Pediatric Gastroenteritis

Updated: Nov 26, 2018
Author: Randy P Prescilla, MD; Chief Editor: Russell W Steele, MD 



Although often considered a benign disease, acute gastroenteritis remains a major cause of morbidity and mortality in children around the world, accounting for 1.34 million deaths annually in children younger than 5 years, or roughly 15% of all child deaths.[1] As the disease severity depends on the degree of fluid loss, accurately assessing dehydration status remains a crucial step in preventing mortality. Luckily, most cases of dehydration in children can be accurately diagnosed by a careful clinical examination and treated with simple, cost-effective measures. Although dehydration technically refers to pure water loss and can be associated with euvolemic or even hypervolemic states in certain pediatric disorders, the term is used throughout this article in its more general sense to mean overall fluid or volume loss due to diarrhea.


Adequate fluid balance in humans depends on the secretion and reabsorption of fluid and electrolytes in the intestinal tract; diarrhea occurs when intestinal fluid output overwhelms the absorptive capacity of the gastrointestinal tract. The 2 primary mechanisms responsible for acute gastroenteritis are (1) damage to the villous brush border of the intestine, causing malabsorption of intestinal contents and leading to an osmotic diarrhea, and (2) the release of toxins that bind to specific enterocyte receptors and cause the release of chloride ions into the intestinal lumen, leading to secretory diarrhea.[2]

Even in severe diarrhea, however, various sodium-coupled solute co-transport mechanisms remain intact, allowing for the efficient reabsorption of salt and water. By providing a 1:1 proportion of sodium to glucose, classic oral rehydration solution (ORS) takes advantage of a specific sodium-glucose transporter (SGLT-1) to increase the reabsorption of sodium, which leads to the passive reabsorption of water. Rice and cereal-based ORS may also take advantage of sodium-amino acid transporters to increase reabsorption of fluid and electrolytes.[2]



United States

Children in the United States experience, on average, 1.3-2.3 episodes of diarrhea each year. Overall, acute gastroenteritis accounts for than 1.5 million outpatient visits, 220,000 hospitalizations, and direct costs of more than $2 billion each year in the United States alone.[3]

A study by Hullegie et al investigated the effects of first-year daycare attendance on acute gastroenteritis incidence and primary care contact rate up to age 6 years. The study found that first-year daycare attendance advances the timing of acute gastroenteritis infections, resulting in increased acute gastroenteritis disease burden in the first year and relative protection thereafter. The study also added that protection against acute gastroenteritis infection persists at least up to age 6 years.[4]


Worldwide, children younger than 5 years have an estimated 1.7 billion episodes of diarrhea each year, leading to 124 million clinic visits, 9 million hospitalizations, and 1.34 million deaths, with more than 98% of these deaths occurring in the developing world.[1, 5, 6, 7]

Although the prevalence of acute gastroenteritis in children has changed little over the past 4 decades, mortality has declined sharply, from 4.6 million in the 1970s to 3 million in the 1980s and 2.5 million in the 1990s.[8] One of the most important reasons for this decline has been the increasing international support for the use of oral rehydration solution (ORS) as the treatment of choice for acute diarrhea, with the proportion of diarrheal episodes treated with ORS rising from 15% in 1984 to 40% in 1993.[8]




The history and physical examination serve 2 vital functions: (1) differentiating gastroenteritis from other causes of vomiting and diarrhea in children and (2) estimating the degree of dehydration. In some cases, the history and physical examination can also aid in determining the type of pathogen responsible for the gastroenteritis, although only rarely will this affect management.


Determine the duration of diarrhea, the frequency and amount of stools, the time since the last episode of diarrhea, and the quality of stools. Frequent, watery stools are more consistent with viral gastroenteritis, while stools with blood or mucous are indicative of a bacterial pathogen. Similarly, a long duration of diarrhea (>14 days) is more consistent with a parasitic or noninfectious cause of diarrhea.


Determine the duration of vomiting, the amount and quality of vomitus (eg, food contents, blood, bile), and time since the last episode of vomiting. When symptoms of vomiting predominate, one should consider other diseases such as gastroesophageal reflux disease (GERD), diabetic ketoacidosis, pyloric stenosis, acute abdomen, or urinary tract infection.


