If you pregame before the pregame with a lot of water, you won't get a hangover. Staying routinely conditioned helps out too.
The times I have a hangover, I drink a gatorade, or a full throttle and maybe eat something.
Mods: BPC tune, AEM Meth Injection, BDP downpipe, Wagner intercooler, Bilstien B12 Kit, M3 Control Arms, MB Quartz Kit/Alpine Amp
Best 1/4mi: 12.34s @ 111.88MP/h