Eventually the hangovers stopped.

(Vatchi): Sotto, I don't think Jim realizes that he was still drunk before his first drink that day. He was already delirious, fading in and out of his blackout like house lights flickering in a thunderstorm.The delirium tremens would come later. Years later. The level of alcohol in his bloodstream never got low enough for serious shakes to start. He maintained. Maintenance drinking. For years, apparently. "What is a life when the blackout precedes the first drink?"

from All Drinking Aside:The Destruction, Deconstruction and Reconstruction of An Alcoholic Animal (Rough Draft, Chapter 5)