New Canadian guideline released on opioid use for chronic non-cancer pain

A new evidence-based Canadian Guideline for Safe and Effective Use of Opioids for Chronic Non-cancer pain was released in May.

Published: July 20, 2010

"Joe (a pseudonym) worked at a pizza parlour for many years before he was injured. His employer assured the workers’ compensation board that light work was available, but in practice Joe was simply told to go back to his regular job. Joe complied, not wanting to lose his job. He took increasing amounts of painkillers to manage his pain. By the time he was re-injured a third time, he was consuming eight Percocets daily and was addicted.

A true story, excerpted from Red Flags, Green Lights: A Guide to Identifying and Solving Return- to-Work Problems.

It’s impossible to know how many injured “Joes” are out there, struggling to manage their pain at work and risking medication misuse.

And for all the Joes, there are people who may not be receiving narcotic painkillers such as Percocet to relieve their pain, because their doctors may be concerned about addiction and other safety issues. In one survey, one in three Canadian family physicians said they would never prescribe narcotics – also known as opioids – even for severe pain (In press, Canadian Family Physician).

Addressing these two issues – opioid misuse on the one hand, and undertreated pain on the other – was one intent behind the new evidence-based Canadian Guideline for Safe and Effective Use of Opioids for Chronic Non-cancer pain, which was released in May.

Opioids are effective, and people with pain have the right to be treated with them, says Dr. Andrea Furlan, an IWH associate scientist who led a systematic research review, which underpins the guideline’s 24 recommendations. But opioid use does present risks and potential harms, so prescribers and dispensers have to prevent these as much as they can.

An overview of the guideline was published in the Canadian Medical Association Journal (vol. 182, no. 13, pp. 923-930), and the full 200-page guideline is available at

Opioids are a class of chemicals that include morphine, codeine and oxycodone, among others. The hesitation to prescribe can arise because of concerns about their potential harms. Some patients may take their pills more often than prescribed to manage pain, or to experience the side effects of euphoria and energy, which can lead to addiction. Any opioid can be diverted to the illicit market, although in recent years, oxycodone (sold as OxyContin) frequently makes headlines in this regard. Opioids can also interact with other drugs such as benzodiazepines, resulting in serious complications including overdose and death.

Opioid use has been growing. Forty per cent more workers have been prescribed opioids compared to 10 years ago, the Ontario Workplace Safety and Insurance Board (WSIB) reports on its website. Over that same time period, the number of prescriptions to workers receiving claims has gone up by 100 per cent. Since 2006, the doses prescribed by physicians have also increased.

Several Canadian provincial workers’ compensation boards, including Ontario, Newfoundland, Alberta and British Columbia, have established policies or guidelines for physicians concerning the initiation or continuation of opioid prescriptions.

Opioid prescribing is also increasing in the wider community. Between 1991 and 2007, oxycodone prescriptions jumped from 23 to 197 prescriptions per 1,000 individuals, according to a 2009 report in the Canadian Medical Association Journal (vol. 181, no. 12, pp. 891-896). There have also been increases in doses of long-acting oxycodone. Longer-acting versions require one or two pills a day, while patients using shorter-acting versions, such as Tylenol with codeine, may have to take five or six pills daily.

There has been growing concern from both the public and health-care professionals about safe opioid use, says Rhoda Reardon, acting manager of research and evaluation at the College of Physicians and Surgeons of Ontario (CPSO). Among those taking opioids, there has also been a rise in serious injuries and overdose deaths.

For clinical guidance on opioid prescription, the CPSO decided to update the opioid section of its chronic pain guidelines in 2007, says Reardon. All of the country’s physician regulatory colleges agreed to participate in this update. Collectively, they formed the National Opioid Use Guideline Group (NOUGG), which is co-chaired by Reardon and Clarence Weppler, manager of physician prescribing practices at the College of Physicians & Surgeons of Alberta.

This group coordinated the development of the guideline and its implementation, involving almost 100 participants from across the country.

Furlan led the research team that looked at the effectiveness of opioids in treating chronic non-cancer pain, based on her previous meta-analysis from 2006. IWH provided systematic review methodological expertise for this review, and the research team also included physicians specializing in addictions and pain management.

To ensure the guideline was both relevant and useful, a national advisory panel with direct practice experience was formed. It consisted of 49 individuals representing family physicians, pain or addiction physicians, nurses, pharmacists, psychologists and patients. They reviewed recommendations in four rounds, provided feedback to the researchers, and came to consensus on the final recommendations.

