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Diarrhea is the frequent passage of unformed bowel movements. Its important to know what your childs stools usually look like. If the stools increase in number or become runnier than usual, this is considered an important change. Newborns often stool 8 – 10 times a day, sometimes passing small, watery stools mixed with yellow, seedy pieces. This is normal and is not a cause for concern.

What are the causes of diarrhea in children?

1.The most common cause of diarrhea is a viral infection of the intestines (“stomach bug” or gastroenteritis).

  • Rotavirus – one of the most common causes of diarrhea

* Rotavirus infects nearly all children by age 4

* It causes over 3 million cases of illness in the United States
each year

* It occurs in late fall to early spring but this will vary by region
(e.g., the peak season in the Southwest is November -
December; Southeast is March-April)

* Most children are infected more than once with the repeat
infections usually being milder

2.  Bacteria (e.g., Salmonella) or parasites can cause diarrhea but much less commonly.

  • Bacterial infections can cause bloody stools
  • Parasites generally cause very watery diarrhea

Some other causes include:

  • Food allergy (e.g., milk protein allergy)- Due to an allergy to the protein in dairy products- Your child may start to develop diarrhea (which may
    be bloody), rash on the face, body, and diaper area,
    runny nose, cough, or wheezing.
  • Lactose intolerance- Due to trouble digesting the sugar, lactose found in dairy
    products- Symptoms include gassy pain, stomach cramps, nausea,
    and diarrhea
  • Antibiotic use
  • Inflammatory bowel disease
  • Hirschsprung’s disease
  • Poor absorption as seen with cystic fibrosis, celiac disease

How does a child get gastroenteritis?

  • As with many intestinal infections, a child may become ill after touching stool from an infected person or a surface that has been contaminated with the stool and then placing their hands in their mouths.

How long will it take my child to become ill after being exposed to someone else with gastroenteritis?

  • Remember, just because your child is exposed to an ill person does not necessarily mean they, too, will become ill.
  • But if your child is to become ill, it usually takes 2 to 4 days to become ill after being exposed to most viruses.

What are the signs and symptoms of gastroenteritis?

  • Diarrhea
  • Vomiting
  • Fever
  • Abdominal pain
  • Loss of appetite
  • For rotavirus, children usually first have fever and vomiting then develop watery diarrhea 1 – 2 days later.· The child may have 10 – 20 bowel movements per day· The bowel movements are typically foul smelling, watery,
    green or brown· Dehydration may result from a rotavirus infection· The vomiting usually only lasts for a day

What signs and symptoms may suggest a serious cause for the diarrhea and require immediate medical treatment?

  • Blood in the stool
  • Frequent vomiting
  • Persistent or increasing abdominal pain
  • High fever
  • Weight loss

How can gastroenteritis be diagnosed?

  • For the most part, gastroenteritis is a clinical diagnosis meaning that the diagnosis is based on the child’s symptoms and physical examination.
  • However, stool studies can be done in some situations to detect whether a virus or bacteria is the cause of the illness.

How long will my child be sick with gastroenteritis?

  • The length of a diarrhea illness can vary from a couple of days to a couple of weeks. Symptoms from the common viral infection Rotavirus usually lasts 3 – 8 days.
  • On average, children still have Rotavirus in their stool for 7 days after becoming ill but they may have it in their stool before symptoms develop and Rotavirus can still be in their stool for up to 3 weeks after the beginning of their illness.

What is the treatment for diarrhea?

  • Children with mild to moderate diarrhea can be cared for at home with close supervision, special fluids, and your pediatricians advice.
  • Treatment consists of oral rehydration and early introduction of breast or formula feeding and regular foods before the diarrhea ends. This helps the intestines repair itself quicker and shortens the length of the illness.


