My friend drank way too much on New Year's Eve and was sick for an entire. I--err, she has never had a hangover like that before and she didn't even drink *that* much. Can we safely blame the altitude? It was her first binge drinking session in Colorado.
She is probably suffering from altitude sickness in addition to the hang over. Symptoms are pretty common. Both are caused by dehydration. Headache, fatigue, stomach illness, dizziness, and sleep disturbance are all symptoms of Altitude Sickness.
You can increase her water in take, aspirin and get her some oxygen. It should be gone in a day or 2 much like the hang over. Too late for preventative drugs.
Just about everything is worse at high altitude. If you're not accustomed to the lower barometric pressure and possibly less oxygen content in the air, you can feel a lot worse for a lot longer. It's not worse for you than a hangover at sea level, it just feels that way.
Altitude acclimatisation is essential. Your 'friend' should have built up to this epic binge by drinking progressively greater amounts over the Advent period.
(And posting a vlog about the project on youtube. Heh.)