Insulin is supposed to lower blood glucose level. With excessive insulin treatment, an abnormally low blood glucose level called hypoglycemia occurs. However, with prolonged insulin treatment, the body tends to counter the physiological effect of insulin. The body is stimulated to release epinephrine, ACTH, glucagon and growth hormone. With their release, the liver is stimulated to convert stored glycogen into glucose. Thus, the outcome is a rebound hyperglycemia or high blood glucose level following hypoglycemia.