Snapshot A 27-year-old comatose man is brought to the trauma bay of the emergency department as a victim of a multi-vehicle collision. On physical exam, the patient does not respond to command has multiple rib fractures and frank bruising throughout his abdomen and face. He is intubated and started on sedation while being mechanically ventilated. In the intensive care unit, the resident starts the patient on pantoprazole in anticipation of prolonged mechanical ventilation. However, the pharmacist requests consideration of famotidine instead to decrease risk of C. difficile infection. Introduction Drugs Pantoprazole Lansoprazole Omeprazole Mechanism of action irreversibly inhibit H+/K+-ATPase in gastric parietal cells Clinical use peptic ulcer disease gastritis GERD Zollinger-Ellison syndrome Adverse effects gastrointestinal nausea, diarrhea, abdominal pain, flatulence ↑ risk of C. difficile infection reactive hypergastrinemia ↓ absorption of iron and vitamin B12 hypomagnesemia with long-term use ↓ absorption of calcium and increased risk of osteoporosis in long-term administration others ↑ risk of pneumonia acute interstitial nephritis (rare)