My boyfriend (18, 6 0, 150 lbs) took five extra-strength Tylenol pills 3.5 hours ago. After a half hour, he blacked out for an hour. Once he woke up, he said that the headache he was trying to treat had gotten worse, and he was nauseous and having bad stomach pain. I called Poison Control, and they said to go to the ER immediately. However, he and his parents refuse to go, they think that he ll be fine. Is there anything I can do?