This Is Why Drinking Alcohol Gives You Diarrhea - By Suzannah Weiss

After a night of drinking, you might not just wake up with a pounding head and a dry mouth. You might find yourself greeting the day in a slightly different way: chained to the toilet.

If you notice unusual pooping patterns after a night of drinking, it's not your imagination.

The effects of alcohol actually create the perfect storm for diarrhea, says gastroenterologist Andrew Black, M.D.

And there are actually many issues at play here. First of all, alcohol can irritate the lining of your intestines, which not only makes them leak fluid into your gut, but also makes their muscle contractions stronger and more frequent. Those are the same contractions that trigger your urge to go, as they move waste through your system.

If these contractions are on overdrive, they might be pushing your poop out before your intestines have the chance to absorb extra water from your waste. The result? You might be pooping out loose, watery stool before it's well-formed. (Here's why drinking coffee makes you poop.)

On top of becoming leaky and overly active, your irritated intestines may have trouble doing their usual job of absorbing fluid when you’re drunk, leaving your poop in its pre-dehydrated state.

“Thus there is a triple whammy—too much fluid exiting, too little being absorbed, and the gut working overtime to push things out the door,” Dr. Black explains.

The source of your runs may extend beyond intestinal irritation, too. Alcohol can kill off the good bacteria in your gut, which could alter the balance of the bugs, leading to a higher concentration of the bad bacteria. That's a problem, since too many of the bad guys can further impair your intestines' ability to absorb water. What's more, too much alcohol can also stimulate the production of acid in your stomach—yet another fluid mixed in with the stool.

It's also possible that it's not only the alcohol content in your gut that's causing your prolific pooping: The other components of the drink may play a part, too, says Dr. Black. For instance, if you have gluten sensitivity or problems absorbing carbohydrates, drinks like beer or sugary cocktails may further irritate your gut, making the symptoms even worse. Some people may also experience gut distress with artificial sweeteners, which can be found in sugar-free mixers. (Get the latest health, weight loss, fitness, and sex intel delivered straight to your inbox. Sign up for our "Daily Dose" newsletter.)

If you want to avoid the drinking diarrhea, first start by keeping your imbibing in check: Stick to the daily recommended limit of no more than two drinks a day. The more you drink, the worse the diarrhea, says Dr. Black.

Then make sure to alternate each drink with plain water, too. Staying hydrated can help dilute the alcohol in your system, making its effects less pronounced. And if you notice having digestive distress with high-carb drinks, Dr. Black recommends switching to something low-sugar like a single malt instead.