Stomach flu, sometimes called gastroenteritis, is inflammation of the stomach and intestines. It can be caused by a viral, bacterial, or a parasitic infection, but it is not caused by the influenza virus.
The symptoms of gastroenteritis include nausea, vomiting, abdominal (belly) cramps, diarrhea, fever, and weight loss.
Stomach flu usually goes away without medical treatment in 1 to 2 days. Home treatment can relieve the symptoms of stomach flu and prevent problems, such as dehydration.