Pumaprazole is a reversible proton pump antagonist. It inhibits basal acid secretion in the Ghosh-Schild rat with higher efficacy compared to ranitidine. It displays identical ID50 values on day 1 (11 μmol/kg, 95% confidence limits of 5 and 23) and on day 7 (10 μmol/kg, 95% confidence limits of 4 and 23) in a repeated dose study. The lower dose (27 μmol/kg) rapidly elevates luminal pH to almost neutrality, and the higher dose (54 μmol/kg) further prolongs this pH-elevating effect.
