Effect of a proton pump inhibitor AG-1749 (lansoprazole) on intragastric pH

24-hour intragastric pH monitoring

Abstract

Proton pump inhibitors, as agents for use against peptic ulcers, potently suppress gastric acid secretion, as is the case with H₂ receptor antagonists. To evaluate this antisecretory action as objectively as possible, intragastric pH was continuously monitored during 24 hours. Eight subjects were enrolled and divided into 2 treatment groups: a group receiving a daily dose of 30mg of AG-1749 (lansoprazole) and the other group receiving 60mg. Intragastric pH recording was made in each subject before and after the consecutive administration of the drug, and the corresponding pH holding time was calculated to evaluate the effect obtained in each group. The result indicated that the proportion of time in 24 hours after medication during which the pH was maintained above each level was significantly larger than that after placebo administration, and the duration of action was superior to that of H₂-receptor antagosists. From the above, it was concluded that the consecutive administration of ag-1749, at doses of 60mg as well as 30mg, exhibits excellent antisecretory action in terms of intragastric pH control.