Ranitidine multicenter study on slow-response duodenal ulcer patients.

Twenty-six Italian Centers participated in the present study, the aim of which was to compare, in a double blind manner, the effectiveness of ranitidine 150 mg b.i.d. and ranitidine 300 mg b.i.d. in duodenal ulcer patients, who were considered likely to be slow-responders on the basis of clinical and anamnestic criteria. The results of this study show no statistically significant differences in healing rates between the two groups of patients treated with the different doses of ranitidine. After 4 weeks of treatment, healing rates were 73.3% for ranitidine 150 mg b.i.d. (131 patients) and 76.1% for ranitidine 300 mg b.i.d. (134) patients). After 8 weeks of treatment, cumulative healing rates were 91.5% and 93.9%, respectively. There were no differences in the relief of symptoms. The percentage of ulcers healed after four weeks of treatment with ranitidine 150 mg b.i.d. was lower than generally reported (1, 2), probably reflecting the strict selection criteria. However, at least in this population, the higher dose, with its increased inhibition of gastric acid secretion, failed to offer any significant advantage. Other factors, not dealt with in this study, might help identify the slow-responder and the non-responder, as also those who would benefit from an increased dose.