Pregabalin misuse skyrockets

Pregabalin-related ambulance attendances have increased 10-fold since 2012, a Victorian study has shown.

Published in the Medical Journal of Australia, the retrospective study on the ambulance attendance in Victoria between 2012–17 found that the increase in acute harm associated with pregabalin misuse strongly correlated with the prescription rate in Australia.¹

‘Patients frequently misused pregabalin with other sedatives, particularly benzodiazepines, and almost 40% of misuse-related events requiring paramedic attendance were suicide attempts,’ the paper stated.

Angus Thompson, Lecturer in Therapeutics and Pharmacy Practice at the University of Tasmania and Accredited Home Medicines Review (HMR) pharmacist, said there has been an ‘explosion’ in the use of pregabalin since it was listed on the Pharmaceutical Benefits Scheme (PBS) for neuropathic pain in 2013.

‘Pregabalin can be a useful medication for some people, but it has been prescribed rather liberally and in some cases to patients who probably weren’t good candidates for it,’ he said.

To curtail the problem, Mr Thompson said pharmacists should counsel patients starting on pregabalin to regard it as a trial in their pain management, much as they would with other pain medicines.

‘The response is so variable, so it is vital to try and set realistic expectations. If patients do get an improvement in their pain and function, and it is tolerated – we’ll (recommend they) carry on,’ he said.

‘If it doesn’t work, we’ll recommend stopping  it. And if it’s got side-effects that are disproportionate to any benefit, then we need to stop it. But whenever we are stopping pregabalin from anything beyond the lowest dose, we need to taper it slowly.’

For some patients taking pregabalin, Mr Thompson suggested that a Chronic Pain MedsCheck or a comprehensive clinical HMR may help facilitate conversations about their pain management  and pregabalin use, along with any other analgesic use.

‘Given that chronic pain and depression are such common comorbidities, the concerns about mood changes and suicidal ideation are particularly pertinent,’ he said.

‘While obviously not wanting to deter a person from trying the drug where it is appropriate for their pain, I would like to see them (and their partner/carer if present) be aware of the need to remain alert to mood changes. If these occur, not to delay in discussing this with their doctor.’

Mr Thompson said that pharmacists have a vital role to play in educating patients regarding the risks and helping to protect them from harm.

‘I actually feel that some patients are quite poorly informed, or they come across as being poorly informed,’ he said.

‘I think some of that comes from the fact that we’re often dealing with people who have had many years of living with sub-optimally managed, persistent pain. Some of them are desperate to try something new, so they’ve perhaps not really absorbed information about the risks.’

It’s also important for pharmacists to have conversations with prescribers, Mr Thompson said.

‘If we have concerns around people losing scripts and capsules, or requesting pregabalin early, we need to flag this with prescribers – whether they are GP’s or pain specialists – and document that we’ve done that,’ he said.

‘If there are cases where it’s happening systematically with the same client, and you’ve tried to intervene by educating the patient and the prescriber but nobody is listening, pharmacists have a responsibility to draw the line.

‘There may be a situation where we need to explain to the patient that we feel declining a supply is appropriate, again documenting the reasons for this and ensuring the prescriber is aware.’

The fact that tricyclics and pregabalin are the only mainstream drugs for neuropathic pain that are PBS funded is also a problem, Mr Thompson suggested.

‘Pain is such a complex issue that clinicians need a range of affordable options, both pharmacological and non-pharmacological, that they can tailor to meet patients needs’ he said.

‘As tricyclics are inappropriate for many patients, we’re trying to minimise the use of opioids and access to multidisciplinary pain clinics is often sub-optimal – it was almost inevitable that pregabalin use was going to skyrocket.’

For further information on pain management, pharmacists can refer to PSA’s 2018 Essential CPE on Overview of pain and pain management (part 1 acute pain and part 2 chronic pain).