He could have killed himself (spoilers)

That part where he goes over every detail to make himself look like he was dying of AIDS made me wonder how he kept from really dying when he took all those pills so he'd throw himself into a coma. How was he to know that he was going to go into a coma and even if he did start flat lining or something then there was still a great chance of them losing him because they didn't know that he ingested anything