1. Test for Helicobacter pylori. The test items include urease test, histology, bacterial culture, serology, and urea breath test. At least two positive results can be used to confirm the diagnosis.
2. To ensure that the research results are not artificially distorted, this trial is a randomized study. Random allocation (which means that the subjects will use the "random number table generated by a computer similar to the lottery" to determine the treatment group) accept one of the following schemes (1:1:1).

Helicobacter pylori (H.pylori) infect more than 50% of humans globally. This study were (1) to test whether the efficacies of 14-day PCAB-based high-dose dual therapy and 14-day PPI-based reverse hybrid therapy can achieve a higher eradication rate than 14-day PCAB-based triple therapy in the first-line treatment of H pylori infection, (2) to compare the eradication rates of 14-day PCAB-based and PPI-based bismuth quadruple therapies in the second-line treatment of H pylori infection, and (3) to examine the impacts of antibiotic resistance of H pylori as well as CYP3A4, CYP2C19 and IL-1B -511 genotypes of host on the eradication efficacies of anti-H pylori treatments.

Inclusion Criteria:

Subjects infected with Helicobacter pylori.

Exclusion Criteria:

1. Those who have ever received Helicobacter pylori sterilization treatment.
2. Those who are allergic to the drugs used in this research.
3. Those who have had stomach surgery.
4. Those with severe liver cirrhosis or uremia or malignant tumors.
5. Women who are pregnant or breastfeeding.