Impact of Antibiotic Shortages on Antibiotic Utilisation in the Community.

Background: Drug shortages are an increasing and worldwide problem. Oral antibiotics are one of the most used medicines worldwide and have recently been affected by drug shortages. Despite this, little is known about the impact of antibiotic shortages on prescribing practices.

Aim: To explore the impact of oral antibiotic shortages on national antibiotic utilisation.

Methods: A cross-sectional study of oral antibiotic shortages and antibiotic utilisation was conducted using Australian reimbursement and regulatory data from January 2022 to December 2023. All nationally reimbursed oral antibiotics were included in the study. The number and duration of reported antibiotic shortages per product were determined for each active ingredient. The clinical impact was assessed using national utilisation in Defined Daily Doses per 100 000 inhabitants. Changes in trends were analysed using Joinpoint regression.

Results: Shortages were reported for eighteen of the twenty-one (86%) oral antibiotics reimbursed in Australia. For ten active ingredients, shortages did not coincide with changes in utilisation data. No clear relation between the number and duration of shortages and impact on utilisation was observed. Changes in utilisation coinciding with shortages were observed for eight active ingredients. For cefaclor (-20% decrease in utilisation) and roxithromycin (-26% decrease), the impact of shortages is most clearly reflected by decreases in utilisation. For the other six, minor changes in utilisation were observed coinciding with shortages.

Conclusions: Antibiotic shortages were common in Australia during 2022 and 2023. The impact of shortages differs per antibiotic, for some antibiotics there are shortages coinciding with declines in utilisation. For others, shortages occur without apparent changes in utilisation.