AIM: To compare a lansoprazole-based triple versus quadruple therapy for Helicobacter pylori (H pylori) eradication with emphasis on side effect prof ile,patient compliance and eradication rate at a rural district general hospital in Wales,United Kingdom. METHODS: One hundred one patients with H pylori infection were included in the study. Patients were randomised to receive triple therapy comprising of lansoprazole 30 mg,amoxycillin 1 g,clarithromycin 500 mg,all b.d. (LAC),or quadruple therapy comprising of lansoprazole 30 mg b.d.,metronidazole 500 mg t.d.s.,bismuth subcitrate 240 mg b.d.,and tetracycline chloride 500 mg q.d.s. (LMBT). Cure was defi ned as a negative 13C urea breath test 2 mo after treatment. RESULTS: Seven patients were withdrawn after randomisation. Fifty patients were assigned to LAC group and 44 to LMBT group. The intention-to-treat cure rates were 92% and 91%,whereas the per-protocol cure rates were 92% and 97%,respectively. Side effects were common,with 56% experiencingmoderate to severe symptoms in the LAC group and 59% in the LMBT group. Symptoms of vomiting,diarrhoea and black stools were significantly more common in the LMBT group. Patient compliance was 100% for triple therapy and 86% for quadruple therapy (P < 0.01). One-third of patients in both groups were still taking acid-reducing medications at six-month follow-up. CONCLUSION: One-week triple and quadruple therapies have similar intention-to-treat eradication rates. Certain side effects are more common with quadruple therapy,which can compromise patient compliance. Patient education or modifi cations to the regimen are alternative options to improve compliance of the quadruple regimen. AIM: To compare a lansoprazole-based triple versus quadruple therapy for Helicobacter pylori (H pylori) eradication with emphasis on side effect prof ile, patient compliance and eradication rate at a rural district general hospital in Wales, United Kingdom. METHODS: One hundred one Patients with H pylori infection were included in the study. Patients were randomized to receive triple therapy comprising of lansoprazole 30 mg, amoxycillin 1 g, clarithromycin 500 mg, all bd (LAC), or quadruple therapy comprising of lansoprazole 30 mg bd, metronidazole 500 mg tds, bismuth subcitrate 240 mg bd, and tetracycline chloride 500 mg qds (LMBT). Cure was definded as a negative 13 C urea breath test 2 mo after treatment. RESULTS: Seven patients were withdrawn after randomisation. Fifty patients were assigned to LAC The intention-to-treat cure rates were 92% and 91%, respectively, while the per-protocol cure rates were 92% and 97%, respectively. Side effects were common, with 56% expe Symptoms of vomiting, diarrhea and black stools were significantly more common in the LMBT group. Patient compliance was 100% for triple therapy and 86% for quadruple therapy (P < 0.01). One-third of patients in both groups were still taking acid-reducing medications at six-month follow-up. CONCLUSION: One-week triple and quadruple therapies have similar intention-to-treat eradication rates. Certain side effects are more common with quadruple therapy, which can compromise patient compliance. Patient education or modifi cations to the regimen are alternative options to improve compliance of the quadruple regimen.