Pantoprazole 40mg (under the brand name Pantomax) is a medication used primarily to reduce the production of stomach acid. It belongs to a class of drugs known as proton pump inhibitors (PPIs). Pantoprazole works by inhibiting the proton pump (H+/K+ ATPase) in the stomach lining. This proton pump is responsible for the final step in the production of gastric acid. By blocking this pump, Pantoprazole significantly reduces the amount of acid the stomach produces, which helps to heal ulcers, alleviate symptoms of GERD, and prevent acid-related damage to the esophagus and stomach.