Antimicrobial resistance (AMR) is a significant public health issue. Many nations have developed an AMR action plan incorporating various strategies to address this challenge [1]. The Japanese AMR action plan was launched in 2016 [2], and acute care hospitals are now required to implement an antimicrobial stewardship program (ASP) [3], [4]. Clinical pharmacists play a central role in ASPs by collaborating with infectious disease specialists [5]. However, owing to the shortage of infectious disease specialists in Japan, non-infectious disease specialists across various healthcare settings are made to serve as the lead physicians. However, the latter often lack expertise in managing infectious diseases and are unable to dedicate sufficient time to ASP activities, thus forcing pharmacists to take the lead in these programs [6], [7], [8].

While there are numerous studies of the short-term effects of pharmacist-led ASPs on antimicrobial use [9], [10], [11], the data on the long-term effects are scarce, particularly in small to medium-sized hospitals in Japan, which make up a significant proportion of the nation’s healthcare institutions [12], [13]. Furthermore, barriers, such as human resource shortages and the lack of career development, have been identified as obstacles to the participation of clinical pharmacists in ASPs, especially in Asian countries, including Japan [5].

Given these challenges, the present study implemented a stepwise pharmacist-led ASP and retrospectively evaluated its long-term effects in a small, acute-care hospital in Japan. The evaluation focused on antimicrobial use, the rate of antimicrobial resistance, and blood culture practices with the aim of providing insights into the effectiveness of pharmacist-led ASPs in resource-limited settings.