The aim of this study was to assess whether Marrie's critical pathway is an effective approach to reduce the duration of antibiotic intravenous therapy and drug cost in patients with community-acquired pneumonia (CAP) in Japan. We conducted a retrospective cohort study in patients with CAP who were admitted to a community hospital or a university hospital. We collected clinical and economic data from medical records and medical fee receipts and estimated drug cost for switching the dosage form using Marrie's critical pathway. Outcomes of this study were change in duration of intravenous therapy and drug cost. Fifty patients with CAP were selected from two hospitals. Actual days of antibiotic intravenous therapy were 9.5±4.2 days; in contrast, estimated days were 1.2±3.0 days (p<0.001). Actual drug cost was 37148±28791 yen; in contrast, estimated drug cost was 8364±18356 yen (p<0.001). Average reduction of days of therapy and drug cost were 8.3 days and 28704 yen, respectively. This study suggests that the implementation of Marrie's critical pathway may be an effective approach to reduce medical resources used for CAP treatment in Japan.
