Minimising the misuse of oxycodone and other pharmaceutical opioids in Australia

Sustained-release opioid drugs have been used increasingly over the past two decades to treat all types of chronic pain, including chronic non-cancer pain.1 Rates of prescribing have increased in developed countries such as Australia, Canada, the United Kingdom and the United States since the beginning of the 21st century.2-4 In the US, aggressive marketing of sustained-release formulations of oxycodone to primary care physicians and directly to patients between 1996 and 20075,6 resulted in a 10-fold increase in their per-capita use, and an alarming increase in the number of deaths from overdose with prescription opioids. In 2007, the number of deaths from oxycodone and other pharmaceutical opioids (11 499) outnumbered overdose deaths from illicit heroin and cocaine combined (around 8000).7

The article by Roxburgh and colleagues in this issue of the Journal8 provides an assessment of harms arising from recent increases in opioid prescribing in Australia.1 Roxburgh and colleagues show that pharmaceutical opioid prescribing has increased, with those for sustained-release forms of oxycodone supplanting those for morphine.8 Most oxycodone prescriptions have been to adults over the age of 50, with the steepest increases in rates of prescribing to patients aged over 70 years.8 These patterns suggest that most prescribing has been for chronic non-malignant pain, the prevalence of which increases steeply with age.1

Increased opioid prescribing has been accompanied by increases in the number of people seeking treatment for dependence on prescribed opioids in Australia. The number of fatal overdoses involving oxycodone has also increased, but, unlike in the US, the number of deaths in Australia from oxycodone reported by Roxburgh and colleagues was much lower (59) than the number of deaths from all other opioids (including heroin; 315) in 2005 (this was the most recent year in which the two could be directly compared).

Roxburgh and colleagues report that in 90% of cases, deaths from oxycodone overdose involved either the use of the drug in combination with other opioids, benzodiazepines and alcohol, or the contribution of concomitant medical conditions. Just over half of the deaths (53%) occurred in people who were prescribed oxycodone, probably for the relief of chronic pain. A quarter of all these deaths, and those of a third of people with no history of illicit injecting drug use, were found to be suicides. Fatal overdoses among those with a history of injecting drug use were more likely to involve males, as is true of overdose deaths in this population more generally.9 Injecting drug users were more likely to be using diverted opioids at the time of their death, although a third were prescribed these drugs.

There are a number of strategies available to governments to reduce pharmaceutical opioid misuse and the harms arising from it.1

Clinical recommendations are as follows:

• First, doctors and patients need to be educated about the risks of dependence on, and overdose of, these drugs, especially when higher doses are prescribed. Patients need to be informed by prescribers and pharmacists about the risk of fatal overdose if they use these drugs in combination with other drugs that depress the central nervous system, whether prescribed ones like benzodiazepines, or the more readily available alcohol.

• Second, clinical guidelines are needed on the place of opioids in the treatment of chronic pain, especially non-cancer pain. There is a need for clearer clinical guidelines for primary health practitioners to ensure that opioids are not used as first-line drugs for chronic pain, but are reserved for use when other forms of treatment have been tried.1,5,10

• Third, clinical priority should be given to reducing suicides in patients who experience chronic pain and who are prescribed opioids. Prescribers need to be cautious in prescribing opioids to depressed patients. They should also enquire about suicidal ideation in patients who have chronic pain and who have been prescribed these drugs long term but have incomplete pain relief.

• Fourth, smaller quantities of these drugs should be prescribed to allow for more regular review of their effectiveness in relieving pain. Compliance with the prescribed medication regimen should be carefully recorded and a clear plan of action should be documented when significant non-compliance is identified. Referral to pain specialists should be considered if pain control is incomplete, and referral to addiction specialists should be considered if dependence on opioids is suspected.

Policy recommendations are as follows:

• Enhanced prescription monitoring systems are needed to reduce both doctor-shopping by patients and imprudent prescribing by doctors. These systems should be computerised, nationally consistent and, ideally, real-time.1,5 It is also critical for doctors and pharmacists to monitor patterns of chronic opioid use in patients whom they see.

• The pharmaceutical industry needs to ensure that these drugs are marketed to prescribers in responsible ways, and that clinical information for patients advises about the risks of using these drugs in combination with other central nervous system depressants.

• Governments need to examine ways of increasing access to buprenorphine and methadone treatment for people who use opioids illicitly, and who may be using pharmaceutical opioids to self-treat.1

If Australian policymakers and doctors want to avoid the disastrous US experience with pharmaceutical opioids, these steps should be taken now while the misuse of these drugs is still a manageable problem. Whatever policies are implemented, it is essential that we assess rigorously their impacts on both the quality use of these medicines in relieving chronic pain and on the harms arising from their inappropriate use.