What antibiotics are recommended for treating gastroenteritis?

Antibiotics for Gastroenteritis

Antibiotics are generally NOT recommended for most cases of gastroenteritis as they provide minimal benefit and may increase risks of antibiotic resistance and adverse effects. 1

General Approach to Gastroenteritis Management

• The cornerstone of therapy for all patients with gastroenteritis is fluid and electrolyte replacement, not antibiotics 2
• Most cases of gastroenteritis are viral in origin and self-limited, requiring only supportive care 3
• Empiric antimicrobial therapy is not recommended for most people with acute watery diarrhea without recent international travel 1

When Antibiotics Should Be Considered

Special Populations Requiring Consideration for Antibiotics:

• Immunocompromised patients (especially those with HIV) 1, 2
• Young infants who appear ill 1
• Pregnant women with Salmonella gastroenteritis (due to risk of extraintestinal spread) 1, 2
• Patients with severe symptoms or signs of invasive disease 4, 5

Specific Pathogens That May Warrant Antibiotics:

1. Shigella infection:

   • Requires prompt antibiotic treatment 4, 6
   • First-line: Azithromycin 4, 6

2. Campylobacter infection:

   • Only for severe cases or early in the illness course 4, 6
   • Treatment reduces duration by approximately 1 day 1
   • First-line: Azithromycin 4, 6

3. Salmonella infection:

   • Most cases do not require antibiotics 1, 4
   • Treatment indicated for severe infection or in high-risk patients 4, 6
   • When treatment is chosen: Ciprofloxacin (750 mg twice daily for 14 days) for adults 1, 2
   • For children: Ceftriaxone or other appropriate alternatives 4

4. Clostridioides difficile infection:

   • Always requires antimicrobial therapy 3

5. Traveler's diarrhea:

   • Consider empiric treatment with fluoroquinolones (e.g., ciprofloxacin 500mg twice daily for 3-7 days) 1
   • Alternative for children/pregnant women: TMP-SMZ 1

Antibiotics to Avoid in Gastroenteritis

• STEC (Shiga toxin-producing E. coli) infections: Avoid fluoroquinolones, β-lactams, TMP-SMX, and metronidazole as they may increase risk of hemolytic uremic syndrome 1
• Ampicillin-sulbactam: Not recommended due to high rates of resistance among community-acquired E. coli 1
• Cefotetan and clindamycin: Not recommended due to increasing resistance among Bacteroides fragilis group 1

Important Caveats

• Antibiotics should be avoided in patients with persistent watery diarrhea lasting 14 days or more 1
• Asymptomatic contacts of people with acute or persistent watery diarrhea should not receive empiric or preventive therapy 1
• Antimotility agents (e.g., loperamide) should be discontinued if symptoms persist beyond 48 hours or if patients develop high fever or bloody stools 1
• Empirical treatment without bacteriological documentation should generally be avoided 4

Conclusion

The decision to use antibiotics for gastroenteritis should be based on the severity of illness, patient risk factors, and when possible, identification of the causative pathogen. For most immunocompetent patients with uncomplicated gastroenteritis, antibiotics provide minimal benefit and may cause harm through promoting resistance or adverse effects.