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Gastroenteritis in Children


The Manual's Editorial Staff

Last full review/revision Dec 2019| Content last modified Dec 2019
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What is gastroenteritis?

Gastroenteritis is an infection of the digestive (also called the gastrointestinal, or GI) tract that causes throwing up, diarrhea, or both. The stomach and intestines are the main organs of the digestive tract. People sometimes make the mistake of calling gastroenteritis "stomach flu." But it isn't a "flu" and has nothing to do with influenza (flu).

  • Gastroenteritis is the most common GI problem in children

  • Children with gastroenteritis throw up and have diarrhea, belly cramps, and fever

  • Throwing up and having diarrhea can lead to dehydration (not having enough water or other fluids in the body), which can cause serious problems

  • You can help prevent gastroenteritis by keeping up with your child's vaccines and by having children wash their hands often

  • Gastroenteritis is treated by replacing water and electrolytes, usually by drinking a special liquid made for children with gastroenteritis

  • Children who can't keep down fluids should see a doctor—they may need an IV

What causes gastroenteritis?

Gastroenteritis is most often caused by a virus (such as rotavirus). It can also be caused by bacteria or parasites.

Children can get gastroenteritis by:

  • Touching infected children or their toys, and then putting their fingers in their mouth

  • Being near a sick child who is sneezing or spitting

  • Eating food or drinking liquid that has bacteria in it (this is called food poisoning)

  • Drinking unpasteurized milk or juice (unpasteurized means it wasn't heated to kill germs)

  • Touching reptiles, birds, frogs, or salamanders that carry bacteria

  • Eating certain plants or medicines

  • Swallowing infected water from swimming pools, water parks, or streams

What are the symptoms of gastroenteritis?

Symptoms include:

  • Throwing up

  • Diarrhea

  • Belly cramps

  • Not feeling hungry

Sometimes, certain types of gastroenteritis cause bloody diarrhea. This is more serious, and you should take your child to the doctor right away.

What are the complications of gastroenteritis?

The main complication is:

  • Dehydration

Dehydration is too little water or other fluid in the body. This can be dangerous. Babies are more likely to get dehydrated because they're smaller.

Your baby is dehydrated and needs to see a doctor right away if your baby:

  • Has a sunken soft spot on the top of the head (all babies have a soft spot, but it shouldn't be sunken)

  • Has sunken eyes

  • Has a dry mouth

  • Has no tears when crying

  • Isn't peeing much

  • Is less alert and has less energy

Your child is dehydrated and needs to see a doctor right away if your child:

  • Isn't peeing much and hasn't peed for 6 hours or more

  • Is cranky and sluggish

  • Has a dry mouth

How can doctors tell if my child has gastroenteritis?

Your child's symptoms and a physical exam help doctors tell if your child has gastroenteritis. Usually no blood tests or stool tests are needed. Sometimes your doctor needs to know what kind of infection caused the gastroenteritis and will take a cotton swab of the diarrhea for testing.

How do doctors treat gastroenteritis?

For babies, doctors treat gastroenteritis by having them:

  • Continue to breastfeed or drink formula

  • Drink a special rehydration solution (oral electrolyte solution—powders or liquids are sold in pharmacies and grocery stores)

For older children, doctors' advice is:

  • Have your child drink fluids, such as an oral electrolyte solution on the first day of sickness—teens may drink a sports drink instead of soda or juice

  • If your child is throwing up, give small sips of fluid every 10 or 15 minutes—if your child doesn't throw up, gradually give a little more fluid

  • In a 24-hour period, your child should drink at least 1½ ounces of fluid for every pound of body weight

  • If your child has diarrhea, give more fluid than usual

  • Have your child eat a normal diet if able—special foods aren't necessary

  • If your child has diarrhea, offer less dairy (such as milk or butter)

Your child’s doctor may give:

  • Fluids into the vein (IV) if your child is dehydrated

  • Medicines to prevent throwing up or to help slow down diarrhea

  • Antibiotics if the cause is certain kinds of bacteria

  • Antiparasitic drugs if the cause is a parasite

How can I prevent gastroenteritis?

To help prevent gastroenteritis:

  • Make sure your child gets the rotavirus vaccine, which is one of the standard vaccines

  • Have children regularly wash their hands

  • Store foods properly (keep cold foods cold and hot foods hot), and don't let your child eat food that has been sitting out longer than an hour

  • Keep diaper changing areas clean (and regularly disinfect with a solution of ¼ cup bleach in 1 gallon of water)

  • Breastfeed

  • Don’t let children or babies with weak immune systems touch reptiles, birds, or amphibians

  • Teach your child to avoid swallowing water when swimming

To help prevent the spread of gastroenteritis:

  • A child with loose stools (diarrhea) should stay home from school or daycare and shouldn't swim in public water

  • Check your child’s diaper often and change it away from the public water

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