Test Overview A cortisol test is done to measure the level of the hormone adrenal glands pituitary gland adrenal glands pituitary gland adrenocorticotropic hormone
Cortisol has many functions. It helps the body use sugar (glucose) and fat for energy (metabolism
Normally, cortisol levels rise during the early morning hours and are highest about 7 a.m. They drop very low in the evening and during the early phase of sleep. But if you sleep during the day and are up at night, this pattern may be reversed. If you do not have this daily change (diurnal rhythm) in cortisol levels, you may have overactive adrenal glands. This condition is called Cushing's syndrome
The timing of the cortisol test is very important because of the way cortisol levels vary throughout a day. If your doctor thinks you might make too much cortisol, the test will probably be done late in the day. If your doctor thinks you may not be making enough, a test is usually done in the morning.
Why It Is Done
A cortisol
How To Prepare
You may be asked to avoid strenuous physical activity the day before a cortisol test. You may also be asked to lie down and relax for 30 minutes before the blood test.
Some medicines, such as steroids, can affect cortisol levels for some time even after you stop taking the medicine.
Load More Information about Cortisol in Blood Test
How It Is Done
A health professional uses a needle to take a blood sample, usually from the arm.
Watch How It Feels
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.
Risks
There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
Results
Normal Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.
High values A high level of cortisol in the blood can mean Cushing's syndrome corticosteroids A high blood cortisol level can be caused by severe liver or kidney disease, depression hyperthyroidism obesity Pregnancy or birth control pills can also cause a high blood cortisol level. Conditions such as recent surgery, illness, injury, or whole-body infection (sepsis) can cause high cortisol levels. Low values A low level of cortisol in the blood can be caused by:Problems that affect the adrenal glands directly, such as Addison's disease Problems with the pituitary gland Related Information
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Current as of: April 30, 2024
