Amoxicillin and metronidazole （400mg Q.D.S） based quadruple therapy had achieved a high cure rate in the rescue treatment of helicobacter pylori infection. This study aims to evaluate the efficacy and safety of the amoxicillin and metronidazole (400mg thrice a day) based triple therapy and the addition of bismuth in the naive patients with helicobacter pylori infection.

Inclusion Criteria:

• Participants with non-ulcer functional dyspepsia or peptic ulcer disease
• Ability and willingness to participate in the study and to sign and give informed consent
• Confirmed H. pylori infection and with no previous treatment experience

Exclusion Criteria:

• Less than 18 years old
• With previous gastric surgery
• Major systemic diseases
• Pregnancy or lactation
• Allergy to any of the study drugs Administration of antibiotics, bismuth, antisecretory drugs in 8 weeks prior to inclusion