Background: Proton pump inhibitor (PPI) therapy is known to suppress gastric acid secretion. Thus PPI therapy may decrease gastric volume and gastric contents available for gastro-oesophageal reflux by decreasing acid secretion.
Aim: To determine the effect of PPI therapy on the gastric volume after a standard meal.
Methods: A total of nine healthy subjects were studied using magnetic resonance imaging, before and after a standard liquid meal mixed with a paramagnetic contrast to help demarcate the gastric region. Images were acquired for a total of 90 min after the meal. Studies were conducted before and following esomeprazole twice daily for 7 days. Images were analysed to determine the gastric liquid volume.
Results: Gastric volume, 15 min after the meal peaked to 611 +/- 37 mL on the control day and 539 +/- 30 mL following the PPI administration (P < 0.001). Average gastric volume remained significantly lower (56 +/- 9 mL, P < 0.05) on the PPI therapy from 5 to 75 min after the meal.
Conclusions: Proton pump inhibitor therapy causes a significant reduction in the gastric contents volume during first 75 min after the meal. In addition to increasing the gastric pH, PPI therapy may decrease the frequency of gastro-oesophageal reflux by decreasing the volume of gastric contents.