What Happens When you Mix Tylenol and Alcohol
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If you enjoy a cocktail, here's another reason not to take Tylenol: A new study of more than 10,000 adults found that light and moderate drinkers who also take acetaminophen painkillers more than double their risk of kidney disease.

Doctors have known for some time that excessive boozing or acetaminophen use can cause liver damage. But your liver is not alone; this study found that combining alcohol and acetaminophen can also damage your kidneys. The risk is high: Even when study participants had only small doses of acetaminophen, kidney disease skyrocketed on average 123 percent.

Why is the combination so dangerous? Lead study author Harrison Ndetan says that acetaminophen is primarily excreted by the kidneys and that alcohol hinders the organs' ability to process the painkiller by inhibiting a particular protein. On top of that, dehydration, a common side effect of alcohol, can hurt kidney function, while acetaminophen can disrupt blood flow in and out of the organs. Basically, combine the two drugs, and you create a mess of problems for the kidneys.

Ndetan's team didn't look into how closely together the participants who had kidney disease used alcohol and acetaminophen – only that they drank up to two drinks per day and took the painkiller occasionally. Having just a few drinks or popping the occasional Tylenol doesn't pose a problem, they say. But since it's now known that alcohol and acetaminophen, when one person ingests both, can harm the liver and kidney, you may want to avoid acetaminophen altogether – if you prefer your cocktails. In other words, don't go there the next time you're nursing a hangover.