Pediatric Gastroenteritis in Emergency Medicine Medication

Updated: Apr 18, 2023
  • Author: Adam C Levine, MD, MPH; Chief Editor: Kirsten A Bechtel, MD  more...
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Medication Summary

The rotavirus vaccine is used for prevention of enterovirus is part of the CDC recommended childhood vaccines. Antimicrobial agents may be necessary to treat specific infections. Examples and discussion of these follows below. 


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. Several studies have found probiotics to be effective in reducing the duration of diarrhea and stool frequency in children presenting with acute gastroenteritis. [65, 66, 67, 68]  However, two large randomized controlled trials conducted in the US and Canada found that among preschool children with acute gastroenteritis, those who received a 5-day course of Lactobacillus rhamnosus GG did not have improvement in severity or duration of symptoms. [69, 70]  As probiotic preparations vary widely, it is difficult to estimate the effectiveness of any single preparation. Given the current conflicting evidence, probiotics cannot be recommended for routine management of acute diarrhea in children.    


The World Health Organization recommends zinc supplementation (10-20 mg/day for 10-14 days) for all children younger than 5 years with acute gastroenteritis. According to one systematic review, little data exist to support this recommendation for children in high resource settings, children who are well-nourished (ie, at low risk for zinc deficiency), and children younger than 6 months of age. [71] In another systematic review, zinc shows effectiveness with moderate quality of evidence in low resource settings, where zinc deficiency and undernutrition remain prevalent. [72] Zinc is also inexpensive and cost-effective for use in low resource settings but can be associated with increased vomiting. [72]   

Antidiarrheal agents

Antidiarrheals (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.



Class Summary

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. In February 2006, the US Food and Drug Administration (FDA) approved the RotaTeq vaccine for prevention of rotavirus gastroenteritis. The American Academy of Pediatrics (AAP) has endorsed the vaccine and recommended that the vaccine be administered as an oral 3-dose series at 2, 4, and 6 months of age. [73]  RotaTeq is a pentavalent vaccine that contains 5 live reassortant rotaviruses and protects against G1, G2, G3, and G4 serotypes, the 4 most common rotavirus group A serotypes. It also contains attachment protein P1A (genotype P[8]).

In April 2008, the FDA approved Rotarix, another oral vaccine, for prevention of rotavirus gastroenteritis. The current AAP recommendation is to administer 2 separate doses of Rotarix to infants at 2 and 4 months of age. [73]  Rotarix protects against rotavirus gastroenteritis caused by G1, G3, G4, and G9 strains.

The AAP expressed no preference for either RotaTeq or Rotarix. The first dose of rotavirus vaccine should be administered before the child is 15 weeks of age. The minimum interval between doses of rotavirus vaccine is 4 weeks. All doses should be administered by 8 months. [73]  While ideally the same vaccine should be used for each dose, in a clinical setting where it is not possible to obtain a product, the AAP states that immunization should not be deferred, and a mixed vaccine schedule can be utilized. A 2016 randomized study supports this recommendation, concluding that mixed schedules for rotavirus vaccines are safe and effective compared to single vaccine schedules. [74, 75]  A 2019 case-control vaccine effectiveness study reported that implementation of rotavirus vaccines has reduced diarrhea-related healthcare use in US children by 86%. [76]

Vaccine efficacy is generally lower in countries with higher level of child mortality (ie, low- and middle-income countries). [75]  However, both vaccines are effective against rotavirus gastroenteritis across a range of mortality settings and different nations. In middle- and low-income countries, it is particularly important that patients receive the full schedule of vaccination. [75, 77, 78, 79, 80]  

Rotavirus oral vaccine, live (Rotarix, RotaTeq)

Live, attenuated oral vaccine indicated for immunization to prevent rotavirus gastroenteritis in infants and children. RotaTeq is administered as a 3-dose regimen, whereas Rotarix is a 2-dose regimen. 



Class Summary

Because most cases of acute gastroenteritis are due to viruses, antibiotics are generally not indicated. Even in cases (eg, dysentery) where a bacterial pathogen is suspected, antibiotics may prolong the carrier state (Salmonella) or may increase the risk of hemolytic uremic syndrome (enterohemorrhagic Escherichia coli). [81, 82]  However, antimicrobials are indicated for a few specific etiologies of diarrhea. 


