GGT refers to glutamyl transpeptidase, and if GGT is elevated, it often indicates abnormal liver function. However, if other aminotransferase indicators are normal and only glutamyl transpeptidase is high, it is usually common in alcoholic liver disease and drug-related liver injury. Some people with fatty liver may also have elevated transpeptidase alone. In case of biliary obstruction, biliary obstruction is usually caused by gallstones, occupancy, etc. These cause blockage in the bile ducts inside and outside the liver, and high GGT may also appear when obstruction occurs. If the GGT is simply high, further examination should be done to determine the cause based on these conditions, and then further treatment should be done.