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24-Hour Urinary Free Cortisol

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

This test measures the amount of cortisol (a natural steroid hormone) you excrete in your urine over a 24-hour period.

Quick summary

["Helps assess adrenal gland function and cortisol production levels over time."]

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

Key facts at a glance

LOINC
25885-5
Short code
Cortis F 24h Ur HPLC-sRate
Synonyms
Cortis F 24h Ur HPLC-sRate
Category
hormone
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hplc
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your doctor may order a 24-hour urinary free cortisol test to check for conditions like Cushing’s syndrome, where the body produces too much cortisol, or adrenal insufficiency, where cortisol levels are too low. It can also help diagnose other hormonal imbalances or evaluate responses to treatments.

What to Expect Before the Test

You’ll need to collect all urine for 24 hours, typically starting with your first urine of the day. Store samples properly to prevent contamination. Follow your healthcare provider’s instructions carefully to ensure accurate results.

What Happens During the Test

After collecting your urine samples, they’ll be sent to a lab for analysis. The lab will measure cortisol levels in your urine using a specialized technique to detect even small amounts.

What the Results Mean

Results are compared to standard ranges for healthy individuals. High levels may suggest overproduction of cortisol, while low levels may indicate adrenal problems. Your doctor will interpret results in the context of your symptoms and medical history.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

24h Urinary Free Cortisol

Frequently asked questions

How long does it take to get the results?
Results typically take 1–2 weeks to return, depending on lab processing times and your healthcare provider’s workflow.
Can I take medications before this test?
Yes, but inform your doctor about all medications, including over-the-counter drugs or supplements, as they may affect cortisol levels. Follow their specific instructions for timing.
Is there anything I should avoid during urine collection?
Avoid excessive caffeine, alcohol, or certain medications that might alter cortisol levels. Also, ensure proper hygiene during collection to prevent contamination.
  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