I stipulated that caffeine will counteract some of the drowsiness caused by alchohol, but I wouldn’t want to count on the stimulant effect to save my butt if I were driving drunk (or after being up for 24 hours for that matter).
The biggest stimulant is the adrenaline that gets flowing if you are ever pulled over after having a few beers.
It happened to me once in 1992. Once you see flashing lights behind you, the adrenaline kick is the equivalent of stabbing someone in the heart with a needle full of adrenaline.
That’s why I don’t understand how anybody ever fails a field sobriety test. You have to be in really bad shape.
At that point I was so petrified and alert I could have walked a straight line on my hands and recited the Chinese alphabet backwards and forwards.