Its not gonna kill you. That being said, it definitely won't help anything and it's effects on your routine are probably more detrimental than that of your body.
You end up losing sleep, being tired the next day, not eating the same, skipping the gym if you're hungover.
I drank on New Years eve.. 5 or 6 beers -- had some sesapure with it, followed the drinking with 2 bottles of water and then 2 more when i woke up. I felt fine in the morning. Just had to piss a lot.