Cortisol in Saliva (Free Cortisol)
This test measures the amount of free cortisol, a form of the stress hormone cortisol, present in your saliva. It helps assess your body’s natural cortisol levels over time, often used to evaluate adrenal function and stress responses.
["Measuring salivary cortisol helps diagnose conditions linked to abnormal stress hormone levels."]
Key facts at a glance
- LOINC
- 18365-7
- Short code
- Cortis F Sal-mCnc
- Synonyms
- Cortis F Sal-mCnc
- 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 Is This Test Done?
Your healthcare provider may order this test if you have symptoms like unexplained fatigue, weight changes, or mood swings that might suggest hormonal imbalances. It’s also used in research or clinical settings to monitor cortisol levels during stress or sleep studies.
What to Expect Before the Test
No special preparation is needed. You’ll provide a saliva sample, usually collected in the morning when cortisol levels are naturally highest. Avoid caffeine or smoking for a few hours before collecting the sample to ensure accurate results.
How the Test Works
A small amount of saliva is collected using a special device. The test measures free cortisol, which isn’t bound to proteins in the blood, allowing for more reliable results.
What the Results Mean
Results help determine if your cortisol levels are too high or too low, which can indicate conditions like Cushing’s syndrome (high cortisol) or adrenal insufficiency (low cortisol). 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.
Clinical Significance: Cortisol is a key hormone produced by your adrenal glands in response to stress. Abnormal levels can affect energy, metabolism, immune function, and mood. Salivary cortisol testing provides a more natural measure of daily hormone fluctuations compared to blood tests.
Short name
Salivary Free Cortisol
Frequently asked questions
Why might my doctor recommend this test?
How often will I need this test?
Can I take anything before the test?
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 16, 2026. · Read our editorial policy