Determine if there is an increase or decrease in the frequency of urination as measured by the number of wet diapers, time since last urination, color and concentration of urine, and presence of dysuria. Urine output may be difficult to determine with frequent watery stools.

Abdominal pain

Determine the location, quality, radiation, severity, and timing of pain, based on a report from the parents and/or child. In general, pain that precedes vomiting and diarrhea is more likely to be due to abdominal pathology other than gastroenteritis.

Signs of infection

Determine the presence of fever, chills, myalgias, rash, rhinorrhea, sore throat, cough, known immunocompromised status. These may indicate evidence of systemic infection or sepsis.

Appearance and behavior

Elements include weight loss, quality of feeding, amount and frequency of feeding, level of thirst, level of alertness, increased malaise, lethargy, or irritability, quality of crying, and presence or absence of tears with crying.


A history of recent antibiotic use increases the likelihood of Clostridium difficile infection.


History of travel to endemic areas may make prompt consideration of organisms that are relatively rare in the United States, such as parasitic diseases or cholera.


Elements of the physical examination are as follows:

  • General - Weight, ill appearance, level of alertness, lethargy, irritability

  • HEENT (head, ears, eyes, nose, and throat) - Presence or absence of tears, dry or moist mucous membranes, and whether the eyes appear sunken

  • Cardiovascular - Heart rate and quality of pulses

  • Respiratory - Rate and quality of respirations (deep, acidotic breathing suggests severe dehydration).

  • Abdomen - Abdominal tenderness, guarding and rebound, and bowel sounds; abdominal tenderness on examination, with or without guarding, should prompt consideration of diseases other than gastroenteritis

  • Back - Flank/costovertebral angle tenderness increase the likelihood of pyelonephritis

  • Rectal - Quality and color of stool, presence of gross blood or mucous

  • Extremities - Capillary refill time, warm or cool extremities

  • Skin - Abdominal rash may indicate typhoid fever (infection with Salmonella typhi), while jaundice might make viral or toxic hepatitis more likely; slow return of abdominal skin pinch suggests decreased skin turgor and dehydration, while a doughy feel to the skin may indicate hypernatremia


Identifying the specific etiologic agent responsible for the acute gastroenteritis rarely changes management. However, it may be helpful to differentiate between viral, bacterial, parasitic, and noninfectious causes of diarrhea.

By far, viruses remain the most common cause of acute gastroenteritis in children, both in the developed and developing world. Rotavirus represents the most important viral pathogen worldwide, responsible for 37% of diarrhea-related deaths in children younger than 5 years.[9] Rotavirus infection follows seasonal variation, with an increased incidence in winter and decreased incidence in summer months.

In the United States, routine rotavirus vaccination has led to a 60-75% reduction in pediatric rotavirus hospitalization since 2006.[10, 11] A 2014 retrospective analysis reported that implementation of rotavirus vaccines has reduced the diarrhea-related healthcare use in US children by as much as 94% in 2009–2010.[12, 13] With the continued decline of rotavirus-associated gastroenteritis, noroviruses (Norwalk-like viruses) have become the leading cause of medically attended acute gastroenteritis in children younger than 5 years in the United States, accounting for 14,000 hospitalizations, 281,000 emergency department visits, 627,000 outpatient visits, and more than $273 million in treatment costs each year.[14] Caliciviruses, astroviruses, and enteric adenoviruses make up the remainder of cases of viral gastroenteritis. Viral gastroenteritis typically presents with low-grade fever and vomiting followed by copious watery diarrhea(upto10-20bowelmovementsper day),with symptomspersisting for 3-8 days.[3]

In developed countries, bacterial pathogens account for a small portion, perhaps 2-10%, of all cases of pediatric gastroenteritis. In the United States, the most important pathogens, in order of prevalence, are Campylobacter, Salmonella, Shigella, and Enterohemorrhagic Escherichia coli (EHEC) species.[3] Relative to viral gastroenteritis, bacterial disease is more likely to be associated with high fevers, shaking chills, bloody bowel movements (dysentery), abdominal cramping, and fecal leukocytes.

