See if you can get some camprel (acamprosate) prescribed for him. Especially if he has some interest in quitting booze.
It's basically the safest booze-quitting medication out there, and has no interactions with anything. He can take it and still drink if he wants, although that's defeating the purpose.
If you get an appointment with a psychiatrist (maybe even a doctor) they may have some sample books filled with camprel tablets. Your boyfriend can try it.
The way it works is, you lose the physical urge to drink. It's as if you could take or leave alcohol.
I tried the pills a few times, and it seems to work.
Lemme know!