H. Pylori Treatment: Regimens and Dosing
For treatment-naive H. pylori infection, use bismuth quadruple therapy for 14 days as first-line treatment, consisting of bismuth ~300mg four times daily, metronidazole 500mg three times daily, tetracycline 500mg four times daily, and a standard-dose PPI twice daily. 1, 2
First-Line Treatment Options
Preferred Regimen: Bismuth Quadruple Therapy (14 days)
- Bismuth subsalicylate: ~300mg four times daily (e.g., 2 Pepto-Bismol tablets QID)
- Tetracycline HCl: 500mg four times daily
- Metronidazole: 500mg three times daily
- PPI: Standard dose twice daily (pantoprazole 40mg, lansoprazole 30mg, omeprazole 20mg, esomeprazole 20mg, or rabeprazole 20mg)
Timing: Take bismuth 30 minutes before meals, antibiotics 30 minutes after meals, and PPI 30 minutes before meals and at bedtime 3
This regimen achieves >90% eradication rates in per-protocol analysis and remains effective regardless of local antibiotic resistance patterns 1, 2, 4.
Alternative First-Line Regimens (14 days each)
Rifabutin Triple Therapy (suitable empiric alternative):
- Rifabutin 150mg twice daily
- Amoxicillin 1g three times daily
- High-dose PPI (esomeprazole or rabeprazole 40mg) twice daily 1, 3, 2
Concomitant Therapy (only in areas with <15% clarithromycin resistance):
- Clarithromycin 500mg twice daily
- Amoxicillin 1g twice daily
- Metronidazole or tinidazole 500mg twice daily
- PPI twice daily 1
Critical Dosing Considerations
PPI Selection Matters
Use higher-potency PPIs when possible: Esomeprazole 20-40mg or rabeprazole 20-40mg twice daily are preferred over pantoprazole, as PPI potency significantly impacts eradication success, particularly with amoxicillin-containing regimens 3. Standard equivalencies: 40mg pantoprazole = 9mg omeprazole; 20mg esomeprazole = 32mg omeprazole; 20mg rabeprazole = 36mg omeprazole.
Duration is Non-Negotiable
All regimens must be given for 14 days to optimize eradication rates, as shorter durations consistently show inferior outcomes 2, 5. The 10-day regimen may only be considered for treatment-naive patients weighing <70kg 4.
Salvage Therapy After Treatment Failure
After First Treatment Failure
If bismuth quadruple therapy fails, use:
- Levofloxacin triple therapy (14 days): Levofloxacin 500mg once daily, amoxicillin 1g twice daily, PPI twice daily 1
- Rifabutin triple therapy if not used initially 1, 2
After Two Treatment Failures
Obtain antibiotic susceptibility testing before proceeding 1, 2. Do not use clarithromycin or levofloxacin-containing regimens empirically after multiple failures—only use if susceptibility is confirmed 1, 2.
Options after susceptibility testing include:
- High-dose dual therapy: Amoxicillin 2-3g daily in 3-4 divided doses with high-dose PPI twice daily for 14 days 1
- Rifabutin triple therapy (if not previously used)
- Repeat optimized bismuth quadruple therapy
Common Pitfalls to Avoid
Do NOT use standard triple therapy (PPI + clarithromycin + amoxicillin) empirically in North America due to >30% clarithromycin resistance rates 2, 6
Avoid levofloxacin empirically after treatment failure, as resistance exceeds 30% in many areas 2, 6
Do NOT prescribe probiotics as adjunctive therapy—they are of unproven benefit and should be considered experimental 1
Ensure proper PPI timing: 30 minutes before eating on an empty stomach, without concomitant antacids or H2-receptor antagonists 1, 3
Confirm patient adherence before declaring treatment failure and escalating therapy 1
Special Populations
Penicillin allergy: Use bismuth quadruple therapy or levofloxacin-based regimens (if local resistance <15%) 1
Elderly patients (≥75 years): Standard-dose bismuth quadruple therapy for 14 days is preferred over half-dose regimens, which show significantly lower eradication rates (74.6% vs 90%) 4
Drug interaction risk: Half-dose antibiotic regimens (tetracycline 500mg BID, metronidazole 375mg BID) for 14 days may be considered, achieving 89.7% eradication 4