Promoting the appropriate supply of medicines

A survey of 452 New Zealanders from around the country, reported in 2009, found over 60 per cent of respondents indicated they had leftover or unwanted prescription medications in their home at the time of the questionnaire, and fewer than one in four people return their pharmaceutical waste to pharmacies.³

A 2016 Australian audit of 704 tonnes of unwanted medicines found the most commonly returned medicines were unexpired opened packets of medicines for the treatment of acute conditions.⁴ Internationally, for medicines returned to pharmacies, studies have shown:

• 65 per cent of items contained greater than 65 per cent of the amount originally supplied.⁵
• 66 per cent of items were medications dispensed for greater than a one-month period.⁶

Overprescribing is just one reason unused medications accumulate in the home, but it magnifies the problem when other events come into play – these include:

• A patient’s death.
• Change of treatment or dose.
• Adverse effects or lack of efficacy leading to treatment cessation.
• Resolution of the condition.
• Dispensing not being individualised to patient need.
• Expiry of medicines.
• Non-adherence due to, for example:
  • poor memory
  • physical barriers (eg, difficult packaging)
  • complex or asymptomatic conditions, such as hypertension, and an accompanying lack of education/understanding of the reasons for taking (and consequences of not taking) the medicine.⁷

Clinical scenarios that are complex or have the potential for change (eg, multimorbidity with polypharmacy, frailty) can make appropriate prescribing difficult, and with that comes the risk of overprescribing. Prescribing can also be challenging in the early treatment of conditions – where the need for modification is likely⁸ – or where “as required” medication is prescribed in standard pack sizes, such as for as pain, nausea or vomiting.^8,9

Cost, stockpiling and waste

In 2016, Medicines New Zealand determined that about 76 per cent of patients do not finish their prescribed course of medicine.⁷ The $40 million cost of medicines wastage represented 5 per cent of the then $800 million annual spend on pharmaceuticals, according to health IT provider SimplHealth.⁷ On top of this comes the cost of dispensing and disposal of unwanted medication, and the time taken for health professionals to sort patient medications (eg, during home intervention or hospital admission).

Oversupply also increases stress on the supply chain and the potential for shortages while reducing the predictability for demand.

Environmentally, pharmaceutical waste can cause immediate harm to those who handle it and cumulative damage by contaminating the environment.¹⁰ Pharmaceutical waste collected by community and hospital pharmacies in Auckland increased more than fourfold from 2016 to 2020¹⁰ (possibly due in part to PPE contaminated with pharmaceuticals).

Regional practices for the return, handling and disposal of unwanted pharmaceuticals vary. Even when medicines are returned to pharmacies, they may still be incorrectly processed. Cytotoxic waste needs to be separated for incineration and the remainder sent for autoclave processing, and then to landfill – the autoclave does not deactivate the pharmaceutical waste, and the potential for leaching into soil and groundwater remains.¹¹ Inappropriate direct disposal (into the wastewater system) should be avoided because sewage and water treatment facilities are not designed for pharmaceutical waste. In one New Zealand study, it was found that less than 50 per cent of some drugs (eg, trimethoprim, metoprolol) are removed by wastewater treatment before being discharged into the environment.^10,12

Safety

Oversupply of medicines and patient stockpiling are safety issues with negative implications for good clinical practice and professional responsibility. These include:

• Personal safety – intentional or inadvertent overdose; harm from inappropriate use of no-longer indicated or expired medication; excess supplies at home can lead to confusion about what needs to be taken.
• Family safety – risk of harm from shared; accidental poisoning to young children; intentional overdose.
• Community safety – crime, morbidity/mortality due to oversupply of medicines with abuse potential (much of the controlled drug supply “on the street” comes from legally dispensed prescriptions).¹³

A 2017 evidence review found that 42 to 71 per cent of opioid tablets prescribed after surgery were unused.¹⁴ While it is important that excess supplies of potentially dangerous medicines such as oxycodone and tramadol are removed from households, the same applies to all unused medicines.

The New Zealand National Poisons Centre has analysed data from contacts in the period 2018 to 2020. Their report finds all age groups were frequently exposed to paracetamol, while youth and adults were also frequently exposed to psychiatric medicines, and older adults to cardiac medicines.¹⁵ Youth and adults had more intentional exposures compared with children (often exploratory) and older adults who frequently had unintentional exposures and exposures due to therapeutic errors. The authors commented that, “medicines no longer acutely required or already expired were often kept ‘just in case,’ which may lead to accumulation in the household and cause added risk if there is unintended access by children or others”.¹⁵

There are a number of methods that help promote appropriate prescribing and dispensing and reduce oversupply and wastage. And at an individual level, medicines wastage is best addressed before it begins.

Patient education and shared decision-making

• Encourage shared decision-making with the patient to choose a treatment consistent with their values and preferences.⁷
• Minimise health literacy issues by speaking with the patient about their condition, the effects of the medication, the reasons for taking it and the consequences of not taking it.⁷ This is particularly useful in complex conditions and the prevention or treatment of long-term conditions such as hypertension, gout, chronic pain and depression.
• Be aware of physical and/or psychological barriers a patient might have to taking their medicine as directed – for example, hand arthritis, poor memory or vision, alcohol dependency, depression.⁷

Thoughtful prescribing

• Be aware that bulk prescribing frequently leads to incomplete use of the supply.⁷ Remember, this can also occur with over-the-counter products provided by prescription.
• Treatment change is one of the most common reasons for unused medications. Changes often occur during early treatment;⁸ therefore, it may be prudent to prescribe a smaller amount of medication or “close control” for the first month of a three-month prescription, if a dosage change is anticipated and the patient is due to be reviewed.⁹ (Absence of a co-payment now makes prescription adjustments less costly for the patient at the point of dispensing.)
• The large number of “as required” medications being returned by patients^9,15,22,23 may indicate oversupply. Specifying an appropriate quantity on prescriptions may reduce wastage and allow better monitoring of the condition (see the example in the Panel on paracetamol). Where “as required” medicines (eg, paracetamol, asthma reliever inhalers) form part of a long-term medications plan, a simple enquiry about what quantities a patient has at home will shed light on what actually needs to be prescribed. This could also be asked by the dispensing pharmacist. Patients may be reluctant to confess they have a stockpile; it is best to ask open questions rather than make assumptions.⁹

Adherence monitoring

• Ask patients regularly if they are using the medicines they have been prescribed.⁹ The Royal College of Physicians, London recommends every patient contact should be taken as an opportunity to check medication compliance, to minimise the need to dispose of unused medication.²⁴
• Limit the number of repeat prescriptions before an appointment for a medicines review is triggered, to check for adherence.⁹
• Consider using patient portals and other technologies to communicate with patients outside the consulting room.⁷

A 2015 BPACnz article provides a helpful reminder of strategies that may reduce medical wastage and safety issues in the home; these include:²⁰

• regularly reviewing a patient’s current medicines
• using trial periods for new medicines
• prescribing appropriate quantities of “as required” medicines
• putting prescriptions on hold at the pharmacy (for up to three months) where it is uncertain if a medicine will be needed
• utilising pharmacy Long Term Condition services.

Of all the reasons to avoid oversupply of medicine, perhaps the message regarding safety will appeal the most.