What is the treatment for infectious diarrhea?

Treatment of Infectious Diarrhea

The cornerstone of treatment for infectious diarrhea is rehydration therapy, with reduced osmolarity oral rehydration solution (ORS) recommended as first-line therapy for mild to moderate dehydration in all patients with acute diarrhea. 1

Rehydration Therapy

Mild to Moderate Dehydration

• Use reduced osmolarity oral rehydration solution (ORS) as first-line therapy 1, 2
• Continue ORS until clinical dehydration is corrected 1
• Nasogastric administration of ORS may be considered in patients who cannot tolerate oral intake 1

Severe Dehydration

• Administer isotonic intravenous fluids (lactated Ringer's or normal saline) 1, 2
• Continue IV rehydration until pulse, perfusion, and mental status normalize 1
• Transition to ORS once patient stabilizes 1
• Replace ongoing losses with ORS until diarrhea resolves 1

Nutritional Management

• Resume age-appropriate diet during or immediately after rehydration 1, 2
• Continue human milk feeding in infants throughout the diarrheal episode 1
• Avoid foods high in simple sugars and fats 2
• Consider lactose restriction if symptoms persist 2

Pharmacological Management

Antimicrobial Therapy

• In most people with acute watery diarrhea without recent international travel, empiric antimicrobial therapy is not recommended 1
• Antimicrobial treatment should be modified or discontinued when a causative organism is identified 1
• Consider antimicrobial therapy for:
  • Shigellosis: Azithromycin (first-line) 2
  • Campylobacter: Azithromycin (first-line) 2
  • Enterotoxigenic E. coli: TMP-SMX (if susceptible) or Azithromycin 2
  • Infectious diarrhea in immunocompromised patients 1, 3
  • Patients over 65 years with severe illness or sepsis 3

Antimotility Agents

• Antimotility drugs (e.g., loperamide) should not be given to children <18 years of age with acute diarrhea 1, 2
• Loperamide may be given to immunocompetent adults with acute watery diarrhea after adequate hydration 1, 2
• Avoid antimotility agents in patients with bloody diarrhea, fever, or suspected inflammatory diarrhea 1, 4
• Monitor for cardiac adverse reactions with loperamide, including QT prolongation 4

Adjunctive Therapies

• Antinausea and antiemetic agents (e.g., ondansetron) may be given to facilitate oral rehydration in children >4 years and adolescents with vomiting 1
• Probiotic preparations may reduce symptom severity and duration in immunocompetent patients 1
• Oral zinc supplementation is beneficial for children 6 months to 5 years in areas with high prevalence of zinc deficiency 1

Special Considerations

Bloody Diarrhea (Dysentery)

• Avoid antimicrobial therapy for STEC O157 and other STEC that produce Shiga toxin 2 1
• Consider appropriate antimicrobial therapy for confirmed shigellosis 1, 2

Persistent Diarrhea

• Avoid empiric treatment in people with persistent watery diarrhea lasting 14 days or more 1
• Focus on nutritional therapy and dietary modifications 5

Common Pitfalls to Avoid

1. Overuse of antibiotics in mild, likely viral cases 2
2. Inadequate fluid replacement leading to worsening dehydration 2
3. Premature use of antimotility agents in dysentery or inflammatory diarrhea 1, 2
4. Ignoring warning signs of severe disease requiring hospitalization (severe vomiting, persistent fever, abdominal distension, blood in stool) 2
5. Missing medication-induced diarrhea as a potential cause 2

Prevention and Control

• Advise appropriate infection prevention and control measures, especially proper hand hygiene 1, 2
• Asymptomatic contacts generally do not need treatment but should follow infection prevention measures 1

Remember that most cases of infectious diarrhea are self-limiting in immunocompetent individuals, and the primary goal of treatment is to prevent complications from dehydration while the infection resolves 3.