Quadruple therapy

Abstract

Bismuth quadruple therapy (BQT) has been used as the second-line rescue therapy in cases where standard triple therapy fails as the first-line treatment. Helicobacter pylori (H. pylori) eradication rates under 7-day regimen are in the range of 63-81 %, and no clearly decreasing trend has yet been observed. Studies on the feasibility of extending the treatment duration of BQT to a 14-day regimen have presented different results. The main problem in extending the treatment duration is increase in side effects. The most recent guidelines recommend BQT as first-line treatment in regions with clarithromycin resistance of 20 % or higher. However, its outcomes are not very promising, with eradication rate lower than 80 %. Increase in metronidazole resistance is considered a contributing factor for the potential failure of BQT. The risk for decrease in eradication rate is especially high in regions where metronidazole resistance exceeds 30 %. Due to the unsatisfactory outcomes of BQT as first- or second-line treatment, which is ascribable to increase in antimicrobial resistance, there is an urgent need for developing a new eradication treatment method.