What to do if I overdose on paracetamol, what should I do also what harm can it do to me?

Get to an ER NOW! Acetaminophen, brand name Tylenol, (acetaminophen) while safe at doses recommended, in overdose can saturate the usual route the body uses to break it down and the excess spills to another elimination system that converts it to a metabolite that will cause complete liver failure. There are no symptoms until a week later when the only cure is liver transplant. 6 grams, 12 extra strength Tylenols (acetaminophen) is all it takes.