24-Hour Urinary Free Cortisol

Why This Test Matters

Cortisol is a hormone that helps your body respond to stress. A 24-hour urine test for cortisol is often used to detect long-term cortisol imbalances that simple blood tests might miss. This test is especially useful for identifying conditions like Cushing’s syndrome, where the body produces too much cortisol, or adrenal insufficiency, where cortisol levels are too low.

How the Test Works

You’ll collect your urine for a full 24-hour period, typically starting and ending at the same time each day. The collected urine is then sent to a lab for analysis. This method provides a more accurate picture of your cortisol levels throughout the day compared to a single blood test.

Preparation Tips

Follow your healthcare provider’s instructions carefully. You’ll need to collect all urine produced during the 24-hour period, including the first urine of the next day if the test starts at midnight. Store the urine in a cool place until you return it to the lab.

What to Expect During the Test

You’ll likely receive a collection kit with containers and instructions. Some kits may include preservatives to keep the urine stable. Make sure to label each container with the date and time the urine was collected. Avoid missing any urine, as this can affect the results.