The Cortisol/Creatinine Ratio (24-Hour Urine) test measures the ratio of cortisol to creatinine excreted in the urine over a 24-hour period. Cortisol is a hormone produced by the adrenal glands, and creatinine is a waste product generated from muscle metabolism, commonly used to assess kidney function. This ratio is used to evaluate the adrenal glands’ production of cortisol while accounting for variations in urine concentration, helping to correct for potential dilution or concentration of urine samples.

The test is often used to assess conditions such as Cushing’s syndrome (excess cortisol production) or adrenal insufficiency (low cortisol production), as it provides an indication of abnormal cortisol secretion over an entire day. It may also help monitor adrenal function and screen for disorders related to cortisol production.