Exploring awareness of planetary health and antibiotic disposal advice across Australian Pharmacies: A mystery shopping expedition

•Our results showed 59.4 % of pharmacists advising consumers to dispose of the leftover antibiotic liquid in the bin or by tipping it down the sink or toilet.•More readily accessible information on pharmaceutical waste advice is needed to support pharmacists in practice.•More convenient pharmaceutical waste disposal methods are needed, especially to support those living in rural areas. Inappropriate disposal of unused antimicrobials can push the environment out of balance, and increase the likelihood of antimicrobial-resistant organisms to grow. We aimed to investigate the recommendations for the disposal of unwanted antibiotics given as advice to consumers by community pharmacists practising in Australia. A cross-sectional study using mystery shopping explored pharmacists' recommendations for disposing of unwanted antibiotics. Simulated patients called community pharmacies across Australia for advice on disposing of leftover antibiotic mixtures. Of 1577 pharmacists called across Australia, over 59 % recommended incorrect disposal methods, i.e., putting the leftover antibiotic syrup in the home rubbish bin or down the sink or toilet, 28.4 % recommended putting the unused antibiotic straight into the rubbish bin, and 10 pharmacists recommended throwing the leftover syrup on the grass, soil, or in a street drain. There were 19 pharmacists who did not want to recommend disposal at all; some recommended calling the prescriber to ask. Of the pharmacists who advised consumers to return unwanted antibiotic liquid to their pharmacy, 21 (1.3 % overall) indicated that they would pour it down the sink at the pharmacy upon being returned. Pharmacists' advice on antibiotic disposal varied despite the availability of a national scheme enabling consumers to return unwanted medicines to pharmacies for this purpose. Enhanced education and policies could help pharmacists guide the public on proper disposal.