Cortisol, Serum Free (High-Sensitivity)
This test measures the amount of free cortisol, a form of the hormone cortisol that circulates freely in your blood. Free cortisol is important for regulating stress responses, metabolism, and other bodily functions.
["Free cortisol helps your body manage stress and maintain balance in your hormones."]
Key facts at a glance
- LOINC
- 47846-1
- Short code
- Cortis p 2 mg Dex high SerPl-mCnc
- Synonyms
- Cortis p 2 mg Dex high SerPl-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 This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms like unexplained fatigue, weight changes, or mood swings that could be linked to hormonal imbalances. It may also be used to diagnose or monitor conditions such as Cushing’s syndrome, adrenal insufficiency, or other hormonal disorders.
What to Expect Before the Test
No special preparation is needed for this test. You’ll have a small needle inserted into your arm to draw blood. If you’re taking medications that affect cortisol levels (like steroids), let your provider know before the test.
What the Results Mean
Results are interpreted by your healthcare provider based on your symptoms and medical history. Elevated or low levels may indicate conditions requiring further evaluation or treatment.
Common Conditions Monitored
This test is often used to diagnose or evaluate conditions like Cushing’s disease (too much cortisol), Addison’s disease (too little cortisol), or to check cortisol levels during stress or recovery phases.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Free Cortisol
Frequently asked questions
Cortisol is a steroid hormone produced by your adrenal glands. It helps your body respond to stress, regulates metabolism, and supports immune function. Free cortisol is the active form that directly affects these processes, so measuring it helps identify whether your hormone levels are too high or too low.
No specific dietary restrictions apply, but if you’re taking medications that might influence cortisol levels (like certain antidepressants or steroids), inform your provider before testing.
Results typically take 1–3 business days, depending on your lab’s processing time. Your provider will discuss them with you during your follow-up visit.
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