Sustainable use of medication: Medication waste and feasibility of redispensing

Many patients do not (entirely) use all pharmacy-dispensed prescription medication. This waste can have considerable consequences both economically, due to the financial loss, and environmentally, when disposed of directly in the environment. Prevention of medication waste is therefore desired. A part of this waste includes medication packages that remain completely unused and opened, which could potentially be redispensed to other patients, thereby minimising medication waste. However, redispensing is not a common pharmacy practice, primarily due to concerns regarding the product quality of medication that has been stored at patients’ homes. In this thesis, medication waste among patients in terms of quantity, cost, preventability, and currently implemented waste-reducing measures was investigated. Additionally, the feasibility of redispensing unused medication was investigated.The outcomes show that medication waste is substantial among all types of patients and has multiple causes that are present in the complete pharmaceutical supply and use chain. Medication waste is mainly of low-cost in the community pharmacy and of high-value in the outpatient pharmacy. Around 40% of the medication waste is preventable and as such indicate the need for waste-preventive measures. Although pharmacists have various opportunities to reduce medication waste, they are less certain about the feasibility for implementation in practice. As such, there is a need for waste-minimising measures that are can be broadly implemented. For maximum success of waste minimisation, all stakeholders involved in the pharmaceutical supply and use chain, including manufactures, distributors, prescribers, pharmacists, patients, and health authorities must be engaged. This includes being aware about the consequences of medication waste and the methods by which it can be reduced. Considering the multitude of causes, a single intervention will not sufficiently minimise waste and thus a multitude of approaches is needed, that should include preventive measures. In addition, the results show that patients and other stakeholders support the redispensing of unused medication given that several requirements, especially a guaranteed product quality, are met. However, considering the pharmacy’s additional processing costs of redispensing this waste-minimising measure would likely be most feasible if applied to expensive medication therapies without specific storage conditions. This can result in substantial cost savings, which were generated after redispensing unused HIV post-exposure prophylaxis (PEP) for medical students who studied abroad. Redispensing of PEP resulted in 74% cost savings in comparison with no redispensing. To conclude, it was found that a redispensing process can be implemented in the pharmacy and can lead to substantial cost savings if a higher proportion of dispensed medication to patients remains completely unused and has been properly stored. Redispensing unused medication requires a thoughtful implementation strategy with comprehensive communication to all stakeholders, paying particular attention to product quality assurance, financial handling, and legal aspects.