Comparison between two different posologies of ranitidine on 24-hour gastric acidity in duodenal ulcer patients.

Eight outpatients with active duodenal ulcer, endoscopically proven, entered a controlled double-dummy cross-over study aimed at comparing the effects of ranitidine 150 mg b.i.d. and 300 mg nocte on 24-h intragastric titratable acidity and pH. Both treatments markedly inhibited (p less than 0.01) gastric acid secretion when the mean 24-h results were compared. When the effects of two posologies on nocturnal and diurnal periods were considered separately, 300 mg appeared to control nocturnal acid secretion more actively, while during the day 150 mg b.i.d. seemed to be the more active. Since nocturnal hypersecretion can be considered an important determinant of duodenal ulcer, a large bedtime dose of ranitidine seems to represent a valid therapeutic approach to this disease.