The low dose (1 mu g) ACTH stimulation test for assessment of the hypothalamo-pituitary-adrenal axis

Traditional testing of the hypothalamo-pituitary-adrenal axis function has relied essentially upon the insulin tolerance test or the metyrapone challe nge: both tests are not only uncomfortable, but carry also real dangers. Th e standard ACTH stimulation test uses an extremely hyperphysiological amoun t (250 mu g) of ACTH to evaluate a physiologic response, which may result i n false normal responses. The proposed low dose (1 mu g) ACTH test is more physiological and more sensitive, especially in cases of mild adrenal insuf ficiency and allows also to assess pituitary-adrenal suppression after long -term treatment with glucocorticoids. According to the rules of evidence-ba sed medicine, the low dose ACTH test should replace the conventional 250 mu g test when evaluating for central adrenal insufficiency. (C) 2000 Elsevie r Science B.V. All rights reserved.