The most important thing to take for stomach flu is fluids. Viral gastroenteritis causes vomiting and diarrhea that drain your body of water and electrolytes fast, and replacing those losses matters far more than any medication. Beyond hydration, a few over-the-counter options can ease symptoms while you ride it out, which typically takes one to three days.
Fluids and Electrolytes Come First
Dehydration is the real danger with stomach flu, not the virus itself. Small, frequent sips work better than gulping a full glass, especially if you’re still vomiting. Water is fine for mild cases in adults, but drinks with electrolytes (sodium, potassium, and a small amount of sugar) help your body absorb fluid faster. Oral rehydration solutions like Pedialyte are the gold standard for children and also work well for adults. Sports drinks contain more sugar than ideal, but they’re better than nothing if that’s what you have on hand.
For babies and young children, watch diaper output closely. No wet diaper for three hours or more signals dehydration that needs medical attention. In adults, warning signs include not urinating at all, rapid heartbeat, confusion, or fainting.
Over-the-Counter Medications for Diarrhea
Adults can use loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol) to manage diarrhea from stomach flu. Loperamide slows gut movement, giving your intestines more time to absorb water. Bismuth subsalicylate coats the stomach lining and can also help with nausea.
There are important limits. Don’t use either medication if you have a fever or bloody diarrhea, because those symptoms suggest a bacterial or parasitic infection rather than a virus, and slowing your gut down in that situation can make things worse. Neither medication is considered safe for infants and children without a doctor’s guidance. Bismuth subsalicylate in particular carries a risk of Reye’s syndrome in kids, a rare but serious condition.
Managing Nausea and Vomiting
For most adults, nausea from stomach flu passes within 24 hours without medication. If vomiting is severe enough that you can’t keep any fluids down, a prescription anti-nausea medication like ondansetron (Zofran) can help. In clinical trials, a single oral dose reduced the need for IV fluids by more than 50% compared to placebo. Your doctor or an urgent care provider can call this in quickly. One trade-off to know: ondansetron can increase diarrhea, so it’s most useful when vomiting is your main problem rather than loose stools.
Ginger is a reasonable natural option for mild nausea. A small double-blind trial in children with acute gastroenteritis found that ginger (given as a 10 mg dose) helped reduce vomiting compared to placebo. Ginger tea, ginger chews, or flat ginger ale may take the edge off, though they won’t stop severe vomiting.
Pain and Fever Relief
Acetaminophen (Tylenol) is the safest choice for fever or body aches during stomach flu. Ibuprofen (Advil, Motrin) can irritate an already inflamed stomach lining and potentially worsen nausea, so it’s best avoided until your gut settles down. This applies to both adults and children.
Skip the Probiotics
Probiotics are widely marketed for gut health, but the evidence for stomach flu is surprisingly weak. A large study through the Pediatric Emergency Care Applied Research Network tested Lactobacillus rhamnosus GG, one of the most studied probiotic strains, in children with acute gastroenteritis. The result: no significant difference from placebo in symptom severity, duration of diarrhea, duration of vomiting, or household transmission. Taking a probiotic won’t hurt you, but don’t count on it to shorten your illness.
What to Eat (and When)
The old advice to stick to the BRAT diet (bananas, rice, applesauce, toast) has fallen out of favor. Current guidance from the NIDDK is straightforward: go back to your normal diet as soon as your appetite returns, even if you still have some diarrhea. Research shows that restricted diets don’t help treat viral gastroenteritis, and eating normally helps your gut lining recover faster.
That said, common sense still applies. Most people naturally gravitate toward bland, easy-to-digest foods when their stomach is unsettled. That’s fine. Just don’t force yourself to fast or limit your diet once you feel ready to eat. For children, give them whatever they normally eat as soon as they’re willing. Breast-fed infants should continue nursing throughout the illness.
Signs You Need More Than Home Treatment
Most stomach flu resolves on its own, but dehydration can escalate quickly in young children, older adults, and people with chronic health conditions. Seek medical care if you notice:
- No urination for six or more hours in adults, or no wet diaper for three hours in infants
- Bloody diarrhea or vomit
- Fever above 104°F (40°C)
- Confusion, rapid heartbeat, or rapid breathing
- Inability to keep any fluids down for more than 12 to 24 hours
These signs point to dehydration severe enough to need IV fluids, or to an infection that isn’t viral and requires different treatment.