Spiramycin is comparable to oxytetracycline in eradicating H. pylori when given with ranitidine bismuth citrate and metronidazole

BACKGROUND: We have consistently achieved about 90% eradication of H. pylori with liquid bismuth, metronidazole and oxytetracycline. AIM: To test eradication and adverse events of ranitidine bismuth citrate (RBC) when given with metronidazole and either oxytetracycline or spiramycin. METHODS: One hundred and eighty-three patients were randomized to one of four 10-day regimens: RBC400OM: RBC 400 mg b.d., oxytetracycline 500 mg q.d.s.; RBC400SM: RBC 400 mg b.d., spiramycin 1 g q.d.s.; RBC200OM: RBC 200 mg q.d.s., oxytetracycline 500 mg q.d.s.; RBC200SM: RBC 200 mg q.d.s., spiramycin 1 g q.d.s. Additionally, all patients received metronidazole 400 mg q.d.s. A 14C-urea breath test was performed at 8 weeks. RESULTS: Intention-to-treat eradication rates were 94%, 91%, 94% and 89% with RBC400OM, RBC400SM, RBC200OM and RBC200SM, respectively (P = 0.81). Eradication was significantly higher in ulcer patients (97%) than in those with diagnoses other than ulcer (86%) (P = 0.009). There was a strong tendency to better eradication among those who had never smoked (100%) compared with ex-smokers (93%) and smokers (89%) (P = 0.06). Fifty-three per cent experienced at least one moderate or severe adverse event, and women had more adverse events than men (P = 0.0002). CONCLUSIONS: All four regimens had comparable efficacy and adverse events. Eradication was significantly better in ulcer patients but there was a trend to better eradication in those who smoked less, used less alcohol and exercised more. Adverse events were frequent, perhaps because of the large dose of metronidazole used, but few patients stopped treatment.