Elevated liver enzymes often are a sign of inflamed or damaged cells in the liver. Inflamed or injured liver cells leak higher levels of certain chemicals into the bloodstream. These chemicals include liver enzymes that may appear higher than usual on blood tests.

The most common elevated liver enzymes are:

• Alanine transaminase (ALT).
• Aspartate transaminase (AST).
• Alkaline phosphatase (ALP).
• Gamma-glutamyl transpeptidase (GGT).

Many diseases, medications and conditions can cause elevated liver enzymes. Your healthcare team will review your medicines and symptoms and sometimes prescribe other tests and procedures to find the cause.

Common causes of elevated liver enzymes include:

• Nonprescription pain medicines, particularly acetaminophen (Tylenol, others).
• Certain prescription medicines, including statins, which are used to control cholesterol.
• Drinking alcohol.
• Heart failure
• Hepatitis A
• Hepatitis B
• Hepatitis C
• Nonalcoholic fatty liver disease
• Obesity

Other possible causes of elevated liver enzymes include:

• Alcoholic hepatitis (This is severe liver damage caused by drinking too much alcohol.)
• Autoimmune hepatitis (This is liver damage caused by an autoimmune disorder.)
• Celiac disease (This is damage to the small intestine caused by gluten.)
• Cytomegalovirus (CMV) infection
• Epstein-Barr virus infection.
• Hemochromatosis (This condition may happen if there is too much iron stored in the body.)
• Liver cancer
• Mononucleosis
• Polymyositis (This condition inflames the body's tissues causing muscle weakness.)
• Sepsis
• Thyroid disorders.
• Toxic hepatitis (This is liver damage caused by medicines, drugs or toxins.)
• Wilson's disease (This condition may happen if there is too much copper stored in the body.)

Pregnancy rarely leads to liver diseases that raise liver enzymes.

If a blood test shows that you have elevated liver enzymes, ask your healthcare team what the results might mean. You may have other tests and procedures to find the cause of the elevated liver enzymes.