Cortisol (Serum) with 24-Hour Urinary Free Cortisol Measurement
This test measures cortisol levels in your blood and urine to assess your body’s ability to produce and regulate cortisol, a hormone involved in stress response and metabolism.
["Helps diagnose adrenal gland issues, Cushing’s syndrome, or adrenal insufficiency by checking cortisol production over time."]
Key facts at a glance
- LOINC
- 1422-5
- Short code
- Cortis 3D p 500 ug ACTH IM SerPl-mCnc
- Synonyms
- Cortis 3D p 500 ug ACTH IM SerPl-mCnc
- Category
- hormone
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 60
- 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 Matters
Cortisol is a hormone produced by your adrenal glands, which sit on top of your kidneys. It helps your body respond to stress, regulate metabolism, and maintain blood pressure. When cortisol levels are too high or too low, it can cause serious health problems, such as weight changes, fatigue, or hormonal imbalances.
Blood Test: Serum Cortisol Levels
Your blood sample will be taken to measure cortisol at specific times (often early morning and late evening) to see how your body naturally produces this hormone. This helps identify whether cortisol levels are consistently high or low, which may indicate conditions like Cushing’s syndrome or adrenal insufficiency.
Urine Test: 24-Hour Free Cortisol
A 24-hour urine sample will be collected to measure cortisol that naturally passes into your urine. This test provides a total picture of cortisol excretion over a full day, which can help confirm whether cortisol production is excessive or insufficient.
What to Expect Before the Test
No special preparation is needed for the blood test, but for the urine test, you’ll need to collect all urine for a full 24-hour period. Follow your healthcare provider’s instructions carefully to ensure accurate results.
Reference range
NCBI: ACTH 10-60 pg/mLN/A
Typically collected in the morning (8-10 AM). Inform your provider if taking steroid medications.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
High cortisol levels may suggest Cushing’s syndrome (due to excess hormone production) or other causes like long-term stress or certain medications. Low cortisol levels could indicate adrenal gland problems, such as Addison’s disease, where the body fails to produce enough cortisol. Early detection can lead to timely treatment and improved quality of life.
Short name
Cortisol Profile
Frequently asked questions
What does a cortisol test tell me about my health?
Will I need to take any special steps before the test?
Can stress affect my cortisol test results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 17, 2026. · Read our editorial policy