TARCEVA 150MG TABLET should be taken in a dose as recommended by the doctor. You should continue to take it as long as your doctor advises for it. The duration of treatment varies according to your need and response to treatment. Your doctor may advice for regular monitoring of liver function while your taking this medicine. It is advisable to avoid smoking while taking TARCEVA 150MG TABLET as it makes the medicine ineffective and requires dose adjustment.