Patient education: Acute diarrhea in children (Beyond the Basics)

DIARRHEA OVERVIEW — Diarrhea refers to the passage of loose or watery stools or an increased frequency of stools for the child and occurs at some point in the life of nearly every child. Diarrhea is not a disease but is a symptom of a number of illnesses. Although diarrhea is common and rarely serious, it is important to understand when to seek help. Diarrhea can lead to dehydration, which alters the child's natural balance of water, and to electrolyte (sodium, potassium, chloride) imbalance. It can be serious if not treated promptly.

This topic will review the major issues related to diarrhea in children. A brief summary is provided below. Diarrhea in adults is discussed separately. A topic that discusses nausea and vomiting in children is also available. (See 'Summary' below and "Patient education: Acute diarrhea in adults (Beyond the Basics)" and "Patient education: Nausea and vomiting in infants and children (Beyond the Basics)".)

DIARRHEA DEFINITION — The normal volume, frequency, and consistency of bowel movements varies with a child's age, weight, and diet, and the definition of diarrhea varies accordingly.

Frequency — It is normal for young infants to have up to 3 to 10 stools per day, although this varies depending upon the child's diet (breast milk versus formula; breastfed children usually have more frequent stools). Older infants, toddlers, and children normally have one to two bowel movements per day. Diarrhea is often defined as an increase in stool frequency to twice the usual number per day in infants or three or more loose or watery stools per day in older children. However, some specialists in gastrointestinal diseases may use a different definition.

Consistency and color — The consistency and color of a child's stool normally changes with age, which highlights the importance of knowing what is normal for your child. Young infants, especially those who are breastfeeding, usually have soft stools. Their stools may be yellow, green, or brown, and/or appear to contain seeds or small curds.

All children's stools can vary as a result of their diet. Development of stools that are runny, watery, or contain mucus is a significant change that should be monitored. The presence of visible blood or black stools is never normal and always requires medical attention. (See "Patient education: Blood in bowel movements (rectal bleeding) in babies and children (Beyond the Basics)".)

Duration — A prolonged history of diarrhea (one week or longer) is evaluated and treated differently than an acute case of diarrhea (lasting less than one week). The discussion below will focus on acute, rather than prolonged, diarrhea.

DIARRHEA CAUSES — The most common cause of acute diarrhea is a viral infection. Other causes include bacterial infections, side effects of antibiotics, and infections not related to the gastrointestinal (GI) system. In addition, there are many less common causes of diarrhea.

Viral, bacterial, and parasitic infections are all contagious, and parents/caretakers can assist in preventing spread of the infection. Children are considered contagious for as long as they have diarrhea. However, depending on the microorganism, some children can spread diarrhea even before they develop symptoms, and a minority, with specific types of infections, will continue to spread diarrhea pathogens for weeks or months after their symptoms resolve. Microorganisms causing diarrhea are spread from stools to hands and to mouth; hand washing and separating food-handling and feces disposal (eg, not changing diapers in the kitchen) are very important to preventing infection in household and other contacts. (See 'Preventing spread' below.)

Viral infection — Viral infection is the leading cause of diarrhea in children and is seen most commonly in the winter months in temperate climates, although it can occur year-round. Symptoms of viral infection can include fever (temperature higher than 38°C or 100.4°F), watery diarrhea, vomiting, abdominal cramps, lack of appetite, headache, and muscle aches.

Viral infection usually begins 12 hours to 5 days after exposure and resolves within three to seven days. No specific antiviral treatment is available for viral causes of diarrhea. Children with diarrhea from viral infections are best treated with supportive measures (oral rehydration solution; age-appropriate diet, limiting foods high in fat and simple sugars; and rest). Vomiting is the predominant feature of gastroenteritis caused by Norovirus, and medicines to prevent vomiting may be prescribed, with age-specific restrictions and precautions, to assist the child with oral rehydration. (See 'Home care of diarrhea' below.)

Bacterial infection — Bacterial infection is sometimes hard to distinguish from viral infection. Bacterial infections are more common in locations where there is unsafe drinking water and poor handling of sewage. Persistent high fever (higher than 40°C or 104°F) and diarrhea that is bloody or contains mucus are more common with bacterial diarrhea. Most children with bacterial infection do not require antibiotics and will improve with time and supportive measures. However, treatment may be necessary in certain situations.

Parasitic infection — Parasitic infections are more common in locations where there is unsafe drinking water and poor handling of sewage. Infection with a parasite is uncommon in developed countries but may be seen in children who have recently ingested contaminated water (including from baby pools) or who have traveled to or lived in resource-limited countries. Diarrhea from parasitic infections may last for weeks to months. (See "Patient education: Giardia (Beyond the Basics)" and "Patient education: Foodborne illness (food poisoning) (Beyond the Basics)".)