In developing countries, Enterotoxigenic Ecoli (ETEC) remains the most important bacterial cause of acute gastroenteritis in children, followed by Campylobacter, Salmonella, and Shigella, while also causing the majority of traveler’s diarrhea in all age groups.[15] Unlike other bacterial causes of gastroenteritis, ETEC is unlikely to cause dysentery.

C difficile has emerged as an important cause of antibiotic-associated diarrhea in children. Any antibiotic can trigger infection with C difficile, although penicillins, cephalosporins, and clindamycin are the most likely causes.[3] Since 50% of neonates and young infants are colonized with C difficile, symptomatic disease is unlikely in children younger than 12 months.[3]

Parasites remain yet another source of gastroenteritis in young children, with Giardia and Cryptosporidium the most common causes in the United States. Parasitic gastroenteritis generally presents with watery stools but can be differentiated from viral gastroenteritis by a protracted course or history of travel to endemic areas.[3]



Differential Diagnoses



Laboratory Studies

The vast majority of children presenting with acute gastroenteritis do not require serum or urine tests, as they are unlikely to be helpful in determining the degree of dehydration. In a meta-analysis of 6 studies, only serum bicarbonate (greater or less than 17) had statistically significant positive and negative likelihood ratios for detecting moderate dehydration.[16]

Clinically significant electrolyte abnormalities are rare in children with moderate dehydration. Any child being treated with intravenous fluids for severe dehydration, however, should have baseline electrolytes, bicarbonate, and urea/creatinine values tested. Laboratory tests are also indicated in patients with moderate dehydration whose history and physical examination are inconsistent with straightforward gastroenteritis.

Fecal leukocytes and stool culture may be helpful in children presenting with dysentery. Children older than 12 months with a recent history of antibiotic use should have stool tested for C difficile toxins. Those with a history of prolonged watery diarrhea (>14 days) or travel to an endemic area should have stool sent for ova and parasite tests.

Any child with evidence of systemic infection should have a complete workup, including CBC count and blood cultures. If indicated, urine cultures, chest radiography, and/or lumbar puncture should be performed.

Imaging Studies

Abdominal films are not indicated in the management of acute gastroenteritis. If the clinician suspects a diagnosis other than acute gastroenteritis based on history and physical examination findings, appropriate imaging modalities should be pursued.

Other Tests

Workup of acute gastroenteritis should begin by using elements of the history and physical examination to determine the level of dehydration. Both the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) recommend using a simple dehydration scale to classify the total body water loss occurring with dehydration as minimal/none (< 3%), mild/moderate (3-9%), or severe (>10%) (see Table 1).[2] The World Health Organization (WHO) recommends a simpler system for use by both physicians and lay health workers, which classifies dehydration as none, some, or severe (see Table 2).

A meta-analysis of 13 separate studies looking at individual signs and symptoms of dehydration found that only abnormal capillary refill (>2 seconds), decreased skin turgor, and abnormal respiratory pattern (hyperpnea) had statistically and clinically significant positive and negative likelihood ratios for detecting dehydration in children.[16]

Several studies have found that combinations of clinical signs and symptoms may have better sensitivity and specificity for detecting dehydration in children than individual signs or symptoms.[16, 17, 18, 19, 20]

A study by Gorelick et al assessed the validity of a combination of 10 signs and symptoms similar to those recommended by the CDC. They found that the presence of 3 or more signs had a sensitivity of 0.87 and a specificity of 0.82 for detecting moderate dehydration.[18] The presence of 7 or more signs had a sensitivity of 0.82 and a specificity of 0.90 for detecting severe dehydration.

Parkin et al recently validated a an 8-point scale that assigns 0-2 points each to general appearance, sunken eyes, mucous membranes, and tears.[17] A score of 5-8 on this scale had a positive likelihood ratio of 5.2 and a negative likelihood ratio of 0.55 for the presence of moderate/severe dehydration in children with acute gastroenteritis.

