I have not met anyone yet who has gotten anywhere near the paltry recommendation of 4800mg per day the FDA says we need. Supposedly the lethal amount potassium chloride is 2500mgs per kg of body weight in a very short period of time. If memory serves I recall reading the only death associated to potassium was via a chemical accident and not intentional exposure.....or acute trauma causes destroyed cells to release potassium since 98% of its stored in cells and not serum.
The danger is really too much too fast hitting blood stream so if supplementing its a good idea to take your potassium in multiple doses over the course of the day.