Helicobacter pylori eradication decreases the antisecretory activity of omeprazole and lansoprazole. However, rabeprazole is a potent proton pump inhibitor that may not be as affected by H. pylori status.
In this study, researchers from England compared the effect of H. pylori eradication on intragastric acidity and plasma gastrin during dosing with proton pump inhibitors.
The team studied 24 healthy H. pylori-infected volunteers on day 7 of dosing with either placebo, lansoprazole 30 mg, omeprazole 20 mg and rabeprazole 20 mg.
Volunteers were assessed both before, and at least 5 weeks after, H. pylori eradication.
|H. pylori eradication increases intragastric acidity, particularly nocturnal acidity, and decreases plasma gastrin.|
|Alimentary Pharmacology and Therapeutics|
On each occasion, the team measured 24-hour intragastric acidity by gastric aspiration.
They measure plasma gastrin concentrations hourly, from 08.00 to 13.00 hours.
Overall, 16 subjects completed the study.
The research team found that for all groups, H. pylori eradication increased intragastric acidity, particularly nocturnal acidity, and decreased plasma gastrin.
They also found no differences between the 3 drugs with respect to 24-hour acidity, percentage of time pH > 4, or 5-hour plasma gastrin. This was true either before or after H. pylori eradication.
However, before eradication, the percentage nocturnal time at pH > 3 was greater during rabeprazole than during lansoprazole dosing.
Dr Williams’s team concluded, “The increase in intragastric acidity seen after H. pylori eradication during dosing with proton pump inhibitors is a drug-class effect, particularly affecting nocturnal acid control”.
“This is related to increased spontaneous intragastric acidity after H. pylori eradication.”