Antibiotic-associated diarrhea — A number of antibiotics can cause diarrhea in both children and adults. The diarrhea is usually mild and typically does not cause dehydration or weight loss. In most cases, antibiotics should not be stopped and the child's diet does not need to be changed. The diarrhea usually resolves one to two days after antibiotics are finished. Contact a health care provider if a child on antibiotics has diarrhea that is severe (see 'Frequency' above), contains blood, or does not resolve after the antibiotic is stopped. (See "Patient education: Antibiotic-associated diarrhea caused by Clostridioides difficile (Beyond the Basics)".)

DIARRHEA EVALUATION — The caregivers of many children with diarrhea appropriately do not seek medical evaluation, and others receive advice by telephone. The evaluation of diarrhea in children who do seek medical evaluation requires a careful review of medical history, a physical examination, and, infrequently, diagnostic testing. The clinician will perform a thorough examination to evaluate the general condition of your child because there are some infections unrelated to the bowels (such as an ear infection) that can cause diarrhea.

Many tests are available to diagnose the cause of diarrhea and to determine the severity of dehydration, although most children will not require testing.

HOME CARE OF DIARRHEA — The following are some simple recommendations to help care for children with diarrhea at home.

Dietary recommendations — There has been much confusion and folklore about optimal foods for children with diarrhea. Fortunately, a number of studies have examined recommendations that are proven to be effective and these recommendations have been consistent since the 1990s.

Children who are not dehydrated should continue to eat a regular diet, and infants who are breastfeeding should continue to do so unless the caregivers are told otherwise by their clinician. Children who are dehydrated require rehydration (replacement of lost fluid), and suitable oral rehydration solutions are the most physiologic. After being rehydrated, even the most severely affected children will be able to resume a normal diet. (See 'Oral rehydration therapy' below.)

Specific suggestions for children who are not dehydrated and are tolerating a regular diet include the following:

●Most children with diarrhea tolerate full-strength cow milk products. It is not necessary to dilute or avoid milk products, except in children with known allergies to cow milk.

●Recommended foods include a combination of complex carbohydrates (rice, wheat, potatoes, bread), lean meats, yogurt, fruits, and vegetables. High-fat foods are more difficult to absorb and should be avoided.

●The unnecessary restriction of a child's diet to clear liquids or the BRAT diet alone (bananas, rice, applesauce, toast) results in inadequate intake of nutrients (calories and/or protein). Giving only clear liquids for several days can actually prolong diarrhea (called "starvation stools").

●Sports drinks (sample brand name: Gatorade) should be avoided because they have too much sugar and have inappropriate electrolyte levels for the child with diarrhea. If fruit juice is to be given, we suggest starting with half-strength apple juice (apple juice mixed with an equal amount of water) and then letting the child drink whatever they prefer.

●Food should be provided in smaller, more frequent volumes to reduce the risk of vomiting.

Monitoring for dehydration — Mild dehydration is common in children with diarrhea. Signs and symptoms of mild dehydration include a slightly dry mouth, increased thirst, and slightly decreased urine output (one wet diaper or void in six hours). Common features of moderate or severe dehydration include markedly decreased urination (less than one wet diaper or void in six hours), lack of tears when crying, dry mouth, and sunken eyes (table 1).

Oral rehydration therapy — Oral rehydration therapy (ORT) was developed as a safer, less expensive, and easier alternative to intravenous fluids for children with mild to moderate dehydration. Oral rehydration solution (ORS) contains glucose (a sugar) and electrolytes (sodium, potassium, chloride) in a precise proportion to best replace water and electrolytes that are lost in children with vomiting and diarrhea. Various rehydration solutions are available. Caregivers should check with a health care provider to determine which solution is preferred. A child who is moderately or severely dehydrated needs to be evaluated by a health care provider. If a child refuses to accept ORS because of vomiting and/or becomes moderately to severely dehydrated (table 1), lethargic, or exhibits other features, the child requires professional evaluation and treatment, which may include intravenous rehydration.

ORT does not cure diarrhea, but it does treat the dehydration that often accompanies it. ORS can be purchased at most grocery stores and pharmacies in the United States without a prescription. A few widely available brands include Pedialyte, Enfalyte, and Rehydralyte, although generic brands are equally effective (table 2). Gelatin, tea, rice water, fruit juice, soda, energy drinks, and other beverages are not recommended for use as ORT in children with diarrhea and signs of dehydration (table 1). Some of these beverages can make diarrhea worse. Caregivers should not try to prepare ORS recipes at home because the formulas must be exact.

