FAQ 3: What if my results are abnormal?
This test measures the amount of free (unbound) cortisol in your blood, which reflects your body’s current cortisol levels.
["Free cortisol helps assess adrenal function and potential hormone imbalances."]
Key facts at a glance
- LOINC
- 59047-1
- Short code
- F5 p.H1299R Bld/T Ql
- Synonyms
- F5 p.H1299R Bld/T Ql
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test to diagnose or monitor conditions like Cushing’s syndrome, adrenal insufficiency, or other hormonal disorders. It can also help evaluate cortisol levels during stress or after certain treatments.
What to Expect Before the Test
No special preparation is needed, but you may be asked to avoid certain medications or supplements that could affect results. If you’re taking steroids or other hormone-related drugs, let your doctor know.
How the Test Works
A blood sample is drawn from a vein in your arm. The sample is processed to separate free cortisol from other forms of cortisol in your blood.
What the Results Mean
Results are compared to standard reference ranges for free cortisol. Abnormal levels may indicate overproduction (e.g., Cushing’s) or underproduction (e.g., adrenal failure) of cortisol.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Inform your doctor immediately. They may recommend additional tests or adjustments to your treatment plan based on the findings.
Frequently asked questions
High free cortisol levels may suggest conditions like Cushing’s syndrome, where the body produces too much cortisol, or certain tumors affecting hormone production. Low levels could indicate adrenal insufficiency or pituitary disorders.
Low cortisol levels may require treatment to prevent serious complications, such as adrenal crisis.
No fasting is required, but you should avoid caffeine or alcohol for a few hours before the test, as they can temporarily affect cortisol levels.
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