High dose narcotic painkillers prescribed: study

Patients are receiving strong pain medications such as morphine and OxyContin at doses higher than recommended, a new study of people on social assistance in Ontario finds.

The study, published Tuesday in the journal Open Medicine, looked at prescriptions for patients aged 15 to 64 that were paid by Ontario's public drug plan. Opioid drugs such as OxyContin help recovery from surgery or back injury. But some people can become addicted to the medication. 

During the 2003 to 2008 study period, doctors in the province often prescribed opioids on a long-term basis. In one in three cases, the doses for non-cancer patients were higher than recommended by Canadian clinical guidelines, said the study's lead author, Tara Gomes, an epidemiologist at the Institute for Clinical Evaluative Sciences in Toronto.

Among patients prescribed high or very high doses of opioids in 2004, 19 per cent of deaths during the next two years were related to the medications, the researchers found.

Participants were divided into three dose categories based on their first 90 days of opioid treatment in each year:

• Moderate — an average daily dose of up to 200 mg of oral morphine or equivalent.
• High — average daily dose between 201 mg and 400 mg.
• Very high  — average dose of more than 400 mg. 

The number of people dying was 10 times higher than in the general population within two years, the researchers found. The deaths occurred at an average age of 46.

"These are very young people who are looking to be treated for pain-related causes and may develop a dependency or an addiction to these drugs and are dying," said Gomes. "That to me is the major problem."

The Office of the Chief Coroner for Ontario classified 302 deaths as opioid-related, including 45 confirmed as suicides, according to the study.

In some cases, doctors don't properly understand the risks of the drugs that they're prescribing. A bigger concern, Gomes said, is patients who shop around looking for multiple prescriptions, a practice known as multi-doctoring.

Ontario is working on a network of electronic records showing a patient's prescribing history to allow physicians and pharmacists to see if a patient has filled other prescriptions for narcotic painkillers.

The network won't be up and running until later this year.