ORS may be given at home to a child who is mildly to moderately dehydrated, refusing to eat a normal diet, or has repeated vomiting and/or diarrhea even if not dehydrated. If needed, ORS can be given in frequent, small amounts by oral syringe, spoon, bottle, or cup over three to four hours. The aim is to replace the fluid the child may have already lost and/or will continue to lose because of ongoing vomiting and diarrhea. A doctor or nurse may provide specific instructions for oral rehydration to their patients. One method is described below:

●Caregivers should first measure out the total amount to be given with a standardized medicine syringe or measuring cup or spoon, rather than a regular cup or spoon.

●The recommended amount of ORS depends on the child's body weight, as shown in the table (table 3). This is approximately 1 cup (8 ounces) of ORS for every 10 pounds of body weight (or 500 mL per 10 kg). The total amount should be given gradually, spread out over approximately four hours.

●The fluid can be given by teaspoonfuls or oral syringe (approximately equal to 5 milliliters each) as frequently as every one to two minutes, or as tolerated.

●After the total amount has been given, a normal diet can be resumed if the child is willing to eat.

A child who refuses to drink or vomits immediately after drinking ORS should be monitored closely for worsening dehydration. (See 'Monitoring for dehydration' above.)

Medications — Medications such as antibiotics and antidiarrheal agents are generally not necessary and can be harmful for infants or children with diarrhea. Rarely, antibiotics may be used in cases of bacterial infection when a specific cause of the diarrhea has been found or is strongly suspected, particularly after recent travel. The doctor or nurse will evaluate the diarrheal episode to determine if antibiotics are necessary. Inappropriate use of antibiotics will not improve diarrhea. Furthermore, antibiotics can cause side effects and lead to development of antibiotic resistance.

Medications that prevent vomiting (antiemetics) generally are not necessary for children with acute diarrhea. However, an antiemetic that requires a prescription (ondansetron; sample brand names: Zofran, Zuplenz) may be helpful for children with dehydration and persistent vomiting that interferes with ORT. The doctor or nurse will evaluate your child to determine if ondansetron may be helpful.

Antidiarrheal agents (including those with sample brand names: Imodium, Pepto-Bismol, and Kaopectate) are not recommended for infants or children, since the benefits do not outweigh the risks. Loperamide (sample brand name: Imodium) should not be used because it can worsen some types of diarrhea. One risk of using an antidiarrheal agent is that it could mask worsening symptoms and delay treatment.

Probiotics — Although some studies suggest that "healthy" bacteria (probiotics) may reduce the duration of diarrhea by approximately 12 to 24 hours, more rigorous trials indicate that they do not make much of a difference [1,2]. Although probiotics are not contraindicated, their overall benefit is either small or nonexistent, and they can be expensive.

PREVENTING SPREAD — Caregivers of children who have diarrhea should be cautious to avoid spreading infection to themselves, their family, and friends. Care with hand washing, diapering, and keeping sick children out of school or day care until the diarrhea is gone are a few ways to limit the number of people exposed to the infection.

Hand washing is an essential and very effective way to prevent the spread of infection. Hands should ideally be wet with water and plain or antimicrobial soap and rubbed together for 15 to 30 seconds. Special attention should be paid to the fingernails, between the fingers, and the wrists. Hands should be rinsed thoroughly and dried with a single-use towel.

Alcohol-based hand rubs are a good alternative for disinfecting hands if a sink is not available However, alcohol-based hand rubs do not prevent all types of diarrhea (eg, Norovirus, Clostridioides difficile). Hand rubs should be spread over the entire surface of hands, fingers, and wrists until dry, and may be used several times. Hand rubs are available as a liquid or wipe in small, portable sizes that are easy to carry in a pocket or handbag. When a sink is available, visibly soiled hands should be washed with soap and water.

Hands should be cleaned after changing a diaper or touching any soiled item. They should also be washed before and after preparing food and eating, after going to the bathroom, after handling garbage or dirty laundry, after touching animals or pets, and after blowing the nose or sneezing.

Children who have diarrhea should not swim in swimming pools. Those who are not toilet trained should avoid swimming in swimming pools for one week after the diarrhea has recovered.

