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Gastroenteritis in Children


The Manual's Editorial Staff

Reviewed/Revised Oct 2023
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What is gastroenteritis?

Gastroenteritis is an infection of the digestive tract (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 Influenza (Flu) Influenza, often called the flu, is a viral infection that affects your lungs and airways. Flu symptoms are a little bit like the common cold but are much more severe. Influenza, often called... read more (flu).

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

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 should drink a sports drink instead of soda or juice, but an oral electrolyte solution is preferable.

  • 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:

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 pools or other public swimming areas

  • Check your child’s diaper often and change it away from the public pools and swimming areas

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