Table 1. Assessment of Dehydration [2] (Open Table in a new window)

Symptom or Sign

No or Minimal Dehydration

Mild-to-Moderate Dehydration

Severe Dehydration

Mental status


Restless, irritable

Lethargic, unconscious


Drinks normally

Drinks eagerly

Drinks poorly

Heart rate


Normal to increased


Quality of pulses


Normal to decreased

Weak or not palpable



Normal or fast




Slightly sunken

Deeply sunken





Mouth and tongue




Skin fold

Instant recoil

Recoil < 2 seconds

Recoil >2 seconds

Capillary refill



Prolonged or minimal




Cold, mottled, cyanotic

Urine output




Table 2: Assessment of Dehydration [21] (Open Table in a new window)

Severe Dehydration

Two of the following signs:

  • Lethargic or unconscious

  • Sunken eyes

  • Not able to drink or drinking poorly

  • Skin pinch goes back very slowly

Some Dehydration

Two of the following signs:

  • Restless, irritable

  • Sunken eyes

  • Thirsty, drinks eagerly

  • Skin pinch goes back slowly

No Dehydration

Not enough of the above signs to classify as some or severe dehydration



Medical Care

Prehospital care

Children with acute gastroenteritis rarely require intravenous (IV) access. In those presenting with circulatory collapse due to severe dehydration or sepsis, IV access should be obtained and followed by an immediate 20-mL/kg bolus of normal saline.

Emergency department care

The American Academy of Pediatrics (AAP), the European Society of Pediatric Gastroenterology and Nutrition (ESPGAN), and the World Health Organization (WHO) all recommend oral rehydration solution (ORS) as the treatment of choice for children with mild-to-moderate gastroenteritis in both developed and developing countries, based on the results of dozens of randomized, controlled trials and several large meta-analyses.[2, 16, 22, 23]

One large meta-analysis of 16 trials including 1545 children with mild-to-moderate dehydration found that compared with IV rehydration, children treated with ORS had a significant reduction in length of hospital stay and fewer adverse events, including seizures and death.[24] The overall rate of ORS failure (percentage of children eventually requiring IV hydration) in studies comparing ORS with IV hydration was about 4%.[25]

Initial care in the emergency department should focus on correction of dehydration. The type and amount of fluid given should reflect the degree of dehydration in the child.

Minimal orno dehydration

No immediate treatment is required. If the child is breastfed, the mother should be encouraged to breastfeed more frequently than usual and for longer at each feed. If the child is not exclusively breastfed, then oral maintenance fluids (including clean water, soup, rice water, yogurt drink, or other culturally appropriate fluid) should be given at a rate of approximately 500 mL/day for children younger than 2 years, 1000 mL/day for children aged 2-10 years, and 2000 mL/day for children older than 10 years.

In addition, ongoing fluid losses should be replaced with 10 mL/kg body weight of additional ORS for each loose stool and 2 mL/kg body weight of additional ORS for each episode of emesis (both for breastfed and nonbreastfed children).

A study of 647 children in Canada by Freedman et al found that patients with mild gastroenteritis and minimal dehydration experienced fewer treatment failures when offered half-strength apple juice followed by their preferred drinks compared with children given a standard electrolyte maintenance solution.[26, 27]

Mild-to-moderate dehydration

Children should be given 50-100 mL/kg of ORS over a 2- to 4-hour period to replace their estimated fluid deficit, with additional ORS given to replace ongoing losses (10 mL/kg body weight for each stool and 2 mL/kg body weight for each episode of emesis). After the initial rehydration phase, patients may be transitioned to maintenance fluids as described above.

ORS should be given slowly by the parent using a teaspoon, syringe, or medicine dropper at the rate of 5 mL every 1-2 minutes. If tolerated by the patient, the rate of ORS delivery can be increased slowly over time.

For patients who do not tolerate ORS by mouth, nasogastric (NG) feeding is a safe and effective alternative. Multiple clinical trials have found NG rehydration to be as efficacious as IV rehydration, but more cost effective and with fewer adverse events.[24, 28]

Patients should be reassessed frequently by the clinician to ensure adequacy of oral intake and resolution of the various signs and symptoms of dehydration.

Severe d ehydration

Severe dehydration constitutes a medical emergency requiring immediate resuscitation with IV fluids. IV access should be obtained and patients should be administered a bolus of 20-30 mL/kg lactated Ringer (LR) or normal saline (NS) solution over 60 minutes. If pulse, perfusion, and/or mental status do not improve, a second bolus should be administered. After this, the patient should be given an infusion of 70 mL/kg LR or NS over 5 hours (children < 12 months) or 2.5 hours (older children). If no peripheral veins are available, an intraosseous line should be placed. Serum electrolytes, bicarbonate, urea/creatinine, and glucose levels should be tested.

