Most stomach bugs resolve on their own within one to three days, and the single most important thing you can do is stay hydrated. A stomach bug, usually caused by norovirus or rotavirus, doesn’t respond to antibiotics. Treatment is about managing symptoms, replacing lost fluids, and eating again as soon as you’re able.
Fluids Are the Priority
Vomiting and diarrhea drain your body of water and electrolytes fast. Oral rehydration is the cornerstone of treatment for mild and moderate cases. This means more than just drinking water. You need to replace sodium, potassium, and sugar along with it. Oral rehydration solutions (like Pedialyte or store-brand equivalents) are specifically designed for this. Sports drinks are a second choice since they contain more sugar and less sodium than ideal, but they’re far better than nothing.
If you’re vomiting frequently, take small sips rather than gulping a full glass. A few tablespoons every five to ten minutes is a good starting pace. Your stomach is more likely to keep that down. Once you’ve gone 30 to 60 minutes without vomiting, gradually increase the amount. If vomiting is so severe and persistent that you can’t keep any fluid down, or if diarrhea is outpacing what you’re drinking, you may need intravenous fluids at an urgent care or emergency room.
Signs of Dehydration to Watch For
Mild dehydration causes thirst, dark urine, and a dry mouth. These are normal during a stomach bug and improve with steady fluid intake. More concerning signs include no tears when crying (especially in children), sunken eyes, dizziness when standing, and producing very little urine over several hours. In children specifically, a combination of dry mouth, no tears, a slow return of color when you press on the skin, and a generally ill appearance suggests at least a 5 percent fluid loss, which typically warrants medical attention.
Confusion or extreme drowsiness signals severe dehydration and requires emergency care.
What to Eat (and When)
You’ve probably heard of the BRAT diet: bananas, rice, applesauce, and toast. It’s a familiar recommendation, but the CDC considers it unnecessarily restrictive. It doesn’t provide enough nutrition to support recovery, and prolonged gut rest actually slows healing. The current guidance is to return to a normal, age-appropriate diet as soon as you can tolerate food. Withholding food for more than 24 hours is not recommended.
That said, “normal diet” doesn’t mean jumping straight to spicy or greasy meals. Start with bland, easy-to-digest foods: plain crackers, chicken broth, boiled potatoes, plain pasta, cooked vegetables. If it stays down, eat more. Your gut recovers faster when it has nutrients to work with. Avoid dairy for the first day or two if it seems to worsen diarrhea, since the infection can temporarily reduce your ability to digest lactose.
Over-the-Counter Medications
Anti-diarrheal medication containing loperamide (the active ingredient in Imodium) can reduce the frequency of watery diarrhea in adults. It’s generally not needed for a short-lived stomach bug, but it’s useful if you have to function at work or travel. Follow the package directions, and stop taking it once stools firm up. Loperamide should not be given to children under 2, and older adults should use it cautiously because of a small risk of heart rhythm issues at high doses.
Bismuth subsalicylate (the active ingredient in Pepto-Bismol) can help with nausea and diarrhea. It’s generally safe for adults but should be avoided in children and teenagers recovering from flu-like illness due to the risk of Reye’s syndrome.
Anti-nausea medications are typically reserved for severe, persistent vomiting that prevents you from keeping down any fluids. If you’re in that situation, a doctor can prescribe something. For most people, the vomiting phase of a stomach bug is the shortest part, often lasting less than 24 hours. Antibiotics are not appropriate and can actually cause harm since they don’t work against viruses and can disrupt your gut further.
Do Probiotics Help?
There’s some evidence that specific probiotic strains can shorten the duration of viral diarrhea. In one clinical trial, hospitalized children with viral gastroenteritis who received probiotics had diarrhea for about 60 hours compared to 86 hours in the placebo group. That’s roughly a full day less. Notably, the benefit appeared only for viral infections, not bacterial ones.
The catch is that “probiotics” is a broad category, and not every product on the shelf contains strains tested for gastroenteritis. If you want to try them, look for products that specify their strains and colony counts. They’re unlikely to cause harm, but they’re also not a substitute for rehydration.
How Long a Stomach Bug Lasts
Rotavirus symptoms typically start about two days after exposure, with vomiting and watery diarrhea lasting three to eight days. Norovirus tends to move faster, with symptoms appearing 12 to 48 hours after exposure and usually resolving within one to three days. In both cases, the vomiting often peaks in the first 24 hours, while diarrhea lingers longer.
Even after the worst symptoms pass, you may feel wiped out for several more days. Your gut lining needs time to repair, so mild bloating, low appetite, or loose stools for up to a week afterward is common and not a sign of a new problem. You also remain contagious for at least two days after symptoms stop, and sometimes longer, so hand hygiene matters even when you feel better.
Keeping It From Spreading
Norovirus is extraordinarily contagious. A tiny amount of viral particles can cause infection, and the virus survives on surfaces for days. Standard cleaning won’t cut it. You need a bleach solution: 5 to 25 tablespoons of regular household bleach (5% to 8% concentration) per gallon of water. Alternatively, use a disinfectant specifically registered as effective against norovirus. Wipe down bathroom surfaces, doorknobs, faucet handles, and light switches.
Wash your hands thoroughly with soap and water, not just hand sanitizer. Alcohol-based sanitizers are less effective against norovirus. Wash contaminated clothing and bedding on the hottest setting and dry on high heat. If someone in your household is sick, ideally they should use a separate bathroom. If that’s not possible, disinfect shared surfaces after every use until at least 48 hours after the sick person’s symptoms resolve.
Caring for a Sick Child
Children, especially those under 5, dehydrate faster than adults because of their smaller fluid reserves. Oral rehydration solution is the best option. Offer small amounts frequently rather than large volumes at once. For breastfed infants, continue breastfeeding, as breast milk provides both fluids and nutrients that support recovery. For formula-fed babies, continue with regular formula.
Don’t wait for signs of dehydration to start pushing fluids. If your child is vomiting, try a teaspoon or tablespoon every few minutes. Once they’ve kept fluids down for a couple of hours, offer food. As with adults, returning to a normal diet promptly is better than restricting them to bland foods for days. If your child can’t keep any fluids down for several hours, shows no tears, has a dry mouth, or seems unusually sleepy or floppy, they need medical evaluation.