What Is Diarrhea?

    Diarrhea is frequent soft or loose bowel movements (poop). Most kids have diarrhea from time to time. It usually doesn't last long and often gets better on its own.

    What Causes Diarrhea?

    Diarrhea is usually caused by an infection in the intestines. The germs that cause the infection are:

    • viruses (most common)
    • bacteria
    • parasites


    Viral gastroenteritis (often called the "stomach flu") is a common illness in children. It causes diarrhea and, often, nausea and vomiting. The symptoms usually last a few days, but kids (especially babies) who can't take enough liquids may become dehydrated.

    Rotavirus affects babies and young kids and can bring on watery diarrhea. Outbreaks are more common in the winter and early spring months, especially in childcare centers. The rotavirus vaccine can protect children from this illness.

    Enteroviruses, like coxsackievirus, also can cause diarrhea in kids, especially during the summer months.


    Many different types of bacteria can cause diarrhea, including E. coli, Salmonella, Campylobacter, and Shigella. These bacteria are often responsible for cases of "food poisoning," which can cause diarrhea and vomiting within a few hours after someone is infected.


    Parasitic infections that can cause diarrhea in children include giardiasis and cryptosporidiosis.

    What Else Can Cause Diarrhea?

    Kids can sometimes get diarrhea from:

    What Are the Signs & Symptoms of Diarrhea?

    Kids often get crampy belly pain first, followed by diarrhea that can last 3–5 days. Other symptoms may include:

    • fever
    • loss of appetite
    • nausea (an uncomfortable feeling before vomiting)
    • vomiting
    • weight loss
    • dehydration

    How Do Doctors Find the Cause of Diarrhea?

    Doctors will:

    • ask about what the child ate most recently, when symptoms began, and how often the diarrhea is happening
    • ask specific questions about the diarrhea: Is it watery? Is there blood in the poop? 
    • do an exam
    • sometimes, take a stool (poop) sample to send to a lab for analysis. This helps them find out which germ is causing the illness.

    How Is Diarrhea Treated?

    Viral diarrhea goes away on its own. Most kids with bacterial diarrhea need treatment with an antibiotic. Parasites always need treatment with anti-parasitic medicines.

    Kids who aren't vomiting or becoming dehydrated can continue eating and drinking or breastfeeding as usual. Continuing a regular diet may even shorten the diarrhea episode. You may want to serve smaller portions of food until the diarrhea ends.

    Don't give your child an over-the-counter anti-diarrhea medicine unless your doctor tells you to do so.

    What if My Child Is Dehydrated?

    For kids who show signs of mild dehydration, doctors recommend giving oral rehydration solutions (ORS). These are available in most grocery stores and drugstores without a prescription and replace body fluids as needed. Your doctor will tell you what kind to give, how much, and for how long.

    Kids should not be rehydrated with water alone because it doesn't contain the right mix of sodium, potassium, and other important minerals and nutrients.

    In some cases, kids with severe diarrhea may need to get IV fluids (given into a vein) at the hospital for a few hours to help treat the dehydration.

    How Can Diarrhea Be Prevented?

    It's almost impossible to prevent kids from ever getting diarrhea. But there are some ways to make it less likely:

    • Make sure kids wash their hands well and often, especially after using the toilet and before eating. Hand washing is the best way to prevent diarrheal infections that pass from person to person. Dirty hands carry germs into the body when kids bite their nails, suck their thumbs, eat with their fingers, or put any part of their hands into their mouths.
    • Keep bathroom surfaces like sinks and toilets clean.
    • Wash fruits and vegetables well before eating.
    • Clean kitchen counters and cooking utensils well after they've been in contact with raw meat, especially poultry.
    • Refrigerate meats as soon as possible after bringing them home from the store. Cook them until they're no longer pink. Refrigerate all leftovers as soon as possible.
    • Never drink from streams, springs, or lakes unless local health authorities have checked that the water is safe for drinking.
    • Avoid washing pet cages or bowls in the same sink that you use to prepare food. And try to keep pet feeding areas separate from family eating areas.

    When Should I Call the Doctor?

    Call your doctor if your child has diarrhea and is younger than 6 months old. Also call if your child has:

    • diarrhea many times a day or it lasts for more than 3 days
    • repeated vomiting and can't or won't drink fluids
    • severe belly pain
    • diarrhea that has blood in it

    Call the doctor right away if your child seems dehydrated. Signs include:

    • a dry or sticky mouth
    • few or no tears when crying
    • eyes that look sunken
    • in a baby, the soft spot (fontanelle) on top of the head looks sunken
    • peeing less or fewer wet diapers
    • drowsiness or dizziness
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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