Almost all treatment recommendation for gastritis, duodenitis or peptic ulcer that has Helicobacter pylori, calls for 2 or 3 antibiotic at the same time, why is that ?

Why not use a single effective antibiotic?

  • because there's no single effective antibiotic .. you'd need to culture the bug to ascertain sensitivities before treatment. Simpler to use triple therapy. Commented Sep 30, 2017 at 21:57
  • 1
    @GrahamChiu This does not look like a comment but like something that might be put into an answer. With a bit more words and references, you know. Commented Oct 1, 2017 at 15:47

1 Answer 1


The aim of taking two antibiotics at the same is to prevent an overgrowth of the H. pylori strains that could be resistant to a single antibiotic. The antibiotic choice depends on the individual sensitivity to antibiotics.

Various treatment regimes have been proposed: Helicobacter pylori treatment: antibiotics or probiotics (Applied microbiology and biotechnology, 2018).

A standard treatment regime for the H. pylori infection of the stomach is a triple therapy for 10-14 days:

  1. a proton pump inhibitor, such as omeprazole (or ranitidine bismuth citrate)
  2. the antibiotic clarithromycin (or levofloxacin in case of resistance)
  3. the antibiotic amoxicillin (or metronidazole)

Probiotics taken along with triple therapy can increase the eradication rate.

In recent years, the effectiveness of the triple regime has fallen from 90% to <70% due to resistance of H. pylori to multiple antibiotics. The reported prevalence of resistance to:

  • metronidazole: ~10% in Japan, 17 to 44% in Europe and America, 50-100% in Africa
  • clarithromycin: 16% in Japan, 1.7 to 23.4% in Europe, 10.6 to 25% in North America

Suggested new therapies

Quadruple therapy (for areas with high incidence of clarithromycin resistance):

  1. a proton pump inhibitor
  2. bismuth citrate
  3. the antibiotic tetracycline
  4. the antibiotic metronidazole

The efficacy of the quadruple therapy in H. pylori eradication is similar than in triple therapy (~77%).

Sequential therapy uses the same drugs as the triple therapy but not at the same time (more effective in patients with the single clarithromycin-resistant strain; eradication rates were 80.9% for sequential therapy and 40.7% for standard triple therapy):

  • 5 days with a proton pump inhibitor plus amoxicillin followed by
  • 5 days of a proton pump inhibitor plus clarithromycin and amoxicillin

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.