Data from the FDA's Adverse Event Reporting System was reviewed, which suggested the link between PPIs and C diff. Those persons with the highest risk are the elderly, have other medical conditions, or who are taking broad spectrum antibiotics. These factors can increase the risk of C. diff by themselves, but the FDA said PPIs couldn't be excluded as a risk factor.
The drug makers of the PPIs are working on modifying labels to include the possible risk of C. difficile-associated diarrhea.
The FDA is reviewing H2 blockers to determine if there is a higher risk of CDAD associated with them.