Once resuscitation is complete and mental status returns to normal, rehydration should continue with ORS as described above, as it has been shown to decrease the rate of hyponatremia and hypernatremia when compared with IV rehydration.

Type of ORS

A large Cochrane meta-analysis confirmed several earlier studies showing that reduced-osmolarity ORS (osmolarity< 250 mmol/L) is associated with fewer treatment failures, lower stool output, and less frequent vomiting compared with standard-osmolarity ORS for patients with noncholera gastroenteritis.[29] Patients with cholera, however, appear to have higher rates of hyponatremia with reduced-osmolarity ORS compared with standard-osmolarity ORS, without any of the added benefits seen in patients with noncholera gastroenteritis.[30]

Multiple preparations of reduced-osmolarity ORS are available in the United States, including Pedialyte, Infalyte, and Naturalyte. Available formulations in Europe include Dioralyte and Diocalm Junior. In developing countries, clinicians can use WHO ORS sachets or a homemade solution of 3 g (1 tsp) salt and 18 g (6 tsp) sugar added to 1 liter of clean water.

New research suggests that polymer-based ORS, made from complex carbohydrates such as rice, wheat, or maize, may reduce stool output and length of diarrhea compared with glucose-based ORS.[31, 32] With these solutions, carbohydrates are slowly digested in the small intestine, releasing glucose to facilitate sodium uptake without adding a significant osmotic load to bowel contents. Although not widely available in the United States currently, polymer-based ORS may become the preferred solution for oral rehydration of children with diarrhea in the future.

Feeding andnutrition

In general, children with gastroenteritis should be returned to a normal diet as rapidly as possible. Early feeding reduces illness duration and improves nutritional outcome.

Breastfed infants should continue to breast feeding throughout the rehydration and maintenance phases of acute gastroenteritis. Formula-fed infants should restart feeding at full strength as soon as the rehydration phase is complete (ideally in 2-4 hours). Weaned children should restart their normal fluids and solids as soon as the rehydration phase is complete. Fatty foods and foods high in simple sugars should be avoided.

For the majority of infants, clinical trials have found no benefit of lactose-free formulas over lactose-containing formulas. Similarly, highly specific diets, such as the BRAT (bananas, rice, applesauce, and toast) diet, have not been shown to improve outcomes and may provide suboptimal nutrition for the patient.


Prophylaxis with Probiotics

Some meta-analyses have suggested that probiotics improve outcomes in children with acute gastroenteritis. A large placebo-controlled study in India showed that prophylaxis with a probiotic formula of L. plantarum in healthy newborns in the first 5 days of life led to a significant reduction in the rate of sepsis and lower respiratory tract infections in the first 2 months of life.[33] However, among preschool children with acute gastroenteritis who completed another study, those who received a 5-day course of L. rhamnosus did not have better outcomes than those in the placebo group.[34] In another multicenter study of children who presented to the emergency department with gastroenteritis, a 5-day course of a probiotic with L. rhamnosus + L. helveticus did not prevent the development of moderate-to-severe gastroenteritis.[35]



Medication Summary

The goals of pharmacotherapy are to reduce morbidity, prevent complications, and provide prophylaxis. Antidiarrheal (ie, kaolin-pectin) and antimotility agents (ie, loperamide) are contraindicated in the treatment of acute gastroenteritis in children because of their lack of benefit and increased risk of adverse effects, including ileus, drowsiness, and nausea.

Probiotics are live microbial feeding supplements commonly used in the treatment and prevention of acute diarrhea. Possible mechanisms of action include synthesis of antimicrobial substances, competition with pathogens for nutrients, modification of toxins, and stimulation of nonspecific immune responses to pathogens. Two large systematic reviews have found probiotics (especially Lactobacillus GG) to be effective in reducing the duration of diarrhea in children presenting with acute gastroenteritis.[36, 37] A recent meta-analysis found probiotics may be especially effective for the prevention of C difficile –associated diarrhea in patients receiving antibiotics.[38] As probiotic preparations vary widely, it is difficult to estimate the effectiveness of any single preparation.

