Pantoprazole is a proton pump inhibitor used to reduce stomach acid production. It is used to treat stomach ulcers, GERD, and Zollinger-Ellison syndrome. Pantoprazole works by covalently binding to proton pumps in the stomach's gastric parietal cells for up to 24 hours to inhibit acid secretion. Potential side effects include nausea, diarrhea, weakness, headaches, and skin rashes. Drug interactions can occur with medications like nelfinavir, warfarin, and digoxin, so caution is recommended when taking other drugs. Pantoprazole should also be used carefully in patients with liver disease or osteoporosis, and its safety during pregnancy