B1AS tests the hypothesis that increased vitamin B1 (thiamine) intake can repair brain systems damaged by alcohol and help people with alcohol problems control their alcohol use. A strong, man-made form of thiamine (Benfotiamine) is used to increase blood thiamine to much higher levels than can be achieved using normal vitamin supplements. Drinking patterns are examined over 6 months of continued supplement use. Men and women with a recent history of alcohol problems are eligible to participate.