The aminotransferases are usually not greatly elevated in obstruc- tive jaundice. One notable exception occurs during the acute phase of biliary obstruction caused by the passage of a gallstone into the com- mon bile duct. In this setting, the aminotransferases can briefly be in the 1000–2000 IU/L range. However, aminotransferase levels decrease quickly, and the biochemical tests rapidly evolve into those typical of cholestasis.