He needs more help than you can offer I'm afraid to say. Having had friends with serisous drugs problems you should do whatever you can to get him into a rehab clinic. Talk to as many people as you can that care about him. Without that network of support and a desire to quit I'm sorry to say he won't make it. The best advice I can offer you is to call an area rehab clinic and talk to someone there about his problem.

I am in no way a professional and I would suggest you seek the advice of one.