Almost everyone has had stomach flu at one time in his life. This highly contagious illness has nothing to with the stomach or the influenza virus, despite the name most people use to describe it. Doctors call this malady viral gastroenteritis. It is the second most common illness in the United States, according to the National Digestive Disease Information Clearinghouse.
Diarrhea and Vomiting
Viral gastroenteritis causes vomiting, diarrhea and nausea. The viruses responsible for stomach flu damage the cells in the lining of the small intestine. These cells weep fluids, adding excess fluid to intestinal contents, resulting in watery stools and diarrhea. Persistent diarrhea and vomiting may result in dehydration. Symptoms usually appear within 4 to 48 hours after exposure and typically last for 1 to 2 days. People with severe cases of viral gastroenteritis may experience symptoms for up to 10 days. Call a doctor if you are not able to keep anything down for more than 24 hours, or if you have bloody vomit or blood in your stool.
Fever
Fever is often associated with inflammation and can cause headache and chills. A person with a fever may lose more fluids due to sweating as his temperature rises and falls. Call your doctor if you have a fever higher than 104 degrees F, according to MayoClinic.com. Talk to your pediatrician if your child has a fever over 102 degrees F, is lethargic, seems to be in pain or is suffering dehydration.
Dehydration
A person with severe stomach flu may experience dehydration associated with excessive vomiting and diarrhea. Dark urine or low urine output is a sign of dehydration. Prevent dehydration at home with increase fluid intake. Parents can give children electrolyte replacement drinks and adults can consume sports drinks. Call the doctor if your baby has not had a wet diaper in six hours, has a dry mouth or eyes, a sunken in forehead or is drowsy or lethargic. Adults suffering dehydration may experience excessive thirst, lightheadedness or dizziness. Severe dehydration can lead to an electrolyte imbalance and cardiac problems.
Weakness
You may feel weak while suffering from viral gastroenteritis. Fever, dehydration and nutrient loss due to excessive vomiting and diarrhea may cause weakness. Treat this weakness with plenty of liquids as tolerated, rest and slowly introducing soft and bland food into the diet. Avoid spicy, fatty foods. People who are lactose intolerant should not consume dairy products to avoid causing the return of signs and symptoms of stomach flu.
