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Symptoms and Signs of Gastroenteritis (Stomach Flu) In Children and Adults

Doctor's Notes on Gastroenteritis (Stomach Flu) In Children and Adults

Gastroenteritis is inflammation of the lining of the stomach and small intestine. It causes symptoms that are commonly referred to as the “stomach flu”, but the condition is not related to influenza. Viral infections are the most common cause of gastroenteritis, but certain bacteria can also cause the condition. Rotavirus and norovirus are the two main causes of viral gastroenteritis. Parasitic infections, toxins, and drugs are other possible causes of gastroenteritis.

Signs and symptoms of gastroenteritis include loss of appetite, nausea, vomiting, diarrhea, and abdominal pain. The diarrhea of viral gastroenteritis typically does not contain blood and may be watery. Some types of bacterial gastroenteritis can cause bloody diarrhea. Other associated signs and symptoms can include fever, chills, headache, muscle aches, and fatigue.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.