Cortisol is an adrenal hormone responsible for controlling the glucose metabolism in the body. It also plays a key role in maintaining the stress levels, blood pressure, and immunity of an individual. The Cortisol Serum test is conducted to check the levels of this hormone in the blood. It helps in diagnosing the diseases like Addison’s disease and Cushing’s disease which disturb the cortisol levels. The blood sample taken for the morning test ranges from 6 to 23 micrograms per decilitre. The results are provided in normal, higher than normal, and lower than normal denomination.