This randomized controlled study aimed to evaluate whether adding bismuth to the standard first-line triple therapy could improve the eradication rate of Helicobacter pylori (H. pylori). A total of 162 patients with H. pylori infection were randomly assigned to either the 7-day triple therapy group (n = 81) or the bismuth plus triple therapy group (n = 81). The triple therapy (RAK) contained the twice-daily dosage of rabeprazole 20mg, amoxicillin 1g and clarithromycin 500mg. In the RBAK group, bismuth subcitrate 360 mg twice daily was added to the RAK regimen.

Once confirmed with H. pylori infection and having signed the informed consent, participants were randomly assigned to either the standard triple-therapy group (RAK: rabeprazole 20 mg, amoxicillin 1 g and clarithromycin 500 mg, all twice daily for 7 days) or the bismuth plus standard triple-therapy group (RBAK: rabeprazole 20 mg, bismuth subcitrate 360 mg, amoxicillin 1 g and clarithromycin 500 mg, all twice daily for 7 days). A computer-generated random number was chosen for randomization. The patients and physicians were not blinded to the therapy assigned.

After completion of H. pylori eradication therapy, participants were asked to come back for collection of the information on any adverse event of drug compliance. In order to avoid false negative results, they were also asked to have a 4-week proton pump inhibitor, antibiotic and bismuth washout period before further examination of H. pylori status. The second endoscopy with rapid urea test, histology and culture or 13 C-urea breath test (UBT) for those who refused endoscopic exams was carried out at the end of the washout period. Those who did not return to confirm their H. pylori status were deemed as treatment failure in intention-to-treat (ITT) analysis.

Inclusion Criteria:

1. male or non-pregnant female aged more than 20 y/r
2. H.pylori-infected
3. mental and legal ability to give a written informed consent

Exclusion Criteria:

1. allergy to any drug in the study
2. prior gastric surgery, severe concomitant diseases (e.g., decompensate liver cirrhosis, uremia, gastric cancer)
3. previous H. pylori eradication therapy
4. pregnancy or lactation.