What are the medications for gastroenteritis?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 10, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

For gastroenteritis, the primary treatment is supportive care focused on preventing dehydration rather than specific medications, with oral rehydration solutions and anti-diarrheal medications like loperamide used judiciously in adults, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines 1.

Key Considerations

  • Oral rehydration solutions like Pedialyte, Gatorade, or homemade solutions (1 teaspoon salt, 8 teaspoons sugar in 1 liter of water) should be consumed frequently in small amounts to prevent dehydration.
  • Anti-diarrheal medications such as loperamide (Imodium) at 2mg after each loose stool (maximum 8mg/day) can be used for adults but should be avoided in children and cases with high fever or bloody diarrhea, as per the guidelines 1.
  • For nausea and vomiting, ondansetron (Zofran) 4-8mg every 8 hours as needed may help, as suggested by the guidelines for the management of infectious diarrhea 1.
  • Most gastroenteritis cases are viral and self-limiting, typically resolving within 2-3 days, so antibiotics are generally not recommended unless bacterial infection is confirmed, as stated in the guidelines for travelers' diarrhea 1.

Important Exceptions

  • Antibiotics may be considered for severe travelers’ diarrhea, with azithromycin preferred, and fluoroquinolones or rifaximin used in specific cases, as recommended by the guidelines for travelers' diarrhea 1.
  • Loperamide may be used as adjunctive therapy for moderate to severe travelers’ diarrhea, and considered for use as monotherapy in moderate travelers’ diarrhea, as suggested by the guidelines 1.

Monitoring and Follow-up

  • Maintaining hydration is crucial as the body fights the infection, and medical attention should be sought if symptoms are severe, persistent beyond 3 days, or accompanied by high fever, bloody stools, or signs of dehydration.

From the FDA Drug Label

Loperamide hydrochloride is contraindicated in pediatric patients less than 2 years of age due to the risks of respiratory depression and serious cardiac adverse reactions The safety and effectiveness of loperamide hydrochloride in pediatric patients with chronic diarrhea have not been established The medication loperamide is not recommended for pediatric patients less than 2 years of age due to the risks of respiratory depression and serious cardiac adverse reactions.

  • The safety and effectiveness of loperamide for the treatment of gastroenteritis in pediatric patients have not been established, particularly for those less than 6 years of age, due to the risk of dehydration and paralytic ileus.
  • Loperamide should be used with special caution in pediatric patients due to their greater variability of response. 2

From the Research

Medication for Gastroenteritis

  • The primary goal of treating gastroenteritis is to prevent dehydration, and this can be achieved through oral rehydration therapy with a rehydration solution for patients with mild to moderate dehydration 3.
  • Ondansetron, an antiemetic, can be used to decrease vomiting and facilitate oral rehydration in children with gastroenteritis, although it may increase episodes of diarrhea 3, 4.
  • A study published in 2006 found that a single oral dose of ondansetron reduced vomiting and facilitated oral rehydration in children with gastroenteritis and dehydration 4.
  • Probiotics can also be used to shorten the course of diarrhea in patients with gastroenteritis 3.
  • For adolescents and adults with moderate to severe vomiting from acute gastroenteritis, a long-acting bimodal release oral ondansetron tablet has been shown to be an effective antiemetic, decreasing the need for intravenous access and emergency department care 5.
  • The treatment of gastroenteritis should focus on supportive care, including preventing dehydration and providing appropriate rehydration, as the vast majority of cases are self-limited and require only supportive care 6, 7.

Treatment Options

  • Oral rehydration therapy with a rehydration solution
  • Ondansetron to decrease vomiting and facilitate oral rehydration
  • Probiotics to shorten the course of diarrhea
  • Bimodal release ondansetron tablet for adolescents and adults with moderate to severe vomiting

Prevention

  • Good handwashing to reduce the incidence of acute gastroenteritis 3
  • Introduction of rotavirus vaccines to significantly reduce the incidence of rotavirus gastroenteritis 3

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.