Cortisol, Free, 24-Hour Urinary Total

Why This Test Matters

Cortisol is a key hormone produced by your adrenal glands, which sit on top of your kidneys. It plays a role in managing stress, immune response, and metabolism. Measuring cortisol in urine over a full day gives a more accurate picture of your body’s natural cortisol levels, rather than just a single blood sample.

What to Expect Before the Test

You’ll collect all urine for a full 24-hour period, starting right after you wake up and ending just before you wake up again the next day. Keep a record of the time each urine sample is collected. Drink plenty of fluids to help your body produce enough urine, but avoid caffeine or alcohol, as they can affect results.

What the Test Results Mean

Results help doctors identify whether your cortisol levels are too high or too low. High levels might suggest conditions like Cushing’s syndrome, while low levels could indicate adrenal insufficiency or other hormonal issues. Your doctor will interpret results in the context of your symptoms and medical history.

Common Conditions This Test Helps Diagnose

This test is often used to diagnose conditions like Cushing’s syndrome (caused by too much cortisol), primary or secondary adrenal insufficiency (caused by too little cortisol), and other adrenal or pituitary disorders. It can also help evaluate chronic stress or other hormonal imbalances.