What is a bilirubin blood test? 

A bilirubin blood test measures the levels of bilirubin in your blood. Bilirubin is a yellowish substance made during the body’s normal process of breaking down red blood cells. Bilirubin is found in bile, a fluid in your liver that helps you digest food.  

If your liver is healthy, it will remove most of the bilirubin from your body. If your liver is damaged, bilirubin can leak out of your liver and into your blood. When too much bilirubin gets into the bloodstream, it can cause jaundice, a condition that causes your skin and eyes to turn yellow. Signs of jaundice, along with a bilirubin blood test, can help your health care provider find out if you have liver disease. 

This test may also be referred to as total serum bilirubin or TSB. 

What is it used for? 

A bilirubin blood test is used to check the health of your liver. The test is also commonly used to help diagnose newborn jaundice. Many healthy babies get jaundice because their livers aren’t mature enough to get rid of enough bilirubin. Newborn jaundice is usually harmless and clears up within a few weeks. But in some cases, high bilirubin levels can lead to brain damage, so infants are often tested as a precaution. 

Why do I need a bilirubin blood test? 

Your health care provider may order a bilirubin blood test: 

• If you have symptoms such as jaundice, dark urine, or stomach pain. These could indicate hepatitis, cirrhosis, or other liver diseases 
• To find out if there is a blockage in the structures that carry bile from your liver 
• To monitor existing liver disease or disorder 
• To diagnose disorders related to problems with red blood cell production. High bilirubin levels in the bloodstream may be a sign of gallbladder disease and a condition called hemolytic anemia 

What happens during a bilirubin 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 don’t need any special preparations for a bilirubin blood test. If your health care provider has also ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your health care provider will let you know if there are any special instructions to follow. 

Are there any risks to the 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? 

Normal results can vary, but high bilirubin levels can mean your liver isn’t working right. However, abnormal results don’t always indicate a medical condition needing treatment. Higher than normal bilirubin levels can also be caused by medications, certain foods, or strenuous exercise. To learn what your results mean, talk to your health care provider or Care Team. 

Is there anything else I need to know about a bilirubin blood test? 

A bilirubin blood test is only one measure of your liver health. If your health care provider thinks you might have liver disease or a red blood cell disorder, other tests may be recommended. These include liver function tests, a group of tests that measure different substances in your blood, and tests for certain proteins made in the liver. In addition, your health care provider may recommend urine tests, an ultrasound, or a biopsy to get a sample of tissue from your liver to examine. 

Source: MedlinePlus, National Library of Medicine