Most diarrhea resolves on its own within a few days, and the single most important thing you can do is stay hydrated. Acute diarrhea typically lasts less than a week. Your main job during that time is replacing lost fluids, eating when you feel ready, and knowing the warning signs that mean something more serious is going on.
Hydration Is the Top Priority
Diarrhea pulls water and electrolytes out of your body fast. Even a mild case can leave you dehydrated if you’re not actively drinking. The signs to watch for: dark urine, urinating less than usual, extreme thirst, dizziness, tiredness, or confusion. If you pinch the skin on the back of your hand and it doesn’t flatten back right away, you’re already significantly dehydrated.
Water alone isn’t enough because you’re also losing sodium, potassium, and other electrolytes. Oral rehydration solutions (sold at most pharmacies) are the gold standard. Broth, diluted juice, and sports drinks can also help. Sip steadily throughout the day rather than gulping large amounts at once, especially if you’re also nauseous. Avoid alcohol and caffeine, which both increase fluid loss.
For infants and young children, dehydration happens faster and is more dangerous. Signs include no wet diapers for three hours, no tears when crying, sunken eyes, a sunken soft spot on the skull, and unusual crankiness or low energy. Infants should continue breastfeeding or formula feeding. Oral rehydration solutions designed for children are widely available and worth keeping at home.
What to Eat (and What to Skip)
The old advice to stick strictly to the BRAT diet (bananas, rice, applesauce, toast) has fallen out of favor. Most experts now say you can return to your normal diet as soon as you feel like eating. Restricting yourself to a handful of bland foods for days can actually slow recovery by depriving your body of the calories, protein, and nutrients it needs to heal. Children with acute diarrhea should eat their usual age-appropriate diet.
That said, a few things are worth avoiding while your gut is irritated. Greasy or high-fat foods speed up intestinal contractions and can make things worse. Sugar alcohols, found in sugar-free gum, candy, and some protein bars, draw extra water into the intestines and worsen loose stools. Dairy bothers some people during a bout of diarrhea because the inflamed gut temporarily produces less of the enzyme that breaks down lactose. If milk seems to make things worse, hold off for a day or two, then try again.
When you do start eating, smaller meals spread throughout the day tend to be easier on the stomach than three large ones. Salty foods like crackers and broth help replace lost sodium.
Over-the-Counter Medications
Two common pharmacy options can reduce the frequency of loose stools. Loperamide (the active ingredient in Imodium) slows the movement of your intestines, giving them more time to absorb water. The standard adult dose is two capsules after the first loose stool, then one capsule after each subsequent loose stool, up to a maximum of eight capsules in 24 hours. Bismuth subsalicylate (Pepto-Bismol) works differently, reducing inflammation and limiting the amount of fluid your intestines secrete.
These medications are fine for garden-variety diarrhea, but you should not use loperamide if you have bloody stools, a high fever, or severe abdominal pain. In those situations, slowing down your gut can actually trap a harmful infection inside. Loperamide is also not recommended for young children without a doctor’s guidance.
Whether Probiotics Help
The evidence on probiotics for diarrhea is mixed and depends on the cause. For antibiotic-associated diarrhea, certain strains show real benefit. In one review of nearly 4,000 children, those given probiotics were significantly less likely to develop diarrhea from antibiotics, with roughly 1 in 10 children benefiting. A separate trial found that the yeast-based probiotic Saccharomyces boulardii cut the average duration of antibiotic-related diarrhea from 9 days down to about 2.
For diarrhea caused by a stomach bug, the picture is less clear. A large trial of 646 children with rotavirus-driven diarrhea found no meaningful difference between probiotics and placebo. A smaller analysis did find probiotics shortened diarrhea by about two days. If you want to try them, look for products containing Saccharomyces boulardii or Lactobacillus rhamnosus GG, the two strains with the most research behind them. They’re unlikely to cause harm, but don’t expect a dramatic fix for every type of diarrhea.
How Long It Should Last
Acute diarrhea typically wraps up in less than a week without any specific treatment. If it stretches past two weeks, it’s considered persistent. Anything lasting four weeks or longer is classified as chronic and points to an underlying condition that needs investigation, such as irritable bowel syndrome, inflammatory bowel disease, food intolerances, or medication side effects.
One thing worth knowing: even after the infection clears, your digestive system may not feel completely normal for a while. Roughly 1 in 5 people who go through a significant bout of bacterial gastroenteritis develop ongoing gut symptoms that meet the criteria for irritable bowel syndrome. This doesn’t mean you’re stuck with it permanently, but if you notice lingering bloating, cramping, or irregular stools weeks after the diarrhea itself has stopped, that pattern is common and has a name.
Warning Signs That Need Attention
Most diarrhea is an inconvenience, not an emergency. But certain symptoms change the equation:
- Black, tarry stools or visible blood or pus in the stool
- High fever alongside the diarrhea
- Six or more loose stools per day
- Severe abdominal or rectal pain
- Signs of dehydration that aren’t improving with fluids, such as dizziness, confusion, or very dark urine
- Frequent vomiting that prevents you from keeping fluids down
- Duration beyond two days in adults without improvement
For children, the timeline is shorter. A child with diarrhea lasting more than one day, any fever in infants, or refusal to eat or drink for more than a few hours warrants prompt medical attention. Babies under 12 months, premature infants, and children with other medical conditions need even quicker evaluation.