Comparison of tri-potassium di-citrato bismuthate tablets with ranitidine in healing and relapse of duodenal ulcers.

120 patients were randomly allocated to receive ranitidine 150 mg twice daily or a tri-potassium di-citrato bismuthate (TDB) tablet four times a day in a trial comparing the effects of these drugs in the short-term healing and post-healing relapse rates of duodenal ulceration. At 4 weeks 81% of those on ranitidine and 90% of those on TDB had healed ulcer craters. At 8 weeks 97% of those on ranitidine and 97% of those on TDB had healed. These differences are not significant. After ulcer healing, the cumulative rates of relapse, as determined endoscopically, for symptomatic and symptomless ulcers were 74% for ranitidine and 41% for TDB at 4 months (p less than 0.001), 87% for ranitidine and 55% for TDB at 8 months (p less than 0.001), and 89% for ranitidine and 62% for TDB at 12 months (p less than 0.001). Females had significantly lower relapse rates than males. In the ranitidine group smokers had a higher rate of early relapse and failure to remain healed at 12 months than did non-smokers; no such difference occurred in the TDB-treated group.