What are catecholamine tests?

Catecholamines are a group of hormones made by your adrenal glands, two small glands located above your kidneys. Hormones act as chemical messengers in your bloodstream. They carry information that controls the actions of certain cells or organs.  The main types of catecholamines are dopamine, norepinephrine, and epinephrine. Epinephrine is also known as adrenaline.

These hormones are released into the body in response to physical or emotional stress. This response is sometimes referred to as your body's "fight or flight" response to stress. When catecholamines enter your bloodstream:

• Your blood flow increases to your muscles and brain
• You become more alert
• Your heart rate and blood pressure increase
• You get more adrenaline for energy

Catecholamine tests measure the amount of catecholamines in your urine or blood. Usually, these hormone levels are low and increase during and just after a stressful situation. Then these levels return to a normal level once the stressful situation has ended. Blood or urine levels of dopamine, norepinephrine, and/or epinephrine that stay higher than normal can be a sign of certain rare tumors.

Other names: dopamine, norepinephrine, epinephrine tests, free catecholamines, fractionated catecholamines

What are they used for?

Catecholamine tests are most often used to diagnose or rule out certain types of rare tumors, including:

• Pheochromocytoma, a tumor of the adrenal glands. This type of tumor is usually benign (not cancerous). But it can be fatal if left untreated.
• Neuroblastoma, a cancerous tumor that develops from nerve tissue. It mostly affects infants and children.
• Paraganglioma, a type of tumor that forms near the adrenal glands and can cause high blood pressure. This type of tumor is sometimes cancerous, but it usually grows very slowly.

The tests may also be used to see if treatments for these tumors are working.

Why do I need a catecholamine test?

You or your child may need this test if you have symptoms of a tumor that affects catecholamine levels. Symptoms in adults include:

• High blood pressure, especially if it isn't getting better with treatment
• Severe headaches
• Sweating
• Rapid heartbeat
• Anxiety
• Tingling in your arms and legs

Symptoms in children include:

• Bone pain or tenderness
• An abnormal lump in the abdomen
• Weight loss for no known reason
• Uncontrolled eye movements

Treatment of these rare tumors may help to control or reduce your high blood pressure. But if the tumors are not treated, your symptoms may get worse. The tumors may continue to grow and could cause more severe health problems.

What happens during a catecholamine test?

A catecholamine test may be done in urine or blood. Urine testing is done more often because catecholamine blood levels can change quickly and may also be affected by the stress of testing.

But blood testing can be useful in helping to diagnose a pheochromocytoma tumor. This type of tumor may make certain substances and release them into your bloodstream. These substances may include extra catecholamines.

For a catecholamine urine test, your health care provider will ask you to collect all your urine during a 24-hour period. This is called a 24-hour urine sample test. For 24-hour urine sample test, you'll be given a special container to collect your urine and instructions on how to collect and store your samples. Your provider will tell you what time to start. The test generally includes the following steps:

• To begin, urinate in the toilet as usual. Do not collect this urine. Write down the time you urinated.
• For the next 24 hours, collect all your urine in the container.
• During the collection period, store the urine container in a refrigerator or cooler with ice.
• 24 hours after starting the test, try to urinate if you can. This is the last urine collection for the test.
• Return the container with your urine to your provider's office or the laboratory as instructed.

During a blood test, a health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for the test?

You may be asked to avoid certain foods for two to three days before the test. These could include:

• Caffeinated foods and drinks, such as coffee, tea, energy drinks, and chocolate
• Alcohol and tobacco
• Bananas
• Citrus fruits
• Foods that contain vanilla

You may also be asked to avoid stress and vigorous exercise before your test, as these can affect catecholamine levels. Certain medicines may also affect levels. Be sure to tell your provider about all the medicines you are taking. But don't stop taking any medicines unless your provider tells you to.

If you are having a blood test, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions to follow.

Are there any risks to the test?

There is no risk to having a urine test.

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

What do the results mean?

If your results show high levels of catecholamines in your urine or blood, it may be a sign of a pheochromocytoma, neuroblastoma, or paraganglioma tumor. If you are being treated for one of these tumors, high levels may mean your treatment is not working.

High levels of these hormones don't always mean you have a tumor. Your levels of dopamine, norepinephrine, and/or epinephrine can be affected by stress, vigorous exercise, caffeine, smoking, and alcohol.

To understand the results of your catecholamine test, your provider may consider your symptoms, medical history, and the results of other tests.

If you have questions about your results or your child's results, talk to your provider.

Is there anything else I need to know about catecholamine tests?

These tests can help diagnose certain tumors, but they can't tell whether the tumor is cancerous. Most tumors are not. If your results showed high levels of these hormones, your provider will probably order more tests. These include imaging tests such as a CT scan or an MRI, which can help your provider get more information about a suspected tumor.

Learn more about laboratory tests, reference ranges, and understanding results.