What happened to Juice's body before he died?

Six months ago I started to get more into his discography, and as I became more and more a fan of his music, I started to follow Juice fan sites. And I noticed that they said he was bleeding from the stomach days before he died, and he had only days left before a greater tragedy. Why was that with him? What was wrong with him? I know about your addiction, but how is it connected? I'm sorry if this sounds stupid, but I really don't understand