Vonorazan fumarate (TAK-438) is a potassium ion (K+) competitive acid blocker (P-CAB), is a reversible proton pump inhibitor, after entering the human body, in the gastric parietal cells secreting Chemicalbook acid in the last step, by inhibiting K+ and H+-K+ -ATPase (proton pump) binding, terminating gastric acid secretion. To achieve the effect of acid inhibition, this product has a strong and lasting inhibition of gastric acid secretion.