Comment by simplicio

Extra strength tylenol is 500mg a tablet, so 20 pills. Think most of the accidental ODs are due to people not realizing its included in other cold meds, and also being loopy from whatever illness they're trying to manage, and so end up forgetting when they last took the meds.

Its also a pretty popular choice for people trying to kill themselves, though, so I suspect a non-trival chunk of ODs in the statistics given in the article were intentional.