Tylenol is usually fine if you stick to the recommended doses. Usually when someone has serious problems with it, they've been taking handfuls at a time (which will completely destroy your liver).
IIRC Tylenol (ie Acetaminophen/Paracetamol) is the leading cause of deaths due to drugs.
Both accidental, because the fatal dose is relatively low compared to the therapeutic dose and because deliberate overdoses are far more likely to be fatal than say sleeping tablets.
