Half of Canadians being prescribed fentanyl are at serious risk because their doctors failed to follow safe prescribing guidelines for the powerful painkiller, a new study has found.
The study, published Monday in the Canadian Medical Association Journal, found that 50 per cent of adults prescribed fentanyl had previously never been on an opioid painkiller, putting them at risk of accidental overdose, respiratory depression and death.
Fentanyl is a strong opioid painkiller that's 100 times more potent than morphine. Prescribing guidelines tell doctors to only prescribe fentanyl to people who have already been taking another opioid, thereby giving their bodies a chance to get used to the drug. Fentanyl is usually prescribed in the form of a transdermal patch that gives a controlled stream of medication over the course of a few days.
Despite numerous safety warnings from Health Canada and other organizations about the dangers of fentanyl and the need for better prescribing and education for patients, rates of unsafe prescribing continue, said Dr. Shawn Bugden, study author and associate professor in the College of Pharmacy at the University of Manitoba.
"We need to be much more careful and judicious about the use of opioids in chronic non-cancer pain," he said.
Canada is the world's second leading per capita consumer of opioid painkillers, behind the United States.
Prescriptions for opioids skyrocketed in Canada in the mid-1990s, following the introduction of OxyContin, a controlled-release pill designed to deliver analgesic effects over the course of many hours. The medication was seen as an important landmark for people with debilitating pain, freeing them from having to take numerous doses of other medications a day.
But the downside is that OxyContin, and the dozens of other opioids now available in Canada, are highly addictive and risky. Patients who take them can become dependent in the course of a few weeks and some of those users will become addicted, which may lead them to turn to illicit fentanyl or other street drugs to continue to get high.
Use of illicit fentanyl, which is often pressed into a pill form that resembles OxyContin, is on the rise in many parts of Canada. And because opioids cause respiratory depression, the number of people who have died from accidental overdoses has risen. (Data released by the B.C. Coroners Service in March, however, suggests that while fentanyl deaths are on the rise, the vast majority of deaths are caused by other drugs, such as cocaine, crystal meth and heroin.)
The new study looked at patients prescribed fentanyl in Manitoba from 2001 to 2013. Over all, three-quarters of prescriptions were considered unsafe, with women and patients older than 65 facing the greatest risks. The rate of unsafe prescribing declined over the course of the study period, going from 87 per cent in 2001 to 50 per cent in 2012.
But the numbers are still far too high, especially considering public attention to the opioid epidemic, said Dr. David Juurlink, one of Canada's leading advocates calling attention to the country's opioid crisis.
"Fentanyl is our most potent opioid for outpatient use and it should be used very rarely, for patients with chronic pain," he said.