How long does a stomach virus last?

According to WebMD, stomach flu viruses can last up to 10 days. Symptoms, such as vomiting and diarrhea, are typically the most severe during the first two days of infection. In most cases, stomach viruses resolve on their own without medication.

Mayo Clinic explains that symptoms of the stomach flu typically develop within one to three days following initial infection. Adults with stomach viruses should consult with a physician immediately if they experience symptoms of dehydration, vomit blood or notice blood in their stools. Parents should seek urgent medical attention if their children have excessive diarrhea, appear lethargic or experience severe pain.