Baclofen is a drug which has been used for a long time for neurological problems, and has a good record for safety. However, it's no longer under patent, and there's no one who's interested in putting up the $500,000 which it would cost to test it for helping with addictions. This surprises me-- admittedly, the companies that make it don't want to do any favors for their competitors, but why isn't some government or charity interested in this?
Part of what's interesting about the book is the portrayal of prejudice against alcoholics (probably against addicts in general)-- the author mentions that he got significantly worse hospital care for alcoholism than for other problems.
Also, the craving for alcohol cuts into quality of life in a big way (whether the person drinks or not) but is generally not considered to be a problem worth treating.
He'd been saying for years that he drank because of his anxiety. People would tell him that if he stopped drinking, his anxiety would go away. This simply wasn't true, and they had no reason to think it was true.