Cortisol in Urine
Test OverviewA 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. Normally, cortisol levels rise during the early morning hours and are
highest about 7 a.m. They drop very low in the evening and during the early
phase of sleep. But if you sleep during the day and are up at night, this
pattern may be reversed. If you do not have this daily change in cortisol levels, you may have overactive adrenal glands. Cortisol levels vary widely throughout the day, so you collect urine over 24 hours for this test. Why It Is DoneA
cortisol test is done to find problems of the
pituitary gland or adrenal glands, such as making too much hormone. How To PrepareYou 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. Many medicines may change the
results of this test. Be sure to tell your doctor about all the
nonprescription and prescription medicines you take. Talk to your doctor about any concerns you have regarding the need
for the test, its risks, how it will be done, or what the results will mean. To
help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?). 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 1 gal (4 L). 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.
- Keep the large container
in the refrigerator for the 24 hours.
- Empty your bladder for the
final time at or just before the end of the 24-hour period. Add this urine to
the large container, and record the time.
- Do not get toilet paper,
pubic hair, stool (feces), menstrual blood, or other foreign matter in the
urine sample.
How It FeelsThis test does not cause any pain. RisksCollecting a 24-hour urine sample does not cause problems. ResultsA cortisol test measures the level
of the
hormone cortisol in a 24-hour sample of urine. NormalThese numbers are just a guide. The range for "normal" varies from lab to lab. Your lab may have a different range. Your lab report should show what range your lab uses for "normal." Also, your doctor will evaluate your results based on your health and other factors. So a number that is outside the normal range here may still be normal for you. High valuesHigh values of cortisol may be caused by: - Some medicines.
- Pituitary and adrenal tumors, 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 TestYou may not be able to have the test, or the results may not be helpful, if: - 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.
ReferencesCitations- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Other Works Consulted- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
CreditsByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Kathleen Romito, MD - Family Medicine
Specialist Medical ReviewerAlan C. Dalkin, MD - Endocrinology Current as of:
May 3, 2017 Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier. Last modified on: 8 September 2017
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