The stomach flu (viral gastroenteritis) has no cure, but the right combination of fluids, rest, and food choices can significantly shorten your misery and prevent complications. Most cases resolve within 3 to 8 days, with vomiting typically tapering off before diarrhea does. The single most important thing you can do is stay hydrated, and everything else builds on that foundation.
Fluids Are the Top Priority
Vomiting and diarrhea drain your body of water and essential minerals like sodium and potassium far faster than you’d lose them on a normal day. Dehydration is the main reason people end up in the emergency room with stomach flu, and it’s largely preventable at home with the right approach.
Plain water alone isn’t ideal because it doesn’t replace the salts you’re losing. Oral rehydration solutions (sold as Pedialyte, DripDrop, or store-brand equivalents) are specifically designed for this. The WHO formula contains a precise balance of sodium and glucose that helps your intestines absorb fluid more efficiently. For adults, broth-based soups and diluted sports drinks can also work in a pinch, though they contain more sugar than optimal.
The trick when you’re actively vomiting is to start incredibly small. Take one teaspoon (about 5 mL) of fluid at a time, then wait a few minutes before the next sip. Gradually increase the amount as your stomach tolerates it. Gulping a full glass will often come right back up. For children, aim for 2 to 4 ounces of rehydration solution after each episode of vomiting or watery stool if they weigh under about 22 pounds, and 4 to 8 ounces if they weigh more. For moderate dehydration in children, the CDC recommends roughly 50 to 100 mL per kilogram of body weight over 2 to 4 hours to catch up on lost fluid.
Signs you’re getting dehydrated include dark yellow urine, dizziness when standing, dry mouth, and in children, fewer wet diapers or crying without tears. These are signals to push fluids harder or seek medical help.
What to Eat (and When)
You’ve probably heard of the BRAT diet: bananas, rice, applesauce, and toast. While those foods are gentle on the stomach, current guidelines actually recommend returning to a normal, age-appropriate diet as soon as you can tolerate it rather than restricting yourself to bland foods for days. Early refeeding helps your gut lining recover faster.
That said, there’s a practical middle ground. During the first 12 to 24 hours when nausea is at its worst, don’t force yourself to eat. Focus on fluids. Once you feel ready, start with small portions of simple foods: crackers, plain rice, bananas, boiled potatoes, or chicken broth. Avoid greasy, spicy, or high-sugar foods until your digestion feels more settled. Dairy can be harder to digest temporarily because the virus disrupts the enzyme that breaks down lactose, so you may want to ease back into milk and cheese over a few days.
Over-the-Counter Medications That Help
Anti-diarrheal medications containing loperamide (the active ingredient in Imodium) can reduce the frequency of bowel movements and are especially useful if you need to travel or get through a workday. However, you should avoid loperamide if you have a fever alongside bloody diarrhea, as those symptoms may indicate a bacterial infection where slowing your gut down could make things worse. Loperamide is generally not recommended for children under 6.
Bismuth subsalicylate (Pepto-Bismol) can help with nausea and diarrhea, but it comes with more restrictions than people realize. It contains a salicylate compound related to aspirin, so it’s off-limits if you have an aspirin allergy, kidney problems, or gout, or if you take blood thinners. It should not be given to children under 12, and many providers extend that caution to anyone 18 or younger during a viral infection because of the small risk of a serious condition called Reye’s syndrome.
Ginger for Nausea
Ginger is one of the better-studied natural remedies for nausea, and the evidence supports it. Clinical trials have used dosages ranging from 250 mg to 1 g taken three to four times daily, with no added benefit from going above 1 g per day. You can get this from ginger capsules, ginger chews, or strong ginger tea made from fresh root. About 10% of people in studies experienced mild heartburn from ginger, so if your stomach is already very irritated, start with a small amount. Flat ginger ale, despite its reputation, typically contains very little actual ginger and a lot of sugar, making it a poor choice.
Do Probiotics Help?
There’s reasonable evidence that certain probiotics can shorten the duration of diarrhea during gastroenteritis. A meta-analysis of 14 studies covering over 1,700 children found that probiotic supplementation reduced diarrhea duration by about 23 hours on average and shortened hospital stays by roughly 18 hours. The strains most commonly studied include species of Lactobacillus, Bifidobacterium, and a yeast called Saccharomyces boulardii.
Probiotics aren’t a dramatic fix, but shaving nearly a full day off your symptoms is meaningful when you’re miserable. They’re available over the counter in capsule, powder, or liquid form. If you’re going to try them, start as early in the illness as possible for the best effect.
Zinc for Children With Diarrhea
The WHO recommends zinc supplementation for children with acute diarrhea: 20 mg per day for 10 to 14 days, or 10 mg per day for infants under six months. Zinc helps the intestinal lining repair itself and can reduce the severity and duration of diarrheal episodes. This recommendation is particularly relevant in settings where zinc deficiency is common, but it’s a low-risk supplement worth discussing with your child’s pediatrician.
How Long the Stomach Flu Lasts
Symptoms typically begin about two days after exposure to the virus. Norovirus, the most common cause in adults, tends to peak within the first 1 to 3 days and resolves in 1 to 3 days for most people, though some feel wiped out for longer. Rotavirus, more common in young children, can cause vomiting and watery diarrhea lasting 3 to 8 days. The pattern usually follows a predictable arc: nausea and vomiting hit hardest in the first 24 to 48 hours, then diarrhea takes over and gradually tapers.
You may feel weak and have a reduced appetite for several days after the worst symptoms pass. This is normal. Your gut lining takes time to fully regenerate, so loose stools and mild cramping can linger for up to a week even after the virus itself has cleared.
Preventing Spread at Home
Norovirus is extraordinarily contagious. It takes fewer than 100 viral particles to infect someone, and a single episode of vomiting can release millions. If one person in your household is sick, aggressive cleaning is worth the effort.
Regular soap and most common household cleaners don’t reliably kill norovirus. The CDC recommends disinfecting contaminated surfaces with a bleach solution: 5 to 25 tablespoons of standard household bleach (5% to 8% concentration) per gallon of water. That’s a noticeably strong solution, so ventilate the area and wear gloves. Any EPA-registered disinfectant labeled as effective against norovirus also works. Focus on bathroom surfaces, doorknobs, light switches, and faucet handles.
Wash contaminated clothing and linens on the hottest water setting and dry on high heat. The sick person should avoid preparing food for others for at least two days after symptoms stop, as they can still shed the virus during that window. Frequent handwashing with soap and water (not just hand sanitizer, which is less effective against norovirus) is the single best way to break the chain of transmission.