The present invention is related to oral compositions comprising an irreversible gastric H+/K+-ATPase proton pump inhibitor (PPI) as a gastric acid secretion inhibitor and succinc acid as a parietal cell activator in the gastric lumen. The compositions of the present invention are capable of enhancing the anti-acid activity of PPI in the stomach. The present invention further relates to a method of using such compositions to reduce gastric acid secretion in a mammal.
