In-vitro evaluation of nitrofurantoin as an alternative agent for metronidazole in combination antimicrobial therapy against Helicobacter pylori.

Increasing metronidazole resistance suggests the need for alternative antibiotics for combination therapy of Helicobacter pylori infections. We evaluated a metronidazole-resistant and a clarithromycin-resistant strain of H. pylori under stationary growth phase conditions that favoured physiological conditions in order to determine if nitrofurantoin might be a suitable alternative for metronidazole in combination therapy. The results demonstrated that the triple combination of bismuth, tetracycline and nitrofurantoin achieved greater bactericidal activity against these two strains than did the combination of bismuth, tetracycline and metronidazole. These results suggest that further evaluation is warranted.