Abstract
The interdigestive pH environment of the stomach fluctuates from 1 to 2. A rise in pH to above 3 occurs either from decreased acid secretion, as in achlorhydria, or iatrogenic acid reduction (anti-secretory drugs: H2-blockers, proton pump inhibitors), neutralization of acid from swallowed food, or reflux of alkaline pancreatic and biliary secretions from the duodenum.