24-Hour Urine Free Cortisol

Why This Test Matters

Cortisol is a hormone produced by your adrenal glands, which sit on top of your kidneys. It helps your body respond to stress and regulate processes like blood pressure, immune function, and energy levels. Measuring cortisol in urine over 24 hours gives a more accurate picture of your body’s natural cortisol production, as levels can fluctuate throughout the day.

How the Test Works

You’ll collect all your urine for a full 24-hour period in a special container. The test measures the total cortisol excreted in that time, rather than just cortisol levels at one point in time. This helps doctors detect any imbalances in cortisol production that might indicate health issues.

Common Uses

Doctors may order this test if they suspect conditions like Cushing’s syndrome (too much cortisol), adrenal insufficiency (too little cortisol), or other hormonal imbalances. It’s also used to monitor treatment effectiveness for conditions affecting cortisol levels.

What to Expect

You’ll receive clear instructions on how to collect your urine sample. Typically, you’ll start by emptying your bladder at the beginning of the 24-hour period and then collect all urine until you finish at the end of the day. Store the samples properly to preserve accuracy.