Vol.73 No.5 September 2025

Impact of the implementation of restricted approval for carbapenems following supply limitations on antibiotic usage and Pseudomonas aeruginosa susceptibility rates

Ryou Sakamoto^{1, 2)}, Norito Nishiyama^{1, 2)}, Masayuki Tanaka³⁾, Yuki Yuzuriha¹⁾ and Naoyuki Miyashita¹⁾

¹⁾Division of Infection Control and Prevention, Kansai Medical University Hospital, 3-1 Shinmachi 2 Chome, Hirakata City, Osaka, Japan
²⁾Department of Pharmacy, Kansai Medical University Hospital
³⁾Department of Clinical Pharmacy, Setsunan University

Abstract

Carbapenems have a broad antibacterial spectrum and are widely used as empirical therapy for severe infections. However, excessive use of carbapenems increases the emergence of antimicrobial-resistant bacteria; thus, appropriate use of this antibiotic class is necessary. However, a recent restriction in antibiotic supply has become a global problem, seriously affecting the treatment of antimicrobial-resistant bacteria and antimicrobial stewardship activities. In particular, supply restrictions on carbapenems, starting with the supply of meropenem in September 2022, have severely restricted empirical therapy for severe infections and the treatment of antimicrobial-resistant bacteria.
Since the supply of carbapenems was also restricted at Kansai Medical University Hospital, the hospital changed from a conventional notification system to the implementation of restricted approval for carbapenems, effective October 26, 2022, and promoted the appropriate use of carbapenems by actively conducting carbapenem-sparing, and the amount of carbapenems used also decreased.
Days of therapy (DOT) for carbapenems decreased by approximately 80% following the implementation of restricted approval for carbapenems. In contrast, carbapenem-sparing resulted in an increase in the DOT for other antimicrobials, although there was no change in the antimicrobial drug spectrum. Furthermore, while the susceptibility rate of Pseudomonas aeruginosa to the three antimicrobial agents, penicillins, cephalosporins, and fluoroquinolones, did not deteriorate, the susceptibility rate to carbapenems improved significantly to over 90%. These results suggest that carbapenems may be useful for treating drug-resistant P. aeruginosa and in antibiotic stewardship activities.

Key word

carbapenems, antimicrobial stewardship, days of therapy, days of antibiotic spectrum coverage, Pseudomonas aeruginosa

Received

February 18, 2025

Accepted

June 16, 2025

Jpn. J. Chemother. 73 (5): 378-385, 2025