Cortisol Test

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.

What is Cortisol? #

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:

• Fight infection.

• Maintain blood pressure.

• Regulate blood sugar and metabolism (how your body processes food to create energy).

What is a Cortisol test? #

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:

• Addison’s disease, also known as hypocortisolism or primary adrenal insufficiency. This condition happens when your body has too little cortisol.

• Cushing’s syndrome, also called hypercortisolism. The condition occurs when your body has too much cortisol.

• Tumor affecting the production of cortisol. Various tumors may cause high cortisol levels.

How does a Cortisol test work? #

Cortisol can be measured in the blood, urine, saliva or a combination. Your healthcare provider will tell you which test they recommend for you.

• Blood test: In an office, clinic or lab, a healthcare provider inserts a thin needle into a vein in your arm. The needle collects a small sample of blood into a tube. You might feel a slight sting when the needle goes in.

• Saliva test: You or a healthcare provider puts a swab in your mouth and waits a few minutes until the swab is saturated with spit. If you do the test yourself at home, your healthcare provider will give you a special kit. They’ll tell you what time to perform the test and how to return the sample.

• Urine test: Your healthcare provider gives you a container to collect your pee. Most urinary cortisol tests collect all the pee you produce in 24 hours. Your healthcare provider may ask you to store the urine in a cold place, then return it to their office or a lab.

You may need to repeat cortisol testing twice in one day or multiple times over several days because cortisol levels vary.

How to prepare for a Cortisol test? #

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.

What do Cortisol test results mean? #

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 #

• Effects of large amounts of certain medications.

• Tumor in your pituitary gland that’s producing adrenocorticotropic hormone (ACTH), which stimulates the production of cortisol.

• Tumor in your adrenal gland that’s producing too much cortisol.

• Tumor elsewhere in your body, such as small cell lung cancer.

Low levels of cortisol might indicate #

• Tumor in your pituitary gland tumor that slows ACTH production.

• Underactive or damaged adrenal glands.

• Underactive pituitary gland.