Background: The efficacy of H2-antagonists in combination with antibiotics in curing Helicobacter pylori infection remains controversial, and it is uncertain whether double dose H2-antagonist therapy is superior to standard dose.
Aim: To determine the efficacy of two doses of nizatidine in combination with two antibiotics in the treatment of H. pylori.
Methods: A randomized controlled trial was conducted in 160 patients comparing nizatidine 150 mg with 300 mg b.d. (standard vs. double dose), in combination with clarithromycin (500 mg) and amoxycillin (1000 mg) b.d. for 14 days, in Australia and Taiwan. Compliance was based on a clinical assessment and pill count. H. pylori status was determined by histology (antrum and corpus) and CLO-test.
Results: Baseline clinical and endoscopic findings were similar in both arms of the study. Based on an intention-to-treat analysis, cure of H. pylori was achieved in 78% (95% CI: 70.4-85.4%) in the standard nizatidine dose arm and 70% (95% CI: 61.6-78.2%) in the double dose arm (P=0.2). Similar cure rates were observed in ulcer and non-ulcer patient groups. Compliance was excellent in the single and double dose arms (85 and 91%, respectively).
Conclusions: The combination of nizatidine in standard or double dose with clarithromycin and amoxycillin is similarly efficacious in curing H. pylori infection.