Clostridium difficile

In patients with positive stool assays or high clinical suspicion for C difficile, the offending antibiotic should be stopped immediately. For non-severe episodes, either metronidazole or vancomycin is recommended, with insufficient evidence to recommend one over the other. For a first-occurrence severe episode, vancomycin is recommended and the addition of intravenous metronidazole is optional. For a recurring severe episode, rifaximin should follow vancomycin. [83]



Metronidazole and tinidazole are first-line drugs and have been found to have similar efficacies, with a cure rate of up to 90% of patients. Tinidazole has a similar regimen and fewer adverse effects. Albendazole and nitazoxanide are second-line drugs and might be difficult to obtain or not licensed in some countries. Paromomycin is the only second-line drug that can be used for pregnant women, and quinacrine (not available in the United States) is usually reserved for difficult cases because it has numerous adverse effects. [84]


Vibrio cholerae

The WHO recommends rehydration as the mainstay therapy for the full clinical spectrum of cholera cases. Those with mild to moderate symptoms can be treated successfully with prompt administration of oral rehydration solution (ORS) and in children by providing zinc in addition to ORS. Patients diagnosed with severe dehydration require administration of intravenous fluids, with ORS also administered as soon as oral intake is possible. Antibiotic use should be selective and target those patients most likely to benefit clinically. This includes suspected cholera patients hospitalized with severe dehydration and, regardless of degree of dehydration, those who exhibited high purging or failed the first 4-hour course of rehydration therapy or have comorbidities that pose elevated risk in cholera illness. Antibiotics with proven single-dose efficacy are highly preferred to multidose regimens. For children aged younger than 12 years, a single dose of doxycycline (2-4 mg/kg PO) is recommended. Alternative drug choices include single dose azithromycin (20 mg/kg PO; maximum 1 g) or single dose ciprofloxacin (20 mg/kg PO; maximum 1 g). Zinc supplementation should be given to all children aged 6 months to 5 years with diarrhea. [85]  


Shigella dysenteriae

For children, ciprofloxacin (15 mg/kg PO BID for 3 days) is the first-line antibiotic for treatment of Shigella. Pivmecillinam (20 mg/kg PO QID for 5 days; not available in the United States), ceftriaxone (50-100 mg/kg IM QD for 2-5 days), and azithromycin (6-20 mg/kg PO QD for 1-5 days) are also recommended; however, they should only be used when local strains of Shigella are known to be resistant to ciprofloxacin. When an effective antimicrobial is given, improvement should be evident within 48 hours, including fewer stools, less blood in the stools, reduced fever, and improved appetite. Failure to show such improvement may suggest possible antimicrobial resistance. Antibiotics that should not be used for treatment of infections with Shigella owing to its resistivity include ampicillin, chloramphenicol, co-trimoxazole, tetracycline, and nalidixic acid. Nitrofurans, aminoglycosides, first- and second-generation cephalosporins, and amoxicillin may be sensitive to Shigella in vitro but penetrate the intestinal mucosa poorly. [86]  

Vancomycin (Firvanq, Vancocin)

Indicated for Clostridium difficile-associated diarrhea. 

Metronidazole (Flagyl, Flagyl ER, Flagyl IV RTU)

Indicated for severe Clostridium difficile-associated diarrhea. Also indicted as first-line treatment of giardiasis. 

Rifaximin (Xifaxan)

Indicated for Clostridium difficile-associated diarrhea. 

Tinidazole (Tindamax)

Indicated as first-line treatment of giardiasis. 

Albendazole (Albenza)

Indicated as second-line treatment of giardiasis. 

Nitazoxanide (Alinia)

Indicated as second-line treatment of giardiasis. 


May be considered for off-label use to treat giardiasis. 


Indicated as single-dose treatment of Vibrio cholera.

Azithromycin (Zithromax, Zmax)

Indicated as single-dose treatment of Vibrio cholera. Also indicated for treatment of Shigella dysenteriae. 

Ciprofloxacin (Cipro, Cipro XR, ProQuin XR)

Indicated as single-dose treatment of Vibrio cholera. Also indicated as first-line treatment of Shigella dysenteriae. 


Indicated for treatment of Shigella dysenteriae



Class Summary

Vomiting is a common symptom of acute gastroenteritis; 75% of children with rotavirus infection reported at least one episode. [87]  A prospective, multicenter, double-blind randomized controlled trial (RCT) found that in children who continue to vomit after the first oral rehydration therapy (ORT) attempt, a single dose of the antiemetic ondansetron significantly improved the success of ORT, reduced the need for intravenous therapy, and reduced the number of patients with episodes of vomiting during an emergency department stay, compared with a placebo and the drug domperidone. [88]  Another RCT found that rotavirus-infected children treated with ondansetron had fewer diarrhea episodes and fewer days with clinical symptoms. [89]  A third RCT found that ondansetron was effective in reducing the emesis from gastroenteritis during administration of oral rehydration in the emergency department and in lowering the rates of intravenous fluid administration and hospital admission. [90]  Similarly, two RCTs (one in Pakistan and the other in India) found that administration of ondansetron in dehydrated children with acute gastroenteritis resulted in a reduction of intravenous use, faster rehydration, and fewer vomiting episodes. [91, 92]

There is limited evidence on the efficacy of other antiemetics, such as metoclopramide and dimenhydrinate. [93]  Although some studies have suggested that metoclopramide and dimenhydrinate are effective in reducing vomiting in children with acute gastroenteritis, they are believed to have more severe adverse effects than oral ondansetron. [94, 95]


May be consider a single oral dose for severe, acute vomiting associated with gastroenteritis.