NHS funds; in the bin, down the sink and flushed away
Around 2.7 million prescription items are dispensed daily in the UK, an average of 18.7 items per person per year . The World Health Organisation (WHO) estimates that only 50% of people follow their prescriptions correctly , through non-adherence, lack of compliance or other factors, meaning that medication is often left unused. The result is that the NHS spends an estimated £300 million a year on unused medication , of which half is believed to be avoidable.
Given this national problem, a current research project within the Centre for SMART is investigating solutions for preventing overprescribing and underusing of prescription items within the UK.
As part of the current investigation, a public survey was conducted to better understand ordering habits, reasons for unused medication and current attitudes towards disposal. The survey revealed that the main reasons for unused medication were; the medication going out of date, the patient’s medication changing, patients choosing to stop taking items or patients recovering from ailments. Overall the survey showed that there is a need to assess patients’ requirements more regularly without adding cost and inconvenience to the NHS.
Over prescribing can cause an increase of waste; patients may over order items with a ‘just in case’ attitude, or automatically reorder all items on repeat without checking if they finished the previous batch. One survey stated; “When medication is relied upon, a user has no choice but to stockpile for their own safety,” indicating that the issue may not solely be user oriented, but rather an undesirable feature of the current system. This ‘rainy day’ attitude of the public can lead to stockpiling prescription items, which eventually have to be disposed of, creating a problem in its own right. Incorrect disposal can lead to a wide array of environmental issues. Discarding unused medication down the drain or toilet can contaminate local water, as the active pharmaceutical ingredients (APIs) can pass through the filters at waste water treatment plants (WWTPs) .
Furthermore, discarding through general waste can lead to issues such as accidental consumption by children or wildlife, may lead to people raiding the waste streams to sell on the drugs illegally and landfill leaching can contaminate the water system. 
Returning unused medication to pharmacy is considered best practice within the UK, and often seen as the environmentally conscious approach. However with a lack of high temperature incinerators in the UK, the unused medication often travels long distances to be destroyed . Compounding the matter, incineration of medical waste can produce highly toxic chemicals , with costs of disposal escalating up to £1,900 per tonne. 
This overall problem has not gone unnoticed; the Sustainable Development Unit (SDU) of the NHS, aims to deliver high quality and improved public health without exhausting natural resources or causing severe ecological damage  and their future plans seek to minimise waste resulting from unused medication, by improving repeat dispensing and encouraging cost effective prescribing.
The problem is complex and any potential solutions are, as yet, unclear. What is for certain is that, confusion over the correct method of disposal, along with consistent over dispensing and underusing of pharmaceutical items within the UK is generating harmful waste, whilst depleting scarce NHS funds.