Adherence to antimicrobial agent recommendations and utilization during drug shortages.

Purpose: Antimicrobial shortages occur frequently, but the impact on antimicrobial use is not well defined. The study objectives were to characterize utilization of antimicrobial agents with established restrictions during a medication shortage, assess utilization of shortage antimicrobials following shortage resolution, and examine use of recommended alternative antimicrobials during the shortage period.

Methods: Five antimicrobials were restricted due to shortages from 2015 through 2020. Chart review of inpatients receiving a shortage medication during each restriction period was performed to determine factors influencing adherence to established restriction criteria. To assess antimicrobial utilization during shortages and following shortage resolution, days of therapy per 1,000 patient days were analyzed for each shortage and alternative antimicrobial.

Results: Across 266 patients receiving shortage antimicrobials, antimicrobial use was adherent to restriction criteria for 151 patients (57%). Meropenem, ampicillin/sulbactam, and piperacillin/tazobactam had the greatest adherence. Median duration of therapy was shorter in the nonadherent group than in the adherent group (4 vs 2 days, P < 0.0001). Shortage antimicrobial use was more likely to be nonadherent for indications such as sepsis rule out, surgical prophylaxis, and urinary tract infection. Adherence increased with use of visual cues in the chart (99% vs 94%, P = 0.03). Utilization of shortage agents decreased during shortage and restriction periods. After shortage resolution, utilization exceeded baseline usage for all agents except meropenem and metronidazole, for which usage returned to baseline. Utilization of 1 to 2 recommended alternative agents for each shortage agent significantly increased during the shortage and restriction periods.

Conclusion: Current strategies for restriction significantly decreased utilization of shortage antimicrobials, but additional opportunities exist. Identifying alternative agents and providing visual cues increased adherence.