6 Surprising Things That Can Cause Killer Hangovers

You might think taking an OTC pain reliever on the night of a party is a smooth move—like it’s an insurance policy against that next-day headache. But “acetaminophen can cause severe damage to your liver when consumed with alcohol,” says Dr. Schaefer. “Your liver has to process both the pain reliever and the alcohol, so the process takes longer.” In other words, you're not only putting your body in danger—but you’ll also be feeling the effects of all that alcohol well into the next morning.