If you've been friends for a long time, it'll be kind of hard. You have two choices.
Either sort of ghost him (which is really rude) and tell him you're busy all the time. Don't lie. But just say that you can't hang out because you have things to do.
The second option, and I've done this before, is the next time he calls, swallow your pride, and tell him straightforward, but kindly that you don't like being around him when he drinks, that he becomes really crass and unpleasant, and you're worried about his health.
He'll most likely (for number two) yell at you and tell you to mind your own business. Stay firm, but kind, and he'll hang up on you. You might not hear from him for a year or two. But in that time, other friends may say the same thing, and he'll have to look at his life and make some changes.
It's a positive thing.