Proton pump inhibitor

In medicine, proton pump inhibitors (PPI) are medications that "inhibit H(+)-K(+)-exchanging atpase. They are used as anti-ulcer agents and sometimes in place of histamine H2 antagonists for gastroesophageal reflux."

Adverse effects
Proton pump inhibitors may be associated with spontaneous bacterial peritonitis. These drugs may also be associated with pneumonia, Clostridium difficile diarrhea, and fractures.