Bilirubin, a byproduct of liver function, can cause health problems at abnormal levels. It is created during breakdown of old or red blood cells, and gives both bile and feces their yellow-brown color. Bilirubin levels can be measured either in the bloodstream or directly from the liver. Healthy levels in the bloodstream range from .20 milligrams per decileter (mg/dL) to 1.50 mg/dL. In the liver, healthy levels average between .00 and .03 mg/dL. These levels can be measured during liver function tests.
Jaundice can be a sign of abnormally high bilirubin levels. When too much bilirubin builds up in the blood, it can cause yellowing of the skin and the whites of the eyes, also called the sclera. Jaundice caused by excessive bilirubin is generally a sign of liver dysfunction. When the liver fails to remove it through excretion, the excess can leak into the blood, discolor the skin, and cause other symptoms, such as brown urine. Many conditions cause this sort of dysfunction — from cirrhosis to anemia, blocked bile ducts, and viral hepatitis.
People suffering from high bilirubin can also experience nausea, which may or may not lead to vomiting. Fatigue, when paired with other symptoms, may also be a sign of excess bilirubin in the blood or liver. High bilirubin levels are usually only one symptom of a liver disorder, and associated symptoms may vary depending on the disease or condition causing liver dysfunction.
In infants, high bilirubin levels can be fatal. Hyperbilirubinemia, the condition of excess bilirubin in infants, can cause brain damage and related problems, like permanent deafness, muscle dysfunction, or death. Infants with jaundice are often treated with blood transfusions or light therapy to minimize their risk and reduce excess bilirubin. Tests for bilirubin over 25 mg/dL can be performed via a heel stick, which is a blood sample taken from the foot's heel.
In adults, the first step to maintaining healthy bilirubin levels is maintaining a healthy liver. This means following a properly balanced diet. Also, avoid excessive intake of anything that can cause liver toxicity. This can include alcohol, tobacco smoke, and drugs that affect liver function — including some standard, over-the-counter, pharmaceuticals.
Regular liver function tests can also identify any conditions that may require treatment. Early identification of liver dysfunction can prevent long-term problems that could lead to severe liver damage and excess bilirubin. For already-damaged livers, enzyme therapy can help boost liver function and reduce toxic bilirubin levels.