TUESDAY, April 14, 2026 (HealthDay News) -- Few adults with community-acquired pneumonia (CAP) meet eligibility criteria for short-course antibiotic therapy, but outcomes are similar for those with short- and long-course antibiotic therapy, according to a study published online April 14 in the Annals of Internal Medicine.
George Doumat, M.D., from the University of Texas Southwestern in Dallas, and colleagues examined the safety and effectiveness of three- to four- versus five-day or more antibiotic durations in hospitalized adults with CAP who achieved clinical stability by day 3 in an observational emulation of a target trial. Participants received three days of antibiotics and were clinically stable by antibiotic day 3, then received zero to one versus two or more days of additional antibiotics.
After comorbidity, clinical stability, and treatment duration criteria were applied, 5,620 (10.1 percent) of 55,517 hospitalized patients with CAP were eligible for short-course therapy. The researchers found that the median duration of antibiotics was seven days, and only 7.9 percent received three to four days of antibiotics. For short- versus long-course antibiotic therapy, 30-day adjusted risk ratios (95 percent confidence intervals) were 0.89 (0.01 to 2.25), 1.07 (0.81 to 1.42), 0.94 (0.70 to 28), and 1.01 (0.18 to 5.68) for mortality, readmission, urgent visit, and Clostridioides difficile infection, respectively.
"Our study has identified some critical research questions," the authors write. "Given that 90 percent of patients were excluded, we need additional pragmatic, real-world data on the safety and efficacy of shorter antibiotic courses in higher-risk patients, such as those with more severe CAP, immunosuppression, multiple comorbidities, or persistent vital sign abnormalities."