Most stomach bugs last 1 to 3 days in otherwise healthy adults. The specific timeline depends on which pathogen caused the infection, your age, and how well your immune system is functioning. Some people bounce back in 24 hours, while others deal with symptoms for up to two weeks.
Timelines by Type of Infection
The term “stomach bug” covers several different infections, and each one runs on its own clock.
Norovirus is the most common culprit in adults. Symptoms hit fast, typically 12 to 48 hours after exposure, and last 1 to 3 days. It tends to come on suddenly with intense vomiting and diarrhea, then clears almost as quickly as it arrived.
Rotavirus is more common in young children and tends to drag on longer. Vomiting and watery diarrhea from rotavirus typically last 3 to 8 days. Adults can catch it too, though symptoms are usually milder.
Bacterial infections from contaminated food (think Salmonella or Campylobacter) can overlap with viral symptoms but often last longer, sometimes a full week or more. Bloody diarrhea or a high fever that persists beyond a couple of days can signal a bacterial cause rather than a viral one.
What the First Few Days Look Like
The pattern is fairly predictable. After the incubation period (12 to 48 hours for norovirus), symptoms usually peak within the first 24 hours. Vomiting often stops first, sometimes within a day. Diarrhea tends to hang around a bit longer, tapering off over the next one to three days. Fatigue and a lack of appetite commonly linger even after the worst is over.
Most people feel noticeably better by day two or three. If you’re still dealing with frequent vomiting or diarrhea past that point, your body may be fighting a different type of infection, or dehydration may be slowing your recovery.
Why It Lasts Longer in Children and Older Adults
Healthy adults typically recover without complications, but the timeline stretches for people at either end of the age spectrum. Infants and young children have immune systems that are still maturing, making them more vulnerable to prolonged illness. Rotavirus infections hit this group especially hard.
Older adults face a similar challenge. Immune function naturally becomes less efficient with age, and people in nursing homes or assisted living are particularly susceptible to longer, more severe bouts. Anyone with a weakened immune system, regardless of age, can experience symptoms lasting up to 14 days.
The biggest risk for all these groups is dehydration. Young children and older adults lose fluids faster than they can replace them. Warning signs include noticeably decreased urination, unusual drowsiness or irritability, and a dry mouth. In infants, watch for fewer wet diapers and no tears when crying.
How Long You Stay Contagious
Here’s the part most people don’t realize: you’re still contagious after you feel better. With norovirus, you can spread the virus for days after your symptoms resolve. Current CDC guidelines recommend that healthcare workers and food handlers stay away from work for at least 48 hours after their last symptom. That 48-hour rule is a good benchmark for everyone, not just people in those jobs.
Thorough handwashing matters more than hand sanitizer here. Norovirus is notoriously resistant to alcohol-based sanitizers, so soap and water is the more effective option, especially before preparing food or touching shared surfaces.
Eating and Drinking During Recovery
Staying hydrated is the single most important thing you can do while a stomach bug runs its course. Small, frequent sips of water, diluted juice, or an oral rehydration solution work better than trying to drink large amounts at once, which can trigger more vomiting.
You don’t need to wait until symptoms fully stop before eating again. Once you can keep fluids down, start with small amounts of bland, easily digestible food. Plain rice, toast, bananas, and broth are common choices. Avoid dairy, fatty foods, and anything heavily seasoned until your gut settles. For children who are breastfeeding, increasing the frequency and duration of feeds during and after illness helps with both hydration and recovery. After the diarrhea stops, offering an extra meal each day for about a week can help children regain any weight lost during the illness.
When Gut Symptoms Stick Around for Weeks
For most people, a stomach bug is a miserable few days and nothing more. But roughly 1 in 10 people who get a gut infection develop a condition called post-infectious IBS, where bloating, cramping, or irregular bowel habits persist long after the original bug is gone. This isn’t a sign that you’re still infected. It’s your digestive system recalibrating after the disruption.
Post-infectious IBS can last months or, in some cases, years. About half of cases resolve on their own within six to eight years. If you’re still experiencing digestive issues weeks after a stomach bug, that lingering sensitivity is worth discussing with a doctor, especially if it’s affecting what you can eat or how you go about your day.