Effects of Changing the Type of H 2 -Blocker in the Treatment of H 2 -Blocker-Resistant Ulcers: Comparison of Roxatidine Acetate Hydrochloride and other H 2 -Blockers

Abstract

The efficacy of switching from one type of H₂-receptor antagonist (H₂-blocker) to another, in the treatment of H₂-blocker-resistant ulcers was investigated using H₂-blockers with five-membered rings (five-membered-ring agents) – such as cimetidine, ranitidine and famotidine – and an H₂-blocker with a six-membered ring, roxatidine. By switching from a five-membered-ring agent to roxatidine in the treatment of five-membered-ring resistant ulcers (study I), gastric ulcers were healed in nine of 19 patients (47%) and duodenal ulcers were healed in eight of nine patients (89%). By switching from roxatidine to one of the five-membered-ring agents in the treatment of roxatidine-resistant ulcers (study II), gastric ulcer was healed in six of 15 patients (40%), and duodenal ulcer was healed in 4 of 10 patients (40%). Particularry in the case of duodenal ulcers, the switch to treatment with roxatidine, which has a different chemical structure from the five-membered-ring agents, may be useful in the treatment of five-membered-ring-resistant ulcers.