A new ‘Potentially inappropriate medicines’ (PIMs) list unveiled 16 high-risk medicines or medicine classes that could result in negative clinical outcomes, including hospitalisation and death in older patients.

The medicines span a range of different classes, from antiemetics such as chlorpromazine and metoclopramide, to centrally active antihypertensives such as clonidine and methyldopa, and ‘Z drugs’ such as zolpidem and zopiclone, says PIMs list co-author Dr Amy Page FPS, Senior Research Fellow at the University of Western Australia’s School of Allied Health, Pharmacy and President of the PSA Victorian Branch.

‘Some antipsychotics, short, long and medium-acting benzodiazepines, non-steroidal anti-inflammatories (NSAIDs), anticholinergics for incontinence, opioids, tricyclic antidepressants and oral anticoagulants were also included,’ Dr Page said.

The below table details the potentially high-risk medicines (tilt screen in mobile view to see full table).

The updated list was developed to account for new medicines available in Australia since the last iteration was developed 15 years ago, says the researchers. Another key point of difference is the inclusion of specific conditions that make the medicines particularly risky, along with suggested, safer alternatives.

With older Australians often needing to use multiple medicines to manage chronic conditions, between 20–70% are prescribed at least one PIM on the new list.

Here, Dr Page explains how pharmacists from all areas of practice can use the PIM list for risk assessment and to identify alternative therapy approaches for older Australians.

How was the new list compiled?

To come up with the list of medicines that were potentially inappropriate for older Australians the researchers looked at all the existing lists of PIMs available internationally, said Dr Page.

‘We identified that out of 645 unique PIMs, only 416 were available in Australia, with even less (262) subsidised by the Pharmaceutical Benefits Scheme.’

A multidisciplinary expert panel comprising 33 clinicians and researchers specialising in geriatrics, pharmacy, clinical pharmacology, general practice and epidemiology identified 16 medicines and medicine classes that are potentially inappropriate for patients aged 65 and older. 

Why some high-risk medicines are not included

While the new list contains medicines that may be risky to use, that doesn’t mean all high-risk medicines are included in the list.

‘It could be that a high-risk medicine carries a similar risk whether the patient is 20, 40 or 80,’ she said. ‘For example, insulin, while highly beneficial for anyone who has diabetes, has a similar risk profile for different age groups.’

Risk assessment and alternative therapies

To further assess the risks of PIM-listed medicines to older people, each medicine or class is tabled against chronic conditions, or other concurrently used medicines – which could make use particularly dangerous.

Up to 19 medicines or medicine classes had specific conditions that make them more likely to be inappropriate.

‘For example, [it’s recommended] that short-acting benzodiazepines are particularly avoided if patients are particularly frail, prone to falls, or use other medicines with sedative properties,’ said Dr Page.

‘With NSAIDs, the experts [warned] people who had a history of gastrointestinal bleeding or increased bleeding risk, frailty, poor renal function, peptic ulcer disease, multimorbidity, chronic kidney disease, heart failure, or cardiovascular disease were at higher risk.’

Where medicines are potentially inappropriate for older patients, pharmacists can refer to the suggested alternative treatment pathways included in the PIM list.

Of note, among all available short-acting benzodiazepines, alprazolam was considered the most inappropriate.

Alprazolam has increased morbidity and mortality in overdose with possible increased toxicity. It also doesn’t appear to have additional therapeutic benefits when compared with any other benzodiazepines.

While the first-line treatment alternative is non-pharmacological strategies, melatonin could be a safer option, when used for indication of sleep.

‘If a patient actually needed to use a medicine in this class [for example, for short-term management of insomnia or anxiety], temazepam and oxazepam are considered safer alternatives,’ said Dr Page, provided the indication is appropriate.

Use in practice

When conducting Home Medicine Reviews, credentialed pharmacists and those working in general practice, aged care or Aboriginal Community Controlled Health Organisations can also assess whether a PIM might be high risk for a patient with specific chronic conditions, or using other potentially contraindicated medicines.

‘While the PIM may at times be appropriate for an individual, pharmacists should consider if there is a safer alternative, or if the medicine is actually necessary,’ she said.

‘It’s also potentially useful for MedsChecks, or for community or hospital pharmacists when dispensing or reviewing medicines lists.’

For governance-level QUM activities in residential aged care facilities, on-site pharmacists can conduct audits to identify how many residents are using PIMs so there’s a baseline to measure against. 

‘A similar approach would be beneficial in GP practice,’ said Dr Page. ‘GP clinics usually have regular staff and clinical meetings that pharmacists attend, making the process a lot easier when there’s direct access to prescribers.’

New downloadable PIM-list tables

For eases of access, pharmacists can now download tables for use in practice that outline medicines or medicine classes to be avoided in older patients, along with suggested alternatives:

• Potentially inappropriate medicines for older Australians
• Consensus agreement reached on PIMS by condition or scenario.