WHEN TO SEEK HELP FOR DIARRHEA — The following is a list of signs and symptoms that are worrisome and require immediate medical attention:

●Bloody diarrhea

●Refusal to eat or drink anything for more than a few hours in infants and for more than eight hours in children

●Moderate to severe dehydration

●Abdominal pain that persists, is severe, or occurs intermittently (either with a sudden onset or with marked discomfort)

●Behavior changes, including marked irritability, lethargy, or decreased responsiveness

●Intense, repeated vomiting

SUMMARY

●Most episodes of acute diarrhea resolve on their own. However, immediate medical attention should be sought for children who have any of the following: bloody diarrhea; signs of moderate to severe dehydration; refusing to eat or drink anything; abdominal pain that persists, is severe, or occurs intermittently (either with a sudden onset or with marked discomfort); behavior changes, including marked irritability, lethargy, or decreased responsiveness; or intense repeated vomiting. (See 'When to seek help for diarrhea' above.)

●The most common cause of acute diarrhea is a viral infection. Other causes include bacterial infections, side effects of antibiotics, and body-wide infections not related to the gastrointestinal (GI) system. In addition, there are many less common causes of diarrhea. (See 'Diarrhea causes' above.)

●Children who are not dehydrated should continue to eat their regular diet. Children who are dehydrated should be rehydrated, after which they can resume their normal diet (possibly with some modifications). Children who are breastfeeding should continue to do so unless told otherwise by their clinician. (See 'Dietary recommendations' above.)

●Oral rehydration therapy (ORT) may be given at home to a child who is mildly dehydrated, refusing to eat a normal diet, or has repeated vomiting and/or diarrhea even if not dehydrated. Common signs and symptoms of dehydration include decreased urination (less than one wet diaper or void in six hours), lack of tears when crying, dry mouth, sunken eyes, and weight loss. ORT can be purchased at most grocery stores and pharmacies in the United States without a prescription. (See 'Oral rehydration therapy' above.)

●Medications such as antibiotics, antidiarrheal agents, and medications that prevent vomiting are generally not recommended for infants or children with diarrhea. (See 'Medications' above.)

●Caregivers of children who have diarrhea should be cautious to avoid spreading infection to themselves, their family, friends, and others. Care with hand washing, diapering, and keeping sick children out of school or day care are a few ways to limit the number of persons exposed to infectious microorganisms. (See 'Preventing spread' above.)

WHERE TO GET MORE INFORMATION — Your child's health care provider is the best source of information for questions and concerns related to your child's medical problem.

This article will be updated as needed on our website (www.uptodate.com/patients). Related topics for patients and caregivers, as well as selected articles written for health care professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Diarrhea in children (The Basics)
Patient education: Diarrhea in teens and adults (The Basics)
Patient education: Bloody stools in children (The Basics)
Patient education: Food poisoning (The Basics)
Patient education: Lactose intolerance (The Basics)
Patient education: C. difficile infection (The Basics)
Patient education: Giving your child over-the-counter medicines (The Basics)
Patient education: Dehydration in children (The Basics)
Patient education: Cryptosporidiosis (The Basics)
Patient education: Salmonella infection (The Basics)
Patient education: E. coli diarrhea (The Basics)
Patient education: Campylobacter infection (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Acute diarrhea in adults (Beyond the Basics)
Patient education: Nausea and vomiting in infants and children (Beyond the Basics)
Patient education: Blood in bowel movements (rectal bleeding) in babies and children (Beyond the Basics)
Patient education: Giardia (Beyond the Basics)
Patient education: Foodborne illness (food poisoning) (Beyond the Basics)
Patient education: Antibiotic-associated diarrhea caused by Clostridioides difficile (Beyond the Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Approach to chronic diarrhea in children >6 months in resource-abundant settings
Shiga toxin-producing Escherichia coli: Clinical manifestations, diagnosis, and treatment
Clinical manifestations and diagnosis of rotavirus infection
Norovirus
Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis
Diagnostic approach to diarrhea in children in resource-abundant settings
Lactose intolerance and malabsorption: Clinical manifestations, diagnosis, and management
Oral rehydration therapy
Pathogenesis of acute diarrhea in children
Persistent diarrhea in children in resource-limited settings
Acute viral gastroenteritis in children in resource-abundant countries: Management and prevention
Probiotics for gastrointestinal diseases
Shigella infection: Epidemiology, clinical manifestations, and diagnosis
Causes of acute infectious diarrhea and other foodborne illnesses in resource-abundant settings

The following organizations also provide reliable health information.

●National Library of Medicine

(www.medlineplus.gov/healthtopics.html)

●The Centers for Disease Control and Prevention

(www.cdc.gov)

●National Institute of Diabetes and Digestive and Kidney Diseases

(www.niddk.nih.gov)

●The American Academy of Pediatrics

(www.aap.org)

[1-8]

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges David O Matson, MD, PhD, who contributed to earlier versions of this topic review.