The hangover is the most easily preventable headache, but arguably the most fun to help produce. Excessive alcohol consumption often leads to what feels like brain death the next day. Unfortunately, there's no magical number of drinks that you have to consume to get the dreaded hangover. Much like our decision-making process after we've already had a few, there's a bit of randomness to it -- a single wine spritzer may crush one person's head, while repeated keg stands bounce off the brain of another.
Nausea, shakiness, bloodshot eyes and deep regret over the previous night's karaoke performance usually accompany hangover headaches. Nobody's sure what exactly causes hangovers, but many factors are at play: dehydration, blood-vessel expansion, immune-system response, falling blood-sugar levels and substances called congeners -- toxic chemicals that are a byproduct of fermentation and that appear more often in dark liquors than in clear liquors.
While nearly everyone who's experienced a hangover has his or her own unique attempts at a cure, common treatments include sleep, fluids, darkness, snacks and OTC pain relievers. But take note that consuming aspirin and alcohol simultaneously increases the risk of damage to your intestinal lining and may damage your liver.
Put on your helmet, because headache worlds collide in the next section.