I thought the same thing about meth - that is was worse than other drugs. I think it is bad, but more - it is "nortorious"... as is crack... as was heroin. Things go through phases and pill popping is up and coming in the youth, and will become more notorious as time goes on.
Each addict fights the battle himself - each has a fighting chance. You can get your son back... he has to figure it out himself, though. The less enabling we can do, the better.
Taking the phone off the hook was one of my first boundaries - I did it so I could sleep at night...without getting a "come get me" or "come get her out of jail" or "she is in the hospital" calls that I so dreaded. It helped. I slept. That was enough, back then.
Having numbers available for Salvation Army, Teen Challenge (it is available to adults, as well) and other rehabs and NA and AA is a good thing. But don't give them to him until he asks for them. And in the meantime, you might check out a handful of Alanon and Naranon meetings. They really do help.
((hugs))