Percocet contains acetominophen, which can be very toxic to the liver, particularly in doses greater than 4 grams per day (the amount in 8 of the extra-strength
percocet tablets).
Taking more than that can eventually cause cirrhosis of the liver, a chronic, potentially fatal illness.
The greater effects of percocet, however, are on the mind; addiction changes a person, making him emotionally distant, irritable, and basically 'checked out' of relationships.