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Information from Your Family Doctor

Gastroenteritis in Children: Treating Dehydration


Am Fam Physician. 2012 Jun 1;85(11):online.

  See related article on gastroenteritis in children.

What is gastroenteritis?

Gastroenteritis (GASS-tro-EN-ter-EYE-tiss), or the stomach flu, is diarrhea (three or more watery, loose stools in one day) that is caused by germs, food poisoning, or unclean water. Your child may also have an upset stomach, vomiting, or fever.

Is it serious?

Fluid and body chemicals called electrolytes are lost through diarrhea and vomiting. If your child loses too much fluid and electrolytes, he or she can get dehydrated. Dehydration can be serious if it is not treated.

How do I know if my child is getting dehydrated?

If your child is dehydrated, he or she may not urinate as often and the urine will be darker than usual. Your child may also be tired and not as active.

How is dehydration treated?

You should give your child an oral rehydration solution, or ORS, to replace the lost fluids and electrolytes. Don't give your child clear liquids, like sodas, chicken broth, or juice, instead of an ORS. You can buy an ORS (one brand: Pedialyte) at the drugstore or supermarket and keep it at home in case your child becomes sick.

Your child should breastfeed, bottle-feed, or eat normal foods after taking an ORS. Don't limit your child's foods to only the BRAT diet (bananas, rice, applesauce, and toast), and don't mix extra water into formula.

How much ORS should be given?

Using a syringe or spoon, you can give your child a small amount of the ORS every five minutes for three to four hours. Your doctor can help you decide the exact amount to give based on your child's weight. If your child continues to have diarrhea or vomiting, you may need to give him or her the ORS after each episode. When your child is no longer dehydrated, you can start a regular diet. If your child becomes dehydrated again, start the ORS treatment for another three to four hours.

When should I call the doctor?

You should contact the doctor if your child is not better within 24 hours of starting ORS, or if you are having problems with the ORS (for example, it doesn't work, it is hard to give it to your child, or your child can't keep it down).

Also contact your doctor if your child:

  • Has sunken eyes, less tears or saliva than usual, increased sleepiness, or irritability

  • Has a fever (100.4°F or more in children three months or younger, 101°F or more in older children)

  • Has other medical problems or was born early

  • Is younger than six months or weighs less than 18 pounds

  • Has diarrhea with blood in it

Can I prevent gastroenteritis?

If it is caused by germs, it can be spread from one child to another. Clean surfaces that have been touched by a child who has been sick, and make sure your child washes his or her hands often. Your child should be vaccinated against certain viruses that can cause gastroenteritis, such as rotavirus.

This handout is provided to you by your family doctor and the American Academy of Family Physicians. Other health-related information is available from the AAFP online at

This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.


Copyright © 2012 by the American Academy of Family Physicians.
This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact for copyright questions and/or permission requests.

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