To detect liver damage or disease
Monitor liver conditions such as hepatitis or fatty liver
Evaluate effects of medications that may harm the liver
Screen for asymptomatic liver disease in at-risk individuals
Men: 10–40 U/L
Women: 7–35 U/L
Children: 7–55 U/L
(Normal ranges can vary slightly between labs.)
Normal ALT: Suggests healthy liver function.
Mild Elevation (40–80 U/L): Could indicate non-serious or early-stage liver damage (e.g., fatty liver).
Significant Elevation (>100 U/L): Suggests acute or severe liver injury (e.g., hepatitis, drug toxicity).
Severe Elevation (>500 U/L): Often indicates acute liver failure, infection, or severe injury.
Specimen: Blood serum.
Collection Method: A small blood sample drawn from a vein, typically in the arm.
Preparation: Fasting may be required based on additional tests ordered alongside ALT.