The effect of an oral morning dose of nizatidine and ranitidine on gastric acid secretion in duodenal ulcer patients.

The aim of this study was to compare the inhibitory effect and duration of action of a new H2-antagonist, nizatidine (150 mg per os), with ranitidine (150 mg per os) in a group of 10 patients with healed duodenal ulcer. The total inhibitory effect on acid output observed under basal conditions (30 min), during pentagastrin stimulation (120 min) and after stimulation (60 min), is overlapping. However, nizatidine showed a more rapid inhibitory activity -80%, and 31% higher than ranitidine with regard to basal acid output and maximum acid output, during the first hour of stimulation. On the other hand, ranitidine has a more prolonged antisecretory action--more than 27% and 54%, respectively, with regard to maximum acid output during the second hour and the period after hormonal stimulation. Also, variations in pepsin and acid output resulted in overlapping. In conclusion, these results, explainable by the pharmacodynamic property of the two drugs, confirmed the excellent inhibitory capacity of nizatidine, and furnish another reason for its use in clinical practice.