Both of my parents are physicians, and both have worked in emergency rooms at some point in their careers. One thing they've taught me is to be cautious about taking too much Tylenol.

At the right dose, Tylenol may well be the safest pain medication we have, even compared to Advil, which can occasionally cause problems if taken regularly over a lifetime. However, the gap between a useful dose of Tylenol, and the amount of Tylenol which will kill you, is relatively small compared to similar medicines.

My parents say they've watched a lot of people die in the hospital from Tylenol overdoses. There is an antidote, but only if you get it in time.