A recent review of 24 published studies found zinc supplementation may be effective in reducing the duration of diarrhea in children older than 6 months in areas where zinc deficiency and moderate malnutrition is prevalent.[39] The World Health Organization (WHO) recommends zinc supplementation (10-20 mg/day for 10-14 days) for all children younger than 5 years with acute gastroenteritis, although little data exist to support this recommendation for children in developed countries.

The mainstay of therapy includes prevention with the rotavirus vaccine and treatment with antimicrobials and antiemetics.


Class Summary

In February 2006, the US Food and Drug Administration (FDA) approved the RotaTeq vaccine for the prevention of rotavirus gastroenteritis. The vaccine has been endorsed by the American Academy of Pediatrics (AAP).In April 2008, the FDA approved Rotarix, another oral vaccine, for the prevention of rotavirus gastroenteritis. The current recommendation is to administer 2 separate doses of Rotarix to patients aged 6-24 weeks. Rotarix was efficacious in a large study, which reported that Rotarix protected patients with severe rotavirus gastroenteritis and decreased the rate of severe diarrhea or gastroenteritis of any cause.[40] Recent large trials in both Latin America and Africa have also found Rotarix to be effective in decreasing diarrhea morbidity and mortality in children.[41, 42, 43]

Rotavirus vaccine (RotaTeq, Rotarix)

Currently, 2 orally administered live-virus vaccines are marketed in the United States. Each is indicated to prevent rotavirus gastroenteritis, a major cause of severe diarrhea in infants.

RotaTeq is a pentavalent vaccine that contains 5 live reassortant rotaviruses and is administered as a 3-dose regimen against G1, G2, G3, and G4 serotypes, the 4 most common rotavirus group A serotypes. It also contains attachment protein P1A (genotype P[8]).

Rotarix protects against rotavirus gastroenteritis caused by G1, G3, G4, and G9 strains and is administered as a 2-dose series in infants aged 6-24 weeks.

Clinical trials reported that the vaccines prevented 74-78% of all rotavirus gastroenteritis cases, nearly all severe rotavirus gastroenteritis cases, and nearly all hospitalizations due to rotavirus.


Class Summary

Since the majority of cases of acute gastroenteritis in developed and developing countries are due to viruses, antibiotics are generally not indicated. Even in cases (eg, dysentery) in which a bacterial pathogen is suspected, antibiotics may prolong the carrier state (Salmonella infection) or may increase the risk of developing hemolytic-uremic syndrome (enterohemorrhagic Escherichia coli infection).[44]

In patients with positive stool assays or high clinical suspicion for C difficile infection, the offending antibiotic should be stopped immediately. Metronidazole (30 mg/kg/day divided qid for 7 days) can be used as a first-line agent, with oral vancomycin reserved for resistant infections.[44]

Although generally not recommended for children younger than 8 years, tetracycline (50 mg/kg/day PO divided qid for 3 days) and doxycycline (6 mg/kg PO as a single dose) remain the treatments of choice for cholera. Alternative treatments with good efficacy include erythromycin and ciprofloxacin.[44]

For patients with ova and parasite testing that confirms infection with Giardia, metronidazole (35-50 mg/kg/day PO divided q8h) remains the drug of choice. Nitazoxanide oral suspension (age 1-3 y: 100 mg PO q12h for 3 days; age 4-11 y: 200 mg PO q12h for 3 days) is as effective as metronidazole and has the added benefit of treating other intestinal parasites, such as Cryptosporidium.

Metronidazole (Flagyl)

Metronidazole is recommended as the treatment of choice for mild-to-moderate cases of C difficile colitis. It provides effective therapy, with reported response rates from 95-100%. In vitro activity is bactericidal and dose dependent. Standard dosing has been shown to promote fecal concentrations capable of a 99.99% reduction of C difficile. IV metronidazole may be administered to those patients who cannot tolerate oral medications because of its potential to accumulate in the inflamed colon. The IV route is not as effective as the oral route.

Doxycycline (Bio-Tab, Doryx, Doxy)

Doxycycline is a broad-spectrum, synthetically derived bacteriostatic antibiotic in the tetracycline class. It is almost completely absorbed, concentrates in bile, and is excreted in urine and feces as a biologically active metabolite in high concentrations.

