Why do I get diarrhea after drinking alcohol?

Morning diarrhea after drinking is alcohol working on the gut from several directions at once: it speeds up intestinal contractions so contents move through before water gets absorbed, it irritates and inflames the gut lining directly, and it throws off gut bacteria. Drinks make it better or worse: beer and sugary cocktails are the worst offenders - sugar and fermentation byproducts draw water into the bowel - while clear spirits in modest amounts are gentler. People with IBS feel this most, since their guts are already reactive. Managing the morning after: fluids with electrolytes, since diarrhea plus dehydration compound; plain food - the usual bland suspects; and skipping caffeine, which adds its own gut-speeding effect. It typically resolves within a day. Prevention is dose and choice: less, slower, with food, and fewer sugary or carbonated mixers. Patterns that mean more than a hangover gut: diarrhea with blood or mucus, diarrhea lasting more than a couple of days after a single night, diarrhea that follows even small amounts of alcohol reliably, or ongoing changes between drinking occasions - those deserve a provider conversation about the gut itself, since regular heavy drinking can inflame the pancreas and liver too, and persistent diarrhea has its own differential. Severe abdominal pain with vomiting after heavy drinking - especially pain boring through to the back - is a pancreatitis pattern and a same-day assessment. Pymander is a free AI doctor, 24/7 by text. Describe the pattern and what you drank, and it can help you read it.