What is the first line treatment for Helicobacter pylori (H. pylori) infection?

First-Line Treatment for Helicobacter pylori Infection

Bismuth quadruple therapy for 14 days is the preferred first-line treatment for H. pylori infection, especially in areas with high clarithromycin resistance (>15%). 1, 2, 3

Recommended First-Line Treatment Options

• Bismuth quadruple therapy (preferred): PPI (twice daily) + bismuth + metronidazole + tetracycline for 14 days 1, 2, 4
• In areas with low clarithromycin resistance (<15%), triple therapy using a PPI + clarithromycin + amoxicillin (or metronidazole) for 14 days may be considered 1, 2
• Concomitant (non-bismuth quadruple) therapy consisting of PPI + clarithromycin + amoxicillin + metronidazole for 14 days is an alternative first-line option 1

Rationale for Bismuth Quadruple Therapy

• Clarithromycin resistance is the primary reason for triple therapy failure, with global resistance rates increasing from 9% in 1998 to 17.6% in 2008-2009 1, 5
• Bismuth is valuable because bacterial resistance to this compound is extremely rare, making bismuth quadruple therapy effective even against strains resistant to metronidazole 2, 3
• In regions with clarithromycin resistance >15-20%, standard triple therapy should be abandoned due to unacceptably low eradication rates 1, 3

Optimizing Treatment Success

• High-dose PPI (twice daily) significantly increases eradication efficacy by 6-10% compared to standard doses 1, 3
• Extending treatment duration to 14 days improves eradication success by approximately 5% compared to shorter regimens 1, 2
• The use of probiotics as adjunctive treatment can help reduce side effects, particularly antibiotic-associated diarrhea 1, 3

FDA-Approved Regimens

• Triple therapy: Lansoprazole + amoxicillin + clarithromycin 6
• Dual therapy: Lansoprazole + amoxicillin (for patients allergic or intolerant to clarithromycin or when clarithromycin resistance is suspected) 6, 7

Second-Line Treatment Options

• After failure of a clarithromycin-containing therapy, either bismuth quadruple therapy (if not previously used) or levofloxacin-containing triple therapy is recommended 1, 2
• Levofloxacin-based triple therapy consists of a PPI twice daily, amoxicillin 1000 mg twice daily, and levofloxacin 500 mg once daily or 250 mg twice daily, for 14 days 1, 3

Common Pitfalls and Caveats

• Inadequate PPI dosing significantly reduces H. pylori treatment efficacy; always use high-dose (twice daily) PPI 1, 3
• Avoid repeating antibiotics to which the patient has been previously exposed, especially clarithromycin and levofloxacin 1, 2
• In patients allergic to penicillin, amoxicillin can be replaced with tetracycline 1
• After two failed eradication attempts, antimicrobial susceptibility testing should guide further treatment whenever possible 1, 3

Verification of Eradication

• Confirm eradication with urea breath test or monoclonal stool antigen test at least 4 weeks after completion of therapy and at least 2 weeks after PPI discontinuation 1, 3
• Serology should not be used to confirm eradication as antibodies may persist long after successful treatment 1, 2