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Diarrhea in Children


Deborah M. Consolini

, MD, Thomas Jefferson University Hospital

Reviewed/Revised Nov 2022 | Modified Mar 2023
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Diarrhea is a very common problem in children (see also Diarrhea in adults Diarrhea in Adults Diarrhea is an increase in the volume, wateriness, or frequency of bowel movements. (See also Diarrhea in Children.) The frequency of bowel movements alone is not the defining feature of diarrhea... read more ). Diarrhea is frequent, loose, or watery bowel movements (BMs) that differ from a child’s normal pattern. Sometimes diarrhea contains blood or mucus. Identifying mild diarrhea may be difficult because in healthy children, the number and consistency of BMs vary with age and diet. For example, breastfed infants who are not yet receiving solid food often have frequent, loose stools that are considered normal. A sudden increase in number and looseness may indicate diarrhea in these infants. However, having watery stools for more than 24 hours is never normal.

Worldwide, diarrhea causes 1.5 to 2.5 million deaths a year. In the United States, diarrhea accounts for about 9% of hospitalizations for children under 5 years old.

Causes of Diarrhea in Children

Likely causes of diarrhea depend on whether it lasts less than 2 weeks (acute) or more than 2 weeks (chronic). Most cases of diarrhea are acute.

Common causes

Acute diarrhea is usually caused by

Certain antibiotics can alter the types and number of bacteria in the intestine. As a result, diarrhea can occur. Sometimes using antibiotics enables a particularly dangerous bacteria, Clostridioides difficile (formerly Clostridium difficile), to multiply. Clostridioides difficile releases toxins that can cause inflammation of the lining of the large intestine (colitis— see Clostridioides (formerly Clostridium) difficile–Induced Colitis Clostridioides (formerly Clostridium) difficile–Induced Colitis Clostridioides difficile (C. difficile)–induced colitis is an inflammation of the large intestine (colon) that results in diarrhea. The inflammation is caused by toxin produced... read more ).

Chronic diarrhea is usually caused by

Less common causes

Evaluation of Diarrhea in Children

Warning signs

Certain symptoms are cause for concern. They include

  • Signs of dehydration, such as decreased urination, lethargy or listlessness, crying without tears, extreme thirst, and a dry mouth

  • Ill appearance

  • High fever

  • Blood in stool

  • Pain in the abdomen and, when touched, extreme tenderness

  • Bleeding in the skin (seen as tiny reddish purple dots [petechiae] or splotches [purpura])

When to see a doctor

Children with any warning signs should be evaluated by a doctor right away, as should those who have had more than 3 or 4 episodes of diarrhea and are not drinking or are drinking very little.

If children have no warning signs and are drinking and urinating normally, the doctor should be called if diarrhea lasts 2 days or more or if there are more than 6 to 8 episodes of diarrhea a day. If diarrhea is mild, a doctor’s visit is unnecessary. Children with diarrhea for 14 days or more should be seen by a doctor.

What the doctor does

Doctors first ask questions about symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause and the tests that may need to be done ( see Table: Some Causes and Features of Diarrhea Some Causes and Features of Diarrhea Some Causes and Features of Diarrhea ).

Doctors ask what the BMs look like, how frequent they are, how long they last, and whether the child has other symptoms, such as fever, vomiting, or abdominal pain.

Doctors also ask about potential causes, such as diet, use of antibiotics, consumption of possibly contaminated food, recent contact with animals, and recent travel.

A physical examination is done, looking for symptoms of dehydration and disorders that can cause diarrhea. The abdomen is checked for swelling and tenderness. Doctors also evaluate the child's growth Physical Growth of Infants and Children Physical growth refers to an increase in body size (length or height and weight) and in the size of organs. From birth to about age 1 or 2 years, children grow rapidly. After this rapid infant... read more .



If diarrhea lasts less than 2 weeks and warning signs are not present, the cause is probably gastroenteritis due to a virus, and testing is usually unnecessary. However, if doctors suspect another cause, tests are done to check for it.

Tests are typically done when children have warning signs. If they have signs of dehydration, blood tests are done to measure levels of electrolytes (sodium, potassium, calcium, and other minerals necessary to maintain the fluid balance in the body). If other warning signs are present, tests may include a complete blood cell count, urine tests, examination and analysis of stool, abdominal x-rays, or a combination.

Treatment of Diarrhea in Children

Specific causes of diarrhea are treated. For example, if children have celiac disease, gluten is removed from their diet. Antibiotics that cause diarrhea are stopped if a doctor recommends it. Gastroenteritis due to a virus usually disappears without treatment.

Drugs to stop diarrhea, such as loperamide, are not recommended for infants and young children.


Because the main concern in children is dehydration, treatment is focused on rehydrating by giving fluids and electrolytes ( see also Dehydration in Children Dehydration in Children Dehydration is loss of water from the body, usually caused by vomiting and/or diarrhea. Dehydration occurs when there is significant loss of body water and, to varying amounts, electrolytes... read more ). Most children with diarrhea are successfully treated with fluids given by mouth (orally). Fluids are given by vein (intravenously) only if children are not drinking, are vomiting a lot, or are severely dehydrated. Oral rehydration solutions Treatment Dehydration is loss of water from the body, usually caused by vomiting and/or diarrhea. Dehydration occurs when there is significant loss of body water and, to varying amounts, electrolytes... read more that contain the right balance of carbohydrates and sodium are used. In the United States, these solutions are widely available without a prescription from pharmacies and most supermarkets. Sports drinks, sodas, juices, and similar drinks have too little sodium and too much carbohydrate and should not be used.

If children are also vomiting, small, frequent amounts of fluid are given at first. Typically, 1 teaspoon (5 milliliters) is given every 5 minutes. If children keep this amount down, the amount is gradually increased. If the child is not vomiting, the initial amount of fluid does not need to be limited. With patience and encouragement, most children can take enough fluid by mouth to avoid the need for intravenous fluid. However, children with severe dehydration may need intravenous fluids.


As soon as children have received sufficient fluids and are not vomiting, they should be given an age-appropriate diet. Infants may resume breast milk or formula.

In children with chronic diarrhea, the treatment depends on the cause, but providing and maintaining adequate nutrition and monitoring for possible vitamin or mineral deficiencies are most important.

Key Points

  • Diarrhea is common among children.

  • Gastroenteritis, usually due to a virus, is the most common cause.

  • Children should be evaluated by a doctor if they have any warning signs (such as signs of dehydration, severe abdominal pain, fever, or blood or pus in stool).

  • Testing is rarely necessary when diarrhea lasts less than 2 weeks.

  • Dehydration is likely if diarrhea is severe or lasts a long time.

  • Giving fluids by mouth effectively treats dehydration in most children.

  • Drugs to stop diarrhea, such as loperamide, are not recommended for infants and young children.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Anti-Diarrheal, Imodium A-D, Imodium A-D EZ Chews , K-Pek II
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