AIM:To evaluate a levofloxacin-doxycycline-based triple therapy with or without a susceptibility culture test in non-responders to Helicobacter pylori(H.pylori) eradication.METHODS:A total of 142(99 women,43 men; mean 53.0 ± 12.7 years) non-responders to more than two H.pylori eradication therapies underwent susceptibility culture tests or were treated with a seven-day triple therapy consisting of esomeprazole,20 mg b.i.d.,levofloxacin,500 mg b.i.d.,and doxycycline,100 mg b.i.d.,randomly associated with(n = 71) or without(n = 71) Lactobacillus casei DG.H.pylori status was checked in all patients at enrollment and at least 8 wk after the end of therapy.Compliance and tolerability of regimens were also assessed.RESULTS:H.pylori eradication was achieved in < 50% of patients [per prototol(PP) = 49%; intention to treat(ITT) = 46%].Eradication rate was higher in patients administered probiotics than in those without(PP = 55% vs 43%; ITT = 54% vs 40%).Estimated primary resistance to levofloxacin was 18% and multiple resistance was 31%.Therapy was well tolerated,and side effects were generally mild,with only one patient experiencing severe effects.CONCLUSION:Third-line levofloxacin-doxycycline triple therapy had a low H.pylori eradication efficacy,though the success and tolerability of this treatment may be enhanced with probiotics. AIM: To evaluate a levofloxacin-doxycycline-based triple therapy with or without a susceptibility culture test in non-responders to Helicobacter pylori (H. pylori) eradication. METHODS: A total of 142 (99 women, 43 men; mean 53.0 ± 12.7 years) non-responders to more than two H. pylori eradication therapies underwent susceptibility culture tests or were treated with a seven-day triple therapy consisting of esomeprazole, 20 mg bid, levofloxacin, 500 mg bid, and doxycycline, 100 mg bid, randomly selected associated with (n = 71) or without (n = 71) Lactobacillus casei DG.H.pylori status was checked in all patients at enrollment and at least 8 weeks after the end of therapy. Compliance and tolerability of regimens were also assessed .RESULTS : H. pylori eradication was achieved in <50% of patients [per prototol (PP) = 49%; intention to treat (ITT) = 46%]. Eradication rate was higher in patients administered probiotics than in those without % vs 43%; ITT = 54% vs 40%). Estimated primary resistance to levoflox acin was 18% and multiple resistance was 31%. Therapy was well tolerated, and side effects were generally mild, with only one patient experiencing severe effects. CONCLUSION: Third-line levofloxacin-doxycycline triple therapy had a low H. pylori eradication efficacy, though the success and tolerability of this treatment may be enhanced with probiotics.