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Cortisol, 24-Hour Urinary Free

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of cortisol, a natural steroid hormone, excreted in your urine over a 24-hour period. It helps assess your body’s cortisol production and adrenal gland function.

Quick summary

["Understanding your cortisol levels over time can help diagnose conditions related to stress, hormone imbalances, or adrenal disorders."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
55473-3
Short code
Cortis 3h p chal SerPl-sCnc
Synonyms
Cortis 3h p chal SerPl-sCnc
Category
hormone
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Doctors may order a 24-hour urinary cortisol test to diagnose conditions like Cushing’s syndrome (too much cortisol), Addison’s disease (too little cortisol), or to evaluate chronic stress responses. It’s also used to monitor treatment effectiveness for hormone-related disorders.

What to Expect Before the Test

You’ll collect your urine for 24 hours, starting and ending at the same time each day. Store the urine in a refrigerator or freezer until you deliver it to the lab. Follow any specific instructions your doctor provides, such as avoiding certain medications or foods that might affect results.

What Happens During the Test

No special preparation is needed beyond collecting urine over 24 hours. The lab analyzes the total cortisol excreted in your urine sample to determine your average daily production.

What the Results Mean

Results are compared to standard ranges for healthy adults. Elevated levels may indicate overproduction of cortisol, while low levels could suggest adrenal insufficiency or other hormonal issues. Your doctor will interpret the results in the context of your symptoms and medical history.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

How long does it take to get my results?
Results are typically available within 1 to 3 business days, depending on your lab’s processing time. Your doctor will contact you once they’re ready for review.
Can I take certain medications before this test?
Some medications, like certain steroids or blood pressure drugs, may affect cortisol levels. Always inform your doctor or lab technician about all medications, supplements, or recent treatments you’re taking.
Is there anything I should avoid before collecting my urine?
Avoid excessive caffeine, alcohol, or smoking for 24 hours before testing, as they can temporarily alter cortisol excretion. Also, empty your bladder before starting the collection to ensure accurate results.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy