Despite limited indications, redundant anaerobic antimicrobial prescriptions (RAAPs) are frequent. The objective of this study was to assess the prevalence and characteristics of RAAPs in German acute care hospitals. In a retrospective data analysis, antimicrobial prescriptions from a point prevalence survey on antimicrobial use in German acute care hospitals in 2016 were analyzed and RAAPs were identified. RAAPs were defined as a patient simultaneously receiving any of the following combinations: Penicillin/beta-lactamase inhibitor (PenBLI) plus clindamycin; PenBLI plus metronidazole; PenBLI plus moxifloxacin; PenBLI plus carbapenem; carbapenem plus clindamycin; carbapenem plus metronidazole; carbapenem plus moxifloxacin; clindamycin plus metronidazole; clindamycin plus moxifloxacin; and metronidazole plus moxifloxacin. Data from 64,412 patients in 218 hospitals were included. Overall, 4486 patients (7%) received two or more antimicrobials. In total, 441 RAAP combinations were identified. PenBLI plus metronidazole was the most common anaerobic combination (N = 166, 38%). The majority of RAAPs were for the treatment of community-acquired (N = 258, 59%) infections. Lower respiratory tract infections (N = 77; 20%) and skin/soft tissue infections (N = 76; 20%) were the most frequently recorded types of infections. RAAPs are common in German hospitals. Reducing redundant antimicrobial coverage should be a key component of future antimicrobial stewardship activities.
