The ICG test is recommended as a replacement for the nowadays rarely performed BSP test. ICG has less side effects, and it has a greater range of use. Extrahepatic influences are of little importance. Disadvantages are the greater cost and extra equipment required, the labile nature of the dye solution and the calculation procedure. Reference ("normal") values of the clearance coefficient are 0.044 to 0.131 min-1 and those for the half life 5.2 to 11.2 min. The test is suitable for information about the secretion of the whole liver and the state of its circulation.