Life may get a little more painful. A federal advisory panel voted on Tuesday to ban Percocet and Vicodin, two of the world's most popular prescription painkillers, because of their harmful effects on the liver. The ingredient in question is acetaminophen--found in Tylenol, Excedrin and other over-the-counter drugs--which, in high doses, is a leading cause of liver damage. In 2005, Americans bought 28 billion doses of products containing the ingredient, and more than 400 people die and 42,000 are hospitalized every year in the U.S. from overdoses. The panel also voted to reduce the amount of acetaminophen in over-the-counter drugs and lower the recommended daily dosage. While the F.D.A. isn't required to heed its recommendations, they usually follow advisory panels' advice.