• The best test of the response to stress, when done carefully, is measurement of plasma cortisol levels during insulin-induced hypoglycemia [24]. This is is probably the most sensitive test of adrenal suppression, and is most frequently abnormal for long periods after corticosteroid use [13,16]. (See card "Insulin-induced hypoglycemia test"). However, insulin-induced hypoglycemia is difficult to perform and carries some risk if not done properly. It is, at present, not commonly used in clinical practice.