What it is: Liver function tests are a group of blood tests — typically ALT, AST, ALP, GGT, bilirubin, albumin, and total protein — run together to assess how well the liver is working.
Why it's ordered: Ordered as routine screening, to evaluate symptoms like jaundice, abdominal pain, or fatigue, or to monitor known liver disease or medications that can affect the liver.
What it detects: Each component reflects a different aspect of liver health: enzymes (ALT, AST, ALP, GGT) signal cell damage or bile duct issues, while bilirubin, albumin, and total protein reflect how well the liver is processing and producing key substances.
Collection & prep: A standard blood draw from a vein in the arm. No special preparation is typically required, though fasting may be requested if paired with other tests.
Results:
Elevated enzymes (ALT/AST) – suggest liver cell damage; the pattern (which enzyme is higher) can hint at the cause, such as alcohol-related injury
Elevated ALP/GGT – suggest bile duct involvement
Abnormal bilirubin, albumin, or total protein – suggest impaired liver processing or synthesis
Possible complications of liver dysfunction: Liver function tests can flag a problem but usually can't pinpoint the exact disease; abnormal results often lead to imaging, viral hepatitis testing, or a liver biopsy to reach a final diagnosis.
Statements made in the Clinical Manual have not been evaluated by the FDA. The products mentioned are not intended to diagnose, treat, cure or prevent any disease.
