What is the treatment for traveller's diarrhoea?

Treatment of Traveller's Diarrhea

For mild traveller's diarrhea, use loperamide (4 mg loading dose, then 2 mg after each loose stool, maximum 16 mg/day) with oral rehydration; for moderate cases, azithromycin (single 1-gram dose or 500 mg daily for 3 days) is the preferred antibiotic, with loperamide as optional adjunctive therapy; for severe cases, azithromycin is mandatory with loperamide as adjunctive therapy only if non-bloody diarrhea. 1, 2

Severity-Based Treatment Algorithm

Mild Traveller's Diarrhea (Tolerable, Little Interference with Activities)

• Start with loperamide monotherapy: 4 mg loading dose (2 tablets), then 2 mg after each loose stool, maximum 16 mg per day 1, 2
• Ensure adequate hydration with oral rehydration solutions 2
• Critical safety point: Wait 1-2 hours between doses to avoid rebound constipation 1
• Escalate immediately to antibiotics if fever develops, moderate-to-severe abdominal pain occurs, or bloody diarrhea appears 1, 2

Important FDA safety warnings for loperamide: Avoid doses exceeding 16 mg/day due to risk of QT prolongation, Torsades de Pointes, cardiac arrest, and sudden death 3. Do not combine with QT-prolonging drugs (Class IA/III antiarrhythmics, certain antipsychotics, moxifloxacin, methadone) or in patients with cardiac conditions, electrolyte abnormalities, or congenital long QT syndrome 3.

Moderate Traveller's Diarrhea (Distressing, Forces Change in Activities)

• Azithromycin is the preferred first-line antibiotic with strong recommendation and high-level evidence 1, 2
• Dosing options: Single 1-gram dose (preferred for compliance) OR 500 mg daily for 3 days 2
• Loperamide can be added as adjunctive therapy using the same dosing as above, which reduces time to last unformed stool from 59 hours to approximately 1 hour when combined with antibiotics 2
• Alternative antibiotics include rifaximin (200 mg three times daily for 3 days) but only for non-invasive watery diarrhea 1, 2

Fluoroquinolones (ciprofloxacin 500 mg twice daily for 1-3 days or 750 mg single dose) may be used but are less preferred due to: 1, 2

• Resistance exceeding 85-90% for Campylobacter in Southeast Asia 2
• Increasing global resistance 2
• FDA warnings regarding disabling peripheral neuropathy, tendon rupture, CNS effects, and serious cardiac adverse reactions 4

Severe Traveller's Diarrhea (Incapacitating, Fever >38°C, Dysentery)

• Azithromycin is mandatory: 1-gram single dose or 500 mg daily for 3 days 1, 2
• Loperamide is relatively contraindicated in dysentery (bloody diarrhea) but can be used as adjunctive therapy in severe non-bloody diarrhea 1, 5
• Do not use loperamide when fever, bloody stools, or severe abdominal pain are present due to risk of toxic megacolon, particularly in patients with AIDS or infectious colitis 3

Regional Considerations

• In Southeast Asia and India: Azithromycin is clearly superior due to fluoroquinolone resistance exceeding 90% for Campylobacter 2
• In Mexico: Lower fluoroquinolone resistance rates exist, but azithromycin remains preferred for moderate-to-severe cases 2

When to Seek Medical Attention

• Microbiological testing is strongly recommended for: 2

  • Severe or persistent symptoms beyond 14 days
  • Bloody diarrhea
  • Failure of empiric antibiotic therapy within 24-36 hours
  • Immunocompromised patients
  • Fever with severe symptoms

• Persistent diarrhea beyond 14 days may indicate protozoal infections (Giardia, Cryptosporidium), post-infectious irritable bowel syndrome, or unmasking of inflammatory bowel disease 2, 6

Critical Safety Considerations

Loperamide contraindications and warnings: 3

• Contraindicated in children under 2 years due to respiratory depression and cardiac risks
• Stop immediately if constipation, abdominal distention, or ileus develop
• Use with extreme caution in patients with hepatic impairment
• Avoid in combination with CYP3A4 inhibitors (itraconazole), CYP2C8 inhibitors (gemfibrozil), or P-glycoprotein inhibitors (quinidine, ritonavir) as these increase loperamide exposure 2-13 fold 3

Fluoroquinolone warnings: 4

• Risk of disabling peripheral neuropathy (potentially irreversible)
• CNS effects including seizures, confusion, hallucinations, suicidal thoughts
• Discontinue immediately if neuropathy symptoms develop (pain, burning, tingling, numbness, weakness)
• Avoid in patients with CNS disorders or seizure history

Antimicrobial Resistance Concerns

• Increasing association between travel, antibiotic use, and acquisition of multidrug-resistant bacteria 2
• Antibiotic treatment should be reserved for moderate-to-severe cases to minimize resistance 2
• Single-dose regimens are preferred when possible for better compliance and reduced resistance pressure 2

Practical Implementation

• Travelers should carry loperamide for immediate use in mild cases 2
• Provide azithromycin for self-treatment of moderate-to-severe cases, particularly for Southeast Asia travel 2
• Counsel patients to discontinue loperamide and contact healthcare provider if no improvement within 48 hours, or if blood in stools, fever, or abdominal distention develop 3