Background: Medicines reuse involves dispensing quality-checked, unused medication returned by one patient for another, instead of disposal as waste. This is prohibited in UK community pharmacy because storage conditions in a patient’s home could potentially impact on the quality, safety and efficacy of returned medicines. Our 2017 survey examining patients’ intentions to reuse medicines found many favoured medicines reuse. Our aim was to analyse the qualitative comments to explore people’s interpretations of what makes medicines (non-)reusable. Methods: Thematic analysis was used to scrutinize 210 valid qualitative responses to the survey to delineate the themes and super-ordinate categories. Results: Two categories were “medicines as common commodities” versus “medicines as powerful potions”. People’s ideas about medicines aligned closely with other common commodities, exchanged from manufacturers to consumers, with many seeing medicines as commercial goods with economic value sanctioning their reuse. Fewer of the comments aligned with the biomedical notion of medicines as powerful potions, regulated and with legal and ethical boundaries limiting their (re)use. Conclusion: People’s pro-medicines-reuse beliefs align with perceptions of medicines as common commodities. This helps explain why patients returning their medicines to community pharmacies want these to be recycled. It could also explain why governments permit medicines reuse in emergencies.