Effect of intravenous infusion of omeprazole and ranitidine on twenty-four-hour intragastric pH in patients with a history of duodenal ulcer.

The effect on intragastric pH of two different dose regimens of continuous intravenous infusion of omeprazole (4 or 8 mg/h after a bolus of 80 mg), and ranitidine (0.25 mg/kg/h after a bolus of 50 mg) was studied in 10 patients with duodenal ulcer disease in symptomatic remission. The pH was monitored over 24-hour periods during fasting in a cross-over, randomised design including a baseline period. With the high omeprazole dose it was possible to maintain a pH > or = 4 in all patients but 1 and 6 of the patients also maintained a pH > or = 6. The lower dose of omeprazole seemed to be somewhat less effective. Continuous infusion of ranitidine was as efficient as the higher omeprazole infusion although with a tendency to decreased pH levels towards the end of the 24-hour period. Thus, in order to obtain consistently high pH levels of 4-6 over a prolonged period a continuous infusion of omeprazole, an 80-mg bolus plus a continuous infusion of 8 mg/h seem to be needed.