A cortisol test measures the level of cortisol in your body. Cortisol, known as the stress hormone, is important to several bodily functions. Cortisol testing requires a sample of blood, urine, saliva or a combination, and the test often is repeated. Results outside the normal range might indicate Cushing’s syndrome, Addison’s disease or a tumor.
A cortisol test measures the level of cortisol in your body. Cortisol is a hormone made by your adrenal glands. The test determines whether you have too much or too little of the hormone.
The test requires a sample of blood, urine, saliva or a combination. The results can help healthcare providers diagnose:
A cortisol test is sometimes called:
Cortisol is a hormone made by the adrenal glands. It’s nicknamed the stress hormone because it helps you respond to stress. It also helps you:
Most cortisol is in the blood, attached to proteins. But some cortisol is “free” and present in the urine and saliva.
In a healthy person, cortisol rises and falls at different times of the day. It’s usually higher in the morning and lower at night unless a person works late or has changing shifts. Other events or factors can affect cortisol levels, including:
A cortisol test shows whether a person has high or low levels of cortisol, which may indicate an adrenal disorder.
A normal cortisol value in a blood sample taken at 8 a.m. is 5 to 25 mcg/dL. But results can vary widely, depending on the time of the test and the other factors that affect cortisol levels.
The symptoms of Cushing’s syndrome include:
The symptoms of Addison’s disease include:
Cortisol can be measured in the blood, urine, saliva or a combination. Your healthcare provider will tell you which test they recommend for you.
You may need to repeat cortisol testing twice in one day or multiple times over several days because cortisol levels vary.
Your healthcare provider will give you specific instructions. For example, you shouldn’t eat, drink or brush your teeth before a salivary test. You may need to rest beforehand so that stress doesn’t interfere with the results.
Blood tests involve minimal risk. Urine and saliva tests have no known risks.
Cortisol test results may take one to five days, depending on the healthcare provider and lab.
The outcome of cortisol testing can indicate several different things. Your healthcare provider will explain your results and what they mean.
High levels of cortisol might indicate:
Low levels of cortisol might indicate:
If your results are low or high, your healthcare provider may order other tests:
A note from Cleveland Clinic
A cortisol test measures the level of cortisol in your body. It can help diagnose an adrenal disorder such as Cushing’s syndrome or Addison’s disease. Your healthcare provider will give you specific instructions on the type of test you need and when it should happen.
Last reviewed by a Cleveland Clinic medical professional on 02/21/2022.
Learn more about our editorial process.