Diarrhea from a stomach bug typically lasts 1-3 days, but it can persist for up to 10 days in severe cases. The duration depends on the cause, your hydration status, and health.
A stomach bug, or acute gastroenteritis, inflames the stomach and intestines. Viruses like norovirus or rotavirus often trigger rapid, watery diarrhea within 12-48 hours of infection. Bacteria such as E. coli or Salmonella may cause more severe diarrhea starting 1-3 days later.
| Cause | Typical Onset | Duration |
|---|---|---|
| Norovirus | 12-48 hours | 1-3 days |
| Rotavirus | 1-3 days | 3-7 days |
| Salmonella | 6-72 hours | 4-7 days |
| E. coli | 3-8 days | 5-10 days |
Diarrhea lasting more than 3 days could indicate a bacterial infection or parasite. Persistent symptoms beyond 10 days may signal post-infectious irritable bowel syndrome (IBS), requiring medical evaluation. Dehydration worsens recovery times, so drink small sips of water, clear broths, or oral rehydration solutions frequently.
Most stomach bugs resolve without treatment. Antidiarrheal medications like loperamide can reduce frequency but may prolong infection by trapping bacteria. Consult a doctor if diarrhea contains blood, persists beyond 10 days, or causes severe dehydration (dark urine, dizziness, or infrequent urination).
I once had a norovirus infection that caused 24 hours of intense diarrhea despite minimal other symptoms. Staying hydrated with electrolyte drinks helped me recover within 36 hours-a shorter duration than expected.
Wash hands frequently with soap and water, especially after using the restroom or before eating. Avoid undercooked foods and unpasteurized dairy. If traveling, drink bottled water and avoid ice in drinks. The CDC recommends getting vaccinated against rotavirus for infants and norovirus for high-risk groups.
Contact a healthcare provider if diarrhea lasts longer than 3 days in adults or 24 hours in children. Seek immediate care for signs of severe dehydration, bloody stools, or a temperature above 101.5°F (38.6°C). Persistent symptoms may require stool tests to identify bacterial or parasitic causes.
Most stomach bugs clear up within a week. Understanding typical durations helps distinguish normal recovery from complications needing medical attention.