1... Although H.PYLORI can be eradicated completely but it is not certain that just one course of antibiotics may treat up completely.Many times therapy is repeated is again.
If 2 therapies fail,then your doctor may wish to perform endoscopy
with culture to check the antibiotic susceptibilities./ sensitivities of the H.pylori strain you have.
After Knowing the antibiotic sensitivity profile of the H.pylori strain you have been infected with the doctor can then treat you with the most appropriate antibiotic combination that will get rid of the H.pylori you have.
2...once the germ is eradicated,your ulcer would heal completely.
3... To be sure,buy the medicine from a reputed shop and take a purchase bill.
4.. There are many combinations are available in the market and all are good.
Leave it to your doctor for the proper combination.