All content on Lab Tests Online has been reviewed and approved by our Editorial Review Board.
The Test Sample
What is being tested?
A liver panel is a group of tests that are performed together to detect, evaluate, and monitor liver disease or damage. The liver is one of the largest organs in the body and is located in the upper right-hand part of the abdomen and behind the lower ribs. The liver metabolizes and detoxifies drugs and substances that are harmful to the body. It produces blood clotting factors, proteins, and enzymes, helps maintain hormone balances, and stores vitamins and minerals. Bile, a fluid produced by the liver, is transported through ducts directly to the small intestine to help digest fats or to the gallbladder to be stored and concentrated for later use.
A variety of diseases and infections can cause acute or chronic damage to the liver, causing inflammation (hepatitis), scarring (cirrhosis), bile duct obstructions, liver tumors, and liver dysfunction. Alcohol, drugs, some herbal supplements, and toxins can also pose a threat. A significant amount of liver damage may be present before symptoms such as jaundice, dark urine, light-colored stools, itching (pruritus), nausea, fatigue, diarrhea, and unexplained weight loss or gain emerge. Early detection is essential in order to minimize damage and preserve liver function.
The liver panel measures enzymes, proteins, and substances that are produced, processed or eliminated by the liver and are affected by liver injury. Some are released by damaged liver cells and some reflect a decrease in the liver's ability to perform one or more of its functions. When performed together, these tests give a healthcare practitioner a snapshot of the health of a person's liver, an indication of the potential severity of any liver injury, change in liver status over time, and a starting place for further diagnostic testing.
For additional details on the tests included in the panel, see The Test tab.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm. For infants, blood may be drawn by puncturing the heel with a lancet.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
Some of the tests that may be included in the panel may require fasting overnight with only water permitted. Follow any instructions provided. Inform the healthcare practitioner about all prescription and over-the-counter medications, herbal medications, vitamins and supplements being taken.