Helicobacter pylori is the cause of peptic ulcer, gastric cancer and gastric lymphoma. Diagnosis of H. pylori infection can be made using invasive and noninvasive tests. Invasive tests based on endoscopy, such as histology, are recommended when a gastric malignancy is suspected. Alternatively, noninvasive tests, such as the urea breath test and stool tests are useful for H. pylori diagnosis and follow-up. Triple therapy with either amoxicillin or metronidazole, clarithromycin and proton pump inhibitor given twice daily for 7-14 days is the recommended first-line treatment, after having checked the individual clarithromycin antimicrobial susceptibility. A triple therapy with levofloxacin, amoxicillin and proton pump inhibitor for 10-14 days should be used as second-line treatment, where the strains are susceptible to fluoroquinolone. Alternatively, bismuth-based quadruple therapy is recommended.