Does anyone know the facts about what abusing pain killers like Oxycontin will do to you?

I know someone who is a bad diabetic & is addicted to Oxycontin & other prescription pain killers. What can it do to his body? He takes them from the moment he wakes up until the moment he goes to bed. He doesn't know that I know & I am going to talk to him about it tonight. Just want to get as many facts as possible before I do. Thanks.

: http://alcoholdrugstreatment.info/does-anyone-know-the-facts-about-what-abusing-pain-killers-like-oxycontin-will-do-to-you