  • To prevent or to treat a child for dehydration from gastroenteritis, lost fluids can be replaced using an oral rehydration solution, such as Pedialyte, Infalyte or Kaoelectrolyte (also available as popsicles), over the course of a few hours.
  • Start the rehydration process by giving your child 1 teaspoon (5 milliliters) of an oral rehydration solution every 1 – 2 minutes.
  • Unflavored or flavored oral rehydration solutions, such as Pedialyte, Infalyte or Kaoelectrolyte (also available as popsicles), replace water and salts lost during a bout of gastroenteritis
  • You can use a spoon, oral syringe or a medicine dropper.
  • You can slowly increase the amount of fluid you give every five to ten minutes.
  • Even children who are vomiting can usually be successfully rehydrated in this way because the small frequent sips get absorbed in between the vomiting episodes
  • After keeping these small amounts of oral rehydration solution down you can give 60 to 120 mL (2 to 4 ounces) oral rehydration solution for each episode of diarrhea or vomiting to a child weighing less than 10 kg (or 22 pounds), and 120 to 240 mL (4 to 8 ounces) to a child weighing more than 10 kg (or 22
  • Breastfed infants should continue to be breastfed while receiving oral rehydration solutions.
  • Although oral rehydration solutions are very effective in replacing electrolyte and fluid losses, they do not shorten the duration of diarrhea or lessen the volume of stool.Early refeeding, however, can reduce stool output.


  • For mild diarrhea, most children should continue to eat a normal diet, if he/she is not persistently vomiting, including formula or milk. Breastfeeding should continue while the illness runs its course.
  • Food can help the intestine absorb more water, which helps slow down the diarrhea.
  • The old advice to let the intestine “rest” after a bout with diarrhea is no longer recommended by the American Academy of Pediatrics.
  • For severe diarrhea, your pediatrician may suggest that you temporarily remove cow’s milk from your child’s diet and switch to a soy formula. Some children are not able to tolerate cows milk when they have diarrhea and their intestines need some time to heal.
  • After your child is rehydrated and tolerating the larger amounts of the oral rehydration solution you should resume your childs normal diet, which should include:*  lots of complex carbohydrates (such as rice, potatoes, and whole-grain breads and cereals), lean meats, yogurt, fruits and vegetables, as well as the childs usual milk source (breast milk or formula for infants and full-strength cows milk for older children).
  • The once favored “BRAT” diet (bananas, rice, applesauce, and toast) is no longer recommended for children.
  • Be sure to avoid fatty foods or foods high in sugars, such as juices, soft drinks, sports drinks and Kool-Aid. These beverages dont have the right mix of sugar and salts and can even make diarrhea worse.
  • Resuming an age-appropriate diet early is essential in supplying your child with necessary calories and nutrients and can even reduce the duration of gastroenteritis.
  • Over-the-counter medicines for diarrhea are not recommended for children. They have potentially dangerous side effects in kids.

When can my child return to daycare or school?

  • For gastroenteritis, it will depend on how quickly your child’s symptoms go away, especially their fever and diarrhea.
  • Each facility generally has its own rules, but most wont let children attend if they have a fever of more than 100.4 F, are vomiting or have diarrhea.

When should I call my pediatrician concerning diarrhea in my child?

  • You should call your doctor anytime your child’s diarrhea is not improving or worsening, including not drinking well and any signs of dehydration.
  • Call immediately for any signs or symptoms that may suggest a serious cause for the diarrhea as listed above.

How can gastroenteritis be prevented?

  • Frequent hand washing is the most important way to minimize the spread of infection. Click on how to prevent infection for more details.
  • In 1999, a vaccine for Rotavirus was taken off of the market because of several cases of intussusception, one form of intestinal blockage, that occurred after the vaccine was given.
  • A new vaccine against Rotavirus has been developed and the American Academy of Pediatrics now recommends routine vaccination for our young children.

The recommendation is as follows:

  • three doses of pentavalent rotavirus vaccine administered orally at 2, 4 and 6 months of age. The first dose should be given between 6 to 12 weeks of age; vaccination should not be initiated for infants older than 12 weeks of age. Subsequent doses should be administered at 4 to 10 week intervals and all three doses of vaccine should be administered by 32 weeks of age.