You can’t kill a stomach virus with medication the way you’d treat a bacterial infection with antibiotics. The virus has to run its course, and most people recover within one to three days. What you can control is how miserable those days are and how quickly your body bounces back. The real work is managing dehydration, eating strategically, and avoiding mistakes that drag out your symptoms.
Why You Can’t “Cure” It, Only Manage It
Viral gastroenteritis, the medical term for a stomach virus, is most commonly caused by norovirus in adults and rotavirus in young children. These viruses inflame the lining of your stomach and intestines, triggering vomiting, diarrhea, cramps, and sometimes fever. No antiviral medication exists for either one. Your immune system clears the infection on its own, typically within one to three days for norovirus. For some people, especially older adults and very young children, symptoms can linger a bit longer.
Everything below is about shortening your recovery, preventing complications, and keeping the virus from spreading to everyone else in your household.
Hydration Is the Single Most Important Thing
Dehydration is the main danger of a stomach virus, not the virus itself. Every episode of vomiting or diarrhea pulls water, sodium, and potassium out of your body. Replacing plain water alone isn’t enough because your intestines absorb fluid most efficiently when sodium and glucose are present together. That’s the principle behind oral rehydration solutions: they contain a precise blend of salt, sugar, and electrolytes designed to maximize water absorption through your gut wall.
Premixed rehydration solutions are available at most pharmacies and grocery stores. They have higher sodium and potassium levels than sports drinks, with less sugar. Sports drinks like Gatorade were formulated for athletes losing sweat, not for people with severe diarrhea. The sugar content in sports drinks is substantially higher, which can actually pull more water into the intestines and worsen diarrhea in some cases. If a rehydration solution is all you have access to, use it. If you only have sports drinks, diluting them with water is a reasonable backup.
Sip small amounts frequently rather than gulping a full glass. If you’re vomiting, try a few tablespoons every 10 to 15 minutes. Ice chips work well when even small sips won’t stay down. As vomiting slows, gradually increase the volume. Signs you’re staying hydrated include urinating at a normal frequency and having light-colored urine.
What to Eat (and When)
The old advice was to follow the BRAT diet: bananas, rice, applesauce, and toast. This is outdated. The CDC’s own clinical guidance calls the BRAT diet “unnecessarily restrictive,” noting it provides suboptimal nutrition for a recovering gut. The current recommendation is to return to a normal, age-appropriate diet as soon as you can tolerate food. Gut rest is not indicated.
In practical terms, that means once your vomiting has stopped or significantly slowed, start eating whatever sounds tolerable. Bland foods like crackers, plain pasta, boiled potatoes, and broth are fine starting points, not because they’re medically special, but because they’re easy on a sensitive stomach. If you feel ready for chicken, eggs, or cooked vegetables, go for it. Your intestines need calories and protein to repair themselves. Avoid greasy, very spicy, or heavily sweetened foods for the first day or two simply because they’re more likely to trigger nausea.
Dairy is worth a brief mention. Some people develop temporary lactose intolerance after a stomach virus because the infection damages the cells that produce the enzyme needed to digest milk sugar. If dairy seems to worsen your symptoms, skip it for a few days and reintroduce it gradually.
Over-the-Counter Medications
Anti-diarrheal medications containing loperamide (the active ingredient in Imodium) can reduce the frequency of diarrhea. They work by slowing the movement of your intestines. However, they should not be used if you have a fever or notice blood in your stool, as these could signal a more serious infection where slowing the gut down would be harmful.
Bismuth subsalicylate (the active ingredient in Pepto-Bismol) can help with nausea and diarrhea, but it carries important restrictions. It should not be given to children under 12 and is not recommended for children 18 or younger who have a viral infection due to the risk of Reye’s syndrome. Pregnant women, people with kidney problems, and anyone on blood thinners should also avoid it. If you’re already taking aspirin or any salicylate-containing medication, adding bismuth subsalicylate raises the risk of toxicity.
For fever and body aches, acetaminophen is generally the gentlest option on an already irritated stomach.
Do Probiotics Help?
There’s reasonable evidence that certain probiotics can modestly shorten the duration of acute infectious diarrhea when taken alongside rehydration. A European pediatric gastroenterology group recommends specific strains for children with acute diarrhea, and the general findings apply to adults as well. Interestingly, research suggests it doesn’t matter much which strain you pick, whether you use a single strain or a blend, or whether the dose is high or low. The effects are relatively consistent across products.
If you want to try probiotics, start them as soon as symptoms begin and continue for five to ten days. They won’t dramatically change the course of your illness, but shaving even half a day off diarrhea symptoms is worth it for most people. Look for products containing well-studied strains, which are commonly available at drugstores.
How Long You’re Contagious
This is where stomach viruses get tricky. You’re most contagious while you have symptoms, especially during active vomiting. But the virus doesn’t leave your body when you start feeling better. You remain contagious for the first few days after symptoms resolve, and studies have shown that norovirus can still be shed for two weeks or more after recovery.
This means you should stay home from work or school for at least 48 hours after your last episode of vomiting or diarrhea. If you prepare food for others, that window matters even more, since norovirus spreads easily through contaminated food. During those two weeks of potential shedding, thorough handwashing after using the bathroom is essential.
Cleaning and Prevention
Alcohol-based hand sanitizers are not reliable against norovirus. The virus lacks the outer fatty envelope that alcohol dissolves on most other pathogens, making it particularly resistant to standard sanitizers. Some ethanol-based formulations can reduce viral levels when applied thoroughly for 30 seconds, but they’re significantly less effective than soap and water. Wash your hands with soap and water for at least 20 seconds, especially after using the bathroom and before eating.
For surfaces, norovirus can survive on countertops, doorknobs, and light switches for days. Clean contaminated surfaces with a bleach-based solution. If someone in your house vomits, the spray of tiny droplets can land several feet away, so clean a wider area than you think is necessary. Wash contaminated clothing and linens on the hottest setting available and dry them completely.
Signs of Dehydration That Need Attention
Most stomach viruses resolve without medical care, but dehydration can escalate quickly, particularly in young children and older adults. In adults, warning signs include extreme thirst, dark urine, dizziness, confusion, and skin that stays tented when you pinch it rather than flattening back immediately.
In infants and young children, watch for no wet diapers for three hours or more, no tears when crying, a dry mouth, sunken eyes, rapid heartbeat, or unusual crankiness and lethargy. Skin that doesn’t bounce back after a gentle pinch is another red flag at any age.
Other reasons to seek medical care: diarrhea lasting more than 24 hours, inability to keep any fluids down, bloody or black stool, or a fever at or above 102°F.