For people who test positive for H. pylori the following regimens should be taken for 7 days

Take into account previous exposure to clarithromycin, metronidazole or a quinolone, do not use if used in the past year for any infection.

Always give a formulary choice proton pump inhibitor (See section 1.3.5 Proton pump inhibitors (PPI)) every 12 hours

1st line treatment

• Formulary choice proton pump inhibitor every 12 hours, plus
• Amoxicillin 1g every 12 hours and metronidazole 400mg every 12 hours

or

• Amoxicillin 1g every 12 hours and clarithromycin 500mg every 12 hours

Penicillin allergy

• Formulary choice proton pump inhibitor every 12 hours, plus
• Clarithromycin 500mg every 12 hours and metronidazole 400mg every 12 hours

See NICE CG184: Gastro-oesophageal reflux disease and dyspepsia in adults: investigation and management (November 2014) for people allergic to penicillin and who have previous exposure to clarithromycin

2nd line treatment

If people are still symptomatic after first-line treatment:

• Formulary choice proton pump inhibitor every 12 hours, plus
• Amoxicillin 1g every 12 hours, plus
• Metronidazole 400mg every 12 hours or clarithromycin 500mg every 12 hours, whichever was not used first-line

If the above treatments have failed, will not work due to resistance, or are unsafe to use in an individual patient, or penicillin allergic:

• Formulary choice proton pump inhibitor every 12 hours, plus
• Metronidazole 400mg every 12 hours, plus
• Levofloxacin 250-500mg every 12 hours (unlicensed)
  • Systemic fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate (See MHRA Drug Safety Updates below)
  • Patients should be advised to stop treatment at the first signs of a serious adverse reaction, such as tendinitis or tendon rupture, muscle pain, muscle weakness, joint pain, joint, feet, or abdomen swelling, peripheral neuropathy, rapid onset of shortness of breath, new-onset of heart palpitations, and central nervous system effects: including new or worsening depression or psychosis, and to seek immediate medical attention.

Drug Safety Updates for Levofloxacin (refer to 5.1.12 Quinolones for further details).

• MHRA Drug Safety Update (November 2018): Systemic and inhaled fluoroquinolones: small increased risk of aortic aneurysm and dissection; advice for prescribing in high-risk patients.
• MHRA Drug Safety Update (December 2020): Systemic and inhaled fluoroquinolones: small risk of heart valve regurgitation; consider other therapeutic options first in patients at risk.
• MHRA Drug Safety Update (September 2023): Fluoroquinolone antibiotics: suicidal thoughts and behaviour.
• MHRA Drug Safety Update (January 2024): Fluoroquinolone antibiotics: must now only be prescribed when other commonly recommended antibiotics are inappropriate.

See NICE CG184 for people who are penicillin allergic and have prior quinolone exposure

See NICE CG184 for people who have previous exposure to clarithromycin and metronidazole.

Consider referral to a specialist service, people with H. pylori that has not responded to second-line eradication therapy.

PPI therapy should only be continued after H pylori eradication in the case of active peptic ulceration. Continue once daily PPI therapy for one month for duodenal ulcers and two months for gastric ulcers.