What do the results of an aspartate aminotransferase level test mean?

An aspartate aminotransferase (AST) test measures the amount of this enzyme in the blood. Results are usually available within 12 hours.

The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what’s normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.

Aspartate aminotransferase (AST) 1

• Males: 14–20 units per liter (U/L) or 0.23–0.33 microkats per liter (mckat/L)
• Females: 10–36 U/L or 0.17–0.60 mckat/L

High Values

High levels of AST may be caused by:

• Liver damage from conditions such as hepatitis or cirrhosis.
• Decay of a large tumor (necrosis).
• A heart attack or heart failure.
• Many medicines, such as statins, antibiotics, chemotherapy, aspirin, narcotics, and barbiturates.
• Having taken high doses of vitamin A.Kidney or lung damage.
• Mononucleosis.
• Some types of cancer.