PPIs

PPIs inhibit acid secretion by blocking Na+,K+-ATPase, aptly known as the “proton pump,” or the final common pathway of parietal cell acid secretion. PPIs are accepted as superior antisecretory agents to H2RAs for 2 reasons. First, they are able to maintain intragastric pH at or above 4 for longer periods, and second, because of their unique ability to inhibit meal-induced acid secretion. PPIs can be used with excellent acid suppressive effects for indefinite periods and are not associated with tachyphylaxis. Drawbacks to PPI use in children include side effects of headache, diarrhea, constipation, and nausea seen in up to 14% of children. The only PPI that has been approved by the FDA for use in children aged 1 month to 11 months for treatment of erosive esophagitis, is esomeprazole.

PPIs have not been approved for use in North America in infants. In addition, PPI use and resulting gastric achlorhydria in adults and in small cohorts of children retrospective studies have demonstrated an association with an increased incidence of community-acquired infections, alteration in intestinal bacterial flora, and deficiencies of vitamin B₁₂.