Alcohol makes you poop because it irritates the lining of your intestines and increases gut motility, meaning it speeds up the movement of contents through your digestive system. This irritation reduces the intestines' ability to absorb water properly, leading to softer, sometimes watery stools and an urgent need to go. Additionally, alcohol suppresses vasopressin, a hormone that normally helps your body retain water, which causes increased urination and contributes to dehydration. This dehydration can sometimes cause constipation, but the faster intestinal transit usually results in diarrhea- like symptoms after drinking. Alcohol also disrupts the balance of gut bacteria and causes inflammation, which further affects digestion and stool consistency. These effects together explain why alcohol often leads to loose, urgent bowel movements, often called the "day after drinking shits" (DADS).
