Cortisol in Urine

Test Overview

A cortisol test measures the level of the hormone cortisol in a 24-hour sample of urine. The cortisol level may show problems with the adrenal glands or the pituitary gland. Cortisol is made by the adrenal glands. Cortisol levels get higher when the pituitary gland releases adrenocorticotropic hormone (ACTH).

Cortisol has many functions. It helps the body use sugar (glucose) and fat for energy (metabolism). It helps the body manage stress. Cortisol levels can be affected by many things, such as physical or emotional stress, strenuous activity, infection, or injury.


Cortisol levels vary widely throughout the day, so you collect urine over 24 hours for this test.

Why It Is Done


How To Prepare

You may be asked to avoid strenuous physical activity the day before the test.

Be sure to drink enough fluids during the 24-hour urine test. This prevents dehydration.



How It Is Done

  • You start collecting your urine in the morning. When you first get up, empty your bladder but do not save this urine. Write down the time that you urinated. This marks the beginning of your 24-hour collection period.
  • For the next 24 hours, collect all your urine. Your doctor or lab will usually provide you with a large container that holds about 4 L (1 gal). The container has a small amount of preservative in it. Urinate into a small, clean container and then pour the urine into the large container. Do not touch the inside of the container with your fingers.

How It Feels

This test does not cause any pain.


Collecting a 24-hour urine sample does not cause problems.





Cortisol level in a 24-hour urine samplefootnote 1


Less than 100 micrograms (mcg) or less than 276 nanomoles (nmol)


5–55 mcg or 14–152 nmol


2–27 mcg or 5–75 nmol

High values

High values of cortisol may be caused by:

  • Some medicines.
  • Pituitary and adrenal tumours, which are usually benign. This means they are not cancer.
  • Some types of cancer, such as adrenal cancer and some rare lung cancers.

What Affects the Test


  • You feel physical or emotional stress.
  • You are pregnant. This can cause urine cortisol levels to be high.
  • You have low blood sugar (hypoglycemia).
  • You eat, drink, or exercise before the test.
  • You take medicines such as estrogen, amphetamines, or corticosteroids.
  • You don't collect urine for exactly 24 hours.

What To Think About

  • A 24-hour urine test is used more often than a cortisol blood test to diagnose Cushing's syndrome. To learn more about a cortisol blood test, see the topic Cortisol in Blood.
  • Other tests can help find out if the pituitary gland or adrenal glands are working well. These include the adrenocorticotropic hormone (ACTH) and dexamethasone suppression tests.




Other Works Consulted



ByHealthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Kathleen Romito, MD - Family Medicine
Alan C. Dalkin, MD -

Current as ofMarch 15, 2018

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