Cortisol (serum/plasma, mass concentration)
This test measures the amount of cortisol, a natural steroid hormone produced by your adrenal glands. Cortisol helps regulate metabolism, immune response, and stress reactions.
["Cortisol helps manage stress and supports bodily functions, and this test checks your hormone levels."]
Key facts at a glance
- LOINC
- 1403-5
- Short code
- Cortis 1h p 250 ug ACTH IM SerPl-mCnc
- Synonyms
- Cortis 1h p 250 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 Is This Test Done?
Your doctor may order cortisol testing to diagnose or monitor conditions like Cushing’s syndrome (too much cortisol), Addison’s disease (too little cortisol), or adrenal gland issues. It can also help evaluate stress responses, hormone imbalances, or symptoms like weight changes, fatigue, or high blood pressure.
What to Expect Before the Test
No special preparation is needed for a cortisol blood test. You may be asked to fast for 8–12 hours before the draw if testing is done in the morning. If testing is for a 24-hour urine collection, follow your doctor’s instructions carefully, as it involves collecting urine over a full day.
What Happens During the Test?
A healthcare provider will draw blood from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause discomfort. For urine testing, you’ll collect all urine for a full 24-hour period in a container provided.
What Are Possible Results?
Results are interpreted by your doctor based on your symptoms, medical history, and other tests. Abnormal levels may indicate hormonal imbalances or conditions affecting your adrenal glands.
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 conditions like Cushing’s syndrome, where the body produces too much cortisol, or chronic stress. Low cortisol levels could indicate Addison’s disease, where the adrenal glands don’t produce enough hormones, or other adrenal dysfunctions. Your doctor will use these results alongside other tests to guide diagnosis and treatment.
Short name
Cortisol Level
Frequently asked questions
What Does a Cortisol Test Measure?
How Often Should I Get This Test?
Can Cortisol Levels Change Based on Time of Day?
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