Most stomach viruses last one to two days, though some cases stretch to three days before symptoms fully clear. The worst of it, especially the vomiting, often passes within the first 24 hours, while diarrhea can linger a bit longer. How quickly you recover depends on which virus you caught, your age, and your overall health.
What the Timeline Looks Like
Stomach viruses don’t hit immediately after exposure. There’s a gap between picking up the virus and feeling sick. For norovirus, the most common culprit in adults, that incubation period is 12 to 48 hours. Other viruses that cause gastroenteritis can take one to three days to produce symptoms.
Once symptoms start, they tend to follow a predictable pattern. Nausea and vomiting usually come first and are most intense in the first 12 to 24 hours. Watery diarrhea, stomach cramps, and sometimes a low fever overlap with or follow the vomiting. Headaches and muscle aches are common too, and they can make you feel like you have the flu even though stomach viruses are unrelated to influenza.
For most adults, the active illness wraps up within one to two days. Children and older adults may take closer to three days, and their risk of dehydration is higher because they lose fluids faster and replace them more slowly.
You’re Still Contagious After You Feel Better
One of the most important things to know is that your symptoms ending doesn’t mean you’ve stopped spreading the virus. According to the CDC, people with norovirus can continue shedding the virus in their stool for two weeks or more after they feel completely normal. The most contagious window runs from the start of symptoms through 48 hours after they stop.
Because of that timeline, the standard recommendation is to stay home from work or school until at least 48 hours after your last episode of vomiting or diarrhea. This isn’t just a courtesy. Norovirus is extremely easy to transmit, and returning too soon is one of the main ways outbreaks spread through offices, schools, and daycare centers.
Dehydration Is the Real Danger
The virus itself isn’t what sends people to the emergency room. Dehydration is. When you’re vomiting and having diarrhea simultaneously, you can lose fluids faster than you can replace them, especially if even small sips of water won’t stay down.
In adults, watch for these signs that dehydration is becoming serious:
- Dark-colored urine or urinating much less than normal
- Extreme thirst that doesn’t resolve with sipping fluids
- Dizziness, confusion, or unusual sleepiness
- Skin that stays pinched up instead of flattening back when you pinch and release it
In babies and young children, the warning signs look different. No wet diapers for three hours, no tears when crying, a dry mouth, sunken eyes, or unusual crankiness all signal that a child needs medical attention. A fever above 102°F, bloody stool, or an inability to keep any fluids down for 24 hours also warrants a call to your doctor, regardless of age.
Why Some People Feel Off for Weeks
Even after the vomiting and diarrhea are long gone, some people notice their digestion doesn’t feel right. Bloating, gas, cramping, or alternating bouts of loose stool and constipation can hang around for weeks. In most cases, this is just the gut lining recovering and rebalancing, and it resolves on its own.
For a smaller group, roughly 1 in 10 people who get a gut infection, these lingering symptoms become something called post-infectious IBS. It produces the same bloating, pain, and irregular bowel habits as other forms of irritable bowel syndrome, but it’s triggered directly by the infection. Post-infectious IBS can persist for years, though about half of cases resolve on their own within six to eight years. Cutting back on dairy, wheat, or gluten helps some people manage symptoms in the meantime. Temporary lactose intolerance is also common after a stomach virus because the infection can damage the cells in your intestinal lining that produce the enzyme needed to digest dairy. This usually clears up within a few weeks.
What Actually Helps You Recover
There’s no medication that kills a stomach virus. Your immune system handles that on its own. What you can control is how well you manage fluids and ease back into eating.
Small, frequent sips of water, broth, or an oral rehydration solution work better than gulping large amounts, which can trigger more vomiting. Once you can keep liquids down for a few hours, plain foods like toast, rice, bananas, and crackers are easy starting points. There’s no need to follow a rigid diet, though. Eat what sounds tolerable and avoid anything greasy, spicy, or heavy on dairy until your stomach feels more settled.
For preventing spread within your household, hand washing with soap and water is the single most effective step. Alcohol-based hand sanitizers do not work well against norovirus. You can use them as a supplement, but they’re not a substitute for soap and water. Clean contaminated surfaces with a bleach-based cleaner, and wash any soiled clothing or bedding on the hottest cycle the fabric allows.