Unconjugated bilirubin (serum/plasma mass concentration)

Why This Test Matters

Bilirubin is a natural byproduct of red blood cell breakdown. Normally, your liver removes it from your blood and sends it to your bile ducts for excretion. If your liver isn’t working properly, bilirubin can build up in your bloodstream, leading to jaundice (yellowing of the skin and eyes). This test helps identify whether your liver or bile ducts may be having trouble processing bilirubin.

Common Causes of Abnormal Results

Elevated levels may suggest conditions like hemolysis (destruction of red blood cells), liver disease, or blockages in the bile ducts. Low levels are less common but might occur with certain genetic disorders or severe liver damage.

What to Expect During the Test

A blood sample is taken from a vein, usually in your arm. You may feel a small pinch, but it’s quick. The sample is sent to a lab for analysis. No special preparation is needed unless instructed otherwise.

Factors That Could Affect Results

Certain medications, infections, or recent blood transfusions can influence bilirubin levels. If you’re taking any medications or have recent health changes, let your doctor know.