Interventions A physician will be recruited so as to obtain the patients' demographic data and medical history. Using sealed envelopes, eligible patients will be randomized in two groups, with a research assistant assigning the therapies according to the treatment allocations kept in the envelopes. In the first group, patients will be assigned to a 10-day concomitant PAMC therapy (40mg esomeprazole twice daily, 500mg clarithromycin twice daily, 1gr amoxicillin twice daily, and 500mg metronidazole twice daily). In the second group, patients will be assigned to the same concomitant PAMC therapy for 14days. Each envelope will contain precise written instructions regarding the treatment schedule, dosing, and time of medication ingestion, while further instructions will be available, if needed, via the telephone.