(1) a proton-pump inhibitor (PPI) plus clarithromycin and amoxicillin; (2) a PPI plus clarithromycin and metronidazole; (3) bismuth subsalicylate plus metronidazole and tetracycline.

Erythromycin is more effective than clarithromycin, however with much more side effects.

Antibiotic treatment of H. pylori infection is not without risk: pseudomembranous colitis, overgrowth of Candida albicans, which can result in vaginitis, gastrointestinal disturbances, or other complaints. Moreover, antibiotic treatment could lead to the overgrowth of antibiotic-resistant strains of H. pylori, making further attempts at eradication more difficult. Bismuth accumulates in certain tissues and has the potential to cause neurotoxicity.

Alternative therapy (effective in inhibition): vitamin C,poly-unsaturated fatty acid,lactobacilli(yogurt),garlic,berberine(Oregon grape),flavonoids.