Cortisol in Blood Test

Test Overview

A cortisol test is done to measure the level of the hormone, Opens dialog cortisol in the blood. The cortisol level may show problems with the adrenal glands, Opens dialog or pituitary gland, Opens dialog. Cortisol is made by the adrenal glands, Opens dialog. Cortisol levels go up when the pituitary gland, Opens dialog releases another hormone called adrenocorticotropic hormone, Opens dialog (ACTH).

Cortisol has many functions. It helps the body use sugar (glucose) and fat for energy (metabolism, Opens dialog), and it helps the body manage stress. Cortisol levels can be affected by many conditions, such as physical or emotional stress, strenuous activity, infection, or injury.

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, Opens dialog.

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.

Information about Cortisol in Blood Test

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

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