SUMMARYBackground: Postprandial intragastric acidity is not uniform. Postprandial proximal gastric acid pockets have been described in the present study. Aim: To determine the effects of rabeprazole on regional intragastric acidity and proximal acid pockets. Methods: Ten normal subjects underwent two 8-day oral dosing regimens with placebo or rabeprazole 20 mg each morning in a randomized, double-blind protocol. Oesophago-gastric pH monitoring was performed on days 1 and 8. Results: Rabeprazole increased fasting and postprandial gastric pH to above 4 in each area of the stomach on days 1 and 8. With placebo, acid pockets were identified