Cortisol, Serum or Plasma, Mass Concentration
This test measures the amount of cortisol, a hormone produced by your adrenal glands, in your blood. Cortisol helps regulate metabolism, immune response, and stress reactions.
["Cortisol helps manage stress and supports normal body functions, and this test helps doctors assess adrenal gland health or hormone imbalances."]
Key facts at a glance
- LOINC
- 2145-1
- Short code
- Cortis F SerPl-mCnc
- Synonyms
- Cortis F 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 Is This Test Done?
Your doctor may order this test to check for conditions like Cushing’s syndrome (too much cortisol), Addison’s disease (too little cortisol), or to monitor treatment for hormone-related disorders. It can also help diagnose issues with your adrenal glands or pituitary gland.
What to Expect Before the Test
No special preparation is usually needed, but if your doctor suggests timing it around certain activities (like stress events), follow their instructions. Blood is drawn from a vein, typically in your arm, and you may feel a slight pinch.
What Happens During the Test?
A healthcare provider will clean the area, insert a small needle into your vein, and collect a blood sample. The process takes a few minutes, and you can usually resume normal activities afterward.
What Are Possible Results?
Results will be compared to standard ranges for cortisol levels in blood. Abnormal results may indicate hormonal imbalances or other health concerns that need further evaluation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: Cortisol plays a vital role in managing stress, immune function, and metabolism. High cortisol levels may suggest conditions like Cushing’s syndrome, while low levels could indicate Addison’s disease or other adrenal or pituitary issues. Your doctor will interpret results in the context of your symptoms and medical history.
Short name
Cortisol Level
Frequently asked questions
What does a cortisol test measure?
How is cortisol tested?
Can cortisol levels change based on when the test is taken?
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