ACTH and/or cortisol following glucocorticoid antagonist therapy.
METHOD FOR MONITORING AND ASSESSING PITUITARY FUNCTION