Cortisol blood is drawn three times without fasting, the first time cortisol is drawn at 8:00 a.m., the second time at 4:00 p.m., and the third time at 00:00 in the morning. Normal blood cortisol values are highest at 8:00 am, lower at 4:00 pm than at 8:00 am, and lowest at 00:00 am. If the blood cortisol rhythm disappears, the 24-hour urine free cortisol should be perfected, and the blood ACTH should also be perfected, and the adrenal CT should also be perfected when considering adrenal disease if the 24-hour urine free cortisol is increased and the blood cortisol rhythm is problematic, and if there is only a simple problem with the blood cortisol rhythm, it may be simple obesity, and a low-dose dexamethasone test needs to be perfected to identify the problem. The test should be refined with a low-dose dexamethasone test to identify the problem.