For patients with community-acquired pneumonia (CAP), doxycycline is associated with a reduced risk for Clostridioides difficile infection (CDI), according to a study published online Nov. 1 in the American Journal of Infection Control.

Ashley L. O’Leary, Pharm.D., from the Veterans Affairs Western New York Healthcare System in Buffalo, and colleagues conducted a retrospective analysis in hospitalized patients in Veterans Affairs Hospitals across the United States to examine whether doxycycline is associated with reduced CDI risk.

During the study timeframe, about 156,107 hospitalized patients received care at a Veterans Affairs Hospital and were diagnosed with CAP. The researchers found that compared with azithromycin, doxycycline used with ceftriaxone for the treatment of pneumonia was associated with a 17 percent reduced risk for CDI. The incidence of CDI was reduced by 45 percent for patients who had a prior history of CDI (odds ratio, 0.55).

“Our analysis found that in patients with a prior history of C. diff, doxycycline was the only factor associated with a reduction in the incidence of new C. diff infections,” senior author Kari A. Mergenhagen, Pharm.D., also from the Veterans Affairs of Western New York Healthcare System, said in a statement.