Diarrhea: Causes, Fast Relief & When to Seek Help

Diarrhea is annoying and can be serious if it dehydrates you. Most cases clear up in a day or two, but quick action helps you feel better and avoids complications. Read on for practical steps you can use at home, what medicines help (and when they don't), and clear warning signs that mean you should get medical help.

Quick at-home fixes

Start with fluids. Sip oral rehydration solutions (ORS) or make one at home: 1 liter of clean water, about 6 level teaspoons sugar and 1/2 teaspoon salt. Keep drinking small amounts often—sports drinks help a little but they have too much sugar for some cases.

Watch what you eat. For a short time stick to bland, easy foods: toast, bananas, rice, boiled potatoes, plain pasta. Avoid dairy (especially if you feel worse after milk), greasy food, spicy dishes, and alcohol until things settle.

Over-the-counter options: loperamide (Imodium) can cut stool frequency for adults with non-bloody, low-fever diarrhea. Bismuth subsalicylate (Pepto-Bismol) helps traveler’s diarrhea and mild stomach upset. Don’t use these if you have high fever, bloody stools, or severe belly pain—those signs point to an infection where slowing the gut could be harmful.

Probiotics like Saccharomyces boulardii or Lactobacillus strains may shorten symptoms for some people. They’re safe for many adults, but check with your pharmacist if you’re seriously ill, pregnant, or immunocompromised.

When to see a doctor

Seek urgent care if you have any of these: severe belly pain, fever over 38.5°C (101.3°F), blood or black stools, signs of dehydration (very dry mouth, very little urine, dizziness), or diarrhea that lasts longer than 48–72 hours. Babies, older adults, and people with weak immune systems should see a clinician sooner.

Antibiotics are sometimes needed for bacterial causes, but they must be chosen carefully. Some antibiotics cause diarrhea themselves or trigger C. difficile, a serious infection. If you recently took antibiotics and have worsening diarrhea or blood in stool, tell your doctor right away.

Remember meds can both cause and be affected by diarrhea. Drugs like metformin, magnesium supplements, some blood pressure pills, and certain antidepressants can loosen stools. Fast stool transit reduces absorption of oral meds and can change blood levels. If diarrhea is linked to a prescription drug, talk to your prescriber or pharmacist—there are often alternatives or dosing changes that help.

Travel tip: avoid tap water, raw salads, and street ice in high-risk areas. Use bottled water for brushing teeth and choose cooked hot food. If you get traveler’s diarrhea, focus on fluids and short-term remedies; see care if symptoms are severe or prolonged.

If you’re unsure, calling your doctor or a local pharmacist is a smart move. They can help you decide whether home care is fine or you need tests, antibiotics, or other treatment. Quick action and the right choices cut risk and get you back to normal faster.