It inhibits protein synthesis and, thus, bacterial growth by binding to the 30S and possibly 50S ribosomal subunits of susceptible bacteria. It may block dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest.

It is the treatment of choice for cholera. It is not recommended for children younger than 8 years.

Nitazoxanide (Alinia)

Nitazoxanide inhibits growth of C parvum sporozoites and oocysts and G lamblia trophozoites. It elicits antiprotozoal activity by interference with the pyruvate: ferredoxin oxidoreductase (PFOR) enzyme-dependent electron transfer reaction, which is essential to anaerobic energy metabolism. It is available as an oral suspension (20 mg/mL).

Tetracycline (Sumycin)

Tetracycline treats gram-positive and gram-negative organisms, as well as mycoplasmal, chlamydial, and rickettsial infections. It inhibits bacterial protein synthesis by binding with 30S and possibly 50S ribosomal subunit(s). It is the treatment of choice for cholera. It is not recommended for children younger than 8 years.


Class Summary

A review of 7 randomized, controlled trials in children found that oral ondansetron reduced vomiting and the need for intravenous (IV) rehydration and hospital admission, IV ondansetron and metoclopramide reduced the number of episodes of vomiting and hospital admission, and dimenhydrinate suppository reduced the d uration of vomiting.[45, 46]

A previous large, prospective, randomized, double-blind trial compared a single dose of an orally disintegrating ondansetron tablet with placebo in children presenting to an emergency department with acute gastroenteritis.[47] This study also found that children treated with ondansetron were less likely to vomit and that they had greater oral intake, were less likely to require IV rehydration, and had a reduced length of stay in the emergency department compared with children treated with placebo.

Several smaller studies have also demonstrated ondansetron to be effective in children.[45, 48]

Ondansetron (Zofran)

Ondansetron is a selective 5-HT3-receptor antagonist that blocks serotonin both peripherally and centrally. This is an off-label indication for pediatrics. Caution is advised with IV administration because of reported QT prolongation with higher doses.

Metoclopramide (Reglan)

Metoclopramide blocks dopamine receptors in chemoreceptor trigger zone of CNS and sensitizes tissues to acetylcholine. This is an off-label indication for pediatrics. Use is limited because of its risk for tardive dyskinesia.

Dimenhydrinate (Dramamine)

Dimenhydrinate is an ethanolamine H1 antagonist containing diphenhydramine and 8-chloro-theophylline. Its pharmacological effects principally result from diphenhydramine moiety, and it has CNS depressant, anticholinergic, antiemetic, antihistamine, and local anesthetic effects.



Further Outpatient Care

Parents should be instructed to continue providing maintenance ORS fluids at home as needed. Breastfeeding and formula feeding should be continued for infants, and children should be encouraged to return to a regular diet as rapidly as possible.

Parents should be instructed to look for the various signs of dehydration outlined above, such as change in mental status, decreased urine output, sunken eyes, absence of tears, dry mucous membranes, and slow return of abdominal skin pinch.

Parents should seek medical attention if dehydration returns, oral intake is inadequate, or if their child develops worsening abdominal pain, fever greater than 101°F, or prolonged diarrhea lasting longer than 14 days.

Further Inpatient Care

Inpatient admission should be considered for all children with acute gastroenteritis in the following situations:

  • Signs of severe dehydration are present

  • Caregivers are unable to manage oral rehydration or provide adequate care at home

  • Substantial difficulties exist in administering oral rehydration solution (ORS), such as intractable vomiting or inadequate ORS intake

  • Treatment failure, such as worsening diarrhea or dehydration despite adequate ORS intake, occurs

  • Factors are present necessitating closer observation, such as young age, decreased mental status, or uncertainty of diagnosis

Children with mild-to-moderate dehydration, children younger than 6 months, or children with a high frequency of stools/vomits should be monitored in the emergency department for a minimum of 4-6 hours before discharge.


The US Advisory Committee on Immunization Practices and the American Academy of Pediatrics recommend routine vaccination of US infants with rotavirus vaccine to protect against rotavirus gastroenteritis.[10]

Patient Education

For excellent patient education resources, visit eMedicineHealth's Esophagus, Stomach, and Intestine Center. Also see the patient education article, Gastroenteritis.