INTRAGASTRIC PH AND SERUM GASTRIN DURING ADMINISTRATION OF DIFFERENT DOSES OF PANTOPRAZOLE IN HEALTHY-SUBJECTS

Objective and design: The effect of increasing doses of pantoprazole, a newly developed proton pump inhibitor, given at once daily doses of 40, 80 and 120 mg, on intragastric pH and serum gastrin profiles was s tudied in 15 healthy subjects in a randomized, double-blind, crossover study and compared to recordings without therapy. Measurements of int ra-gastric pH and serum gastrin were performed on the 7th day of treat ment by continuous pH recording and radioimmunoassay in blood samples obtained in l-h intervals, respectively. Results: Pantoprazole signifi cantly increased gastric pH above basal at all pantoprazole doses stud ied: median 24-h pH rose from 1.2 without therapy to 3.4, 3.3 and 3.6 at 40, 80 and 120 mg daily, respectively. The corresponding integrated 24-h gastrin output was 1632, 2338 and 2248 pg/ml x 24 h compared to 575 pg/ml x 24 h without pantoprazole. There was no interindividual co rrelation between values of 24-h median pH and 24-h gastrin output at any pantoprazole dose studied. However, fasting gastrin levels closely correlated with 24-h gastrin output (r = 0.789; P < 0.0001). The acid inhibitory effect was significantly (P < 0.01) augmented in Helicobac ter pylori positive subjects. Conclusion: It is concluded that pantopr azole is an effective inhibitor of gastric acid secretion. Increasing a single pantoprazole dose above 40 mg does not lead to increased medi an pH elevation. The individual extent of acid inhibition does not pre dict the magnitude of gastrin elevation. Acid inhibition appears more efficient in Helicobacter pylori positive subjects.