Doctors reveal how alcohol causes ‘booze butt’ ahead of New Year’s

A night of drinking doesn’t just come with a headache or dry mouth.

It can also mean urgent trips to the restroom.

The phenomenon — dubbed “booze butt” by Men’s Health — is real.

Alcohol can irritate the digestive tract, alter gut bacteria and interfere with how the intestines absorb water, doctors said. 

“Alcohol itself can cause loose stools due to several mechanisms,” Dr. Leybelis Padilla, a San Diego-based gastroenterologist and lifestyle medicine physician, told Fox News Digital.

It can also inhibit fluid absorption in the intestines and speed digestion, she said.

“When the intestines move too quickly, there’s less time for water to be absorbed,” Padilla said. “That can result in loose or watery stools.”

Alcohol hits every “layer” of the gut as it moves through the digestive tract, according to Dr. Jason Korenblit, a Florida-based gastroenterologist.

It can worsen heartburn, increase stomach acid and weaken the gut barrier, Korenblit told Fox News Digital.

“Alcohol can also make the gut ‘leakier,’” he added. “Alcohol and its byproducts can weaken the tight ‘seals’ between intestinal cells, allowing bacterial toxins to cross the gut barrier and promote inflammation.”

But not everyone experiences digestive issues after drinking, and doctors say several factors determine who is more susceptible.

Dose and speed matter, Korenblit said. “More drinks in less time equals more irritation and more leaky-gut or irritable bowel effects,” he said.

Underlying digestive conditions such as acid reflux, irritable bowel syndrome, inflammatory bowel disease, celiac disease or chronic gastritis can increase sensitivity.

No alcoholic beverage is completely “safe” for the gut. 

Genetics can play a role as well, Padilla noted. 

“Certain genetic variants can make someone more susceptible to alcohol’s effects,” she said.

While no alcoholic beverage is completely “safe” for the gut, doctors say some drinks are more likely to trigger symptoms than others. 

Common offenders include mixed drinks, wine and beer, as they often contain sugars or sugar alcohols that can worsen diarrhea, Padilla said.

“Some of these sugars include fructose, lactose, mannitol, xylitol and erythritol,” she said.

Beer and sparkling drinks can worsen bloating and heartburn due to carbonation, while high-proof shots can cause irritation, Korenblit said. 

Creamy drinks may be problematic for people who are lactose-sensitive. “Sugar also makes drinks easier to over-consume, which increases total alcohol dose,” he noted.

Lower-alcohol, lower-sugar drinks consumed slowly are generally easier on digestion, both doctors agreed.

To lessen the risk of digestive issues from drinking, doctors also recommend eating before drinking, limiting intake to two drinks a day, staying hydrated and not mixing alcohol with caffeine, which can further stimulate the gut. (Many doctors note it’s best to abstain from alcohol completely.) 

They also recommend caution if taking other medications. 

“Mixing alcohol with NSAIDs — ibuprofen, naproxen, aspirin — increases GI bleeding risk and can worsen irritation,” Korenblit said.

Health officials note that other commonly used medications, including certain antidepressants such as selective serotonin reuptake inhibitors (SSRIs), can also worsen diarrhea or increase gastrointestinal irritation when combined with alcohol.

While these tips can mitigate symptoms, there is no surefire way to prevent them altogether. “Hydration helps — but mostly by preventing dehydration, not by magically stopping diarrhea,” Korenblit said. 

If symptoms linger, he recommends sticking to easy-to-digest foods such as oatmeal and bananas. 

Soluble fiber, broth and soups can help firm up stools and replace lost fluids. Fermented foods like yogurt or kefir may also help for those who tolerate dairy.

Greasy foods, spicy meals and more alcohol — including “hair of the dog” — are likely to worsen diarrhea, doctors agree.

For most people, however, the gut microbiome is resilient, Korenblit added.

“In studies of heavy drinking, microbiome diversity and related changes improved with abstinence and a healthier diet, suggesting recovery is possible,” he said. 

“Stopping or cutting back is one of the best ways to let the system rebound.”

If diarrhea after drinking lasts more than 48 to 72 hours or is accompanied by blood, black or tarry stools, severe or worsening pain, fever, vomiting, dizziness or signs of dehydration, people should seek medical attention, according to the American College of Gastroenterology.