Now that the guideline is complete, a national faculty is involved in disseminating it and fostering collaboration among different groups. This faculty includes provincial partners and representatives from national bodies such as the Canadian Medical Association, Canadian Hospital Pharmacist Association, Canadian Pain Society and the Canadian Council on Substance Abuse, among others.

An overview of the guideline

The overall goal of the guideline is to reduce pain and improve functioning in patients, with fewer side effects, complications or deaths. Another purpose is to help physicians who are uncomfortable with prescribing opioids, says Furlan. Physicians can take steps to assess the risks. If they follow the guidelines, they can be confident that they are not causing harm to their patients.

Opioids should only be prescribed after other treatment options have been tried and failed. The guideline also notes that medication alone is often not enough to manage pain, and other effective approaches should be considered as well. The guideline is organized into five “clusters.” While the guideline is intended for all patients with chronic non-cancer pain, the practical guidance in each cluster also naturally applies to injured workers.

Cluster 1 concerns the decision to initiate opioids. The recommendations in this cluster provide information on assessing the patient and addiction risk screening. “Can the pain be treated? Do you know the person well? Do they have a history of addiction or psychiatric problems?” are among the questions addressed at this stage, Furlan says. This cluster also describes risks, side effects and the tapering of sedatives (benzodiazepines) to avoid drug interactions. In addition, it introduces the practice of urine screening. This practice may help the physician to manage risks of drug interactions, and to make sure that the correct doses are being taken. Some research suggests that having a signed treatment agreement with a patient, as well as the use of urine screens, may reduce opioid misuse, Furlan says.

Cluster 2 provides guidance for how to proceed with the prescription. The guideline’s approach is to start with a trial of “stepped” selection and dosing, to determine the optimal dose. The “optimal dose” is based on a balance of three factors: effective pain relief and improved functioning, minimal benefits from a dose increase, and manageable side effects or complications. Within this cluster the concept of a “watchful dose” is also introduced. It asserts that most chronic non-cancer patients can be managed effectively with a dose at or below 200 mg of morphine or equivalent per day. (Because there are so many forms and doses of opioids, they are converted to an equivalent dose to morphine).

Longer-term opioid use is addressed in cluster 3. At this point, discontinuing opioids or switching to other forms of pain relief may be considered. The final two clusters deal with patients who might require particular attention. Cluster 4 concerns opioid prescription in the elderly, in adolescents, in pregnant women or with patients with psychiatric issues. Finally, cluster 5 has guidance on situations where a patient has addiction, shows unacceptable behaviour or there are issues of fraud. It also includes information on prescribing in acute-care settings such as emergency departments or walk-in clinics.

Furlan points out that the guideline can be used for first-time prescriptions, or to reassess when a patient has been taking an opioid for a while. Go back to square one [with these patients] and reassess the necessity. Is it helping patients achieve functioning? There’s a perception that you can’t stop taking opioids, but you can.

Research underpinnings

The starting point for the guideline was the meta-analysis. Following the usual steps of a systematic review, the updated analysis yielded 62 randomized controlled trials (RCTs) of opioid use. RCTs compare a set of patients randomly assigned to receive the treatment with a group receiving a placebo. They are considered the most rigorous type of study. The reviewers found that 90 per cent of the studies they included were high quality.

Overall, opioids were shown to have a moderate effect on reducing pain and a small effect on improving functioning. In cases where information from RCTs wasn’t available to inform guideline recommendations, they were based on observational studies. The team included 122 observational studies to support guideline recommendations. Failing that, expert consensus was reached through the national advisory panel, says Furlan.

One drawback in the research literature is that most of the trials ended at six weeks, so there was little evidence on opioids’ long-term effectiveness. Based on the observational studies, Furlan noted that there may be long-term complications related to sleep apnea (which in turn is an important risk factor for heart attack or stroke), fertility issues in women and impotence in men.

Ongoing activities

To help further inform this issue, IWH Research Associate Nancy Carnide is currently leading a systematic review of studies conducted on opioid use among workers. Specifically, the team is looking at early opioid use among workers and future work disability. The results are expected to be available later this year.

In the United States, an opioid guideline for chronic non-cancer pain was published in early 2009, in the Journal of Pain (vol. 181, pp. 891-896). Furlan noted that there are very few differences between the U.S and Canadian versions. One key difference is that there are many activities aimed at bringing the Canadian guideline to practice. To that end, a variety of events, guides and tools have been planned.

For physicians, there is an Opioid Manager, a clinical support tool to record patient information, reminders about the risk assessment, starting doses, and what kinds of behaviours to look for that indicate addiction. In Ontario, a variety of community workshops are being planned with physicians, pharmacists and local medical officers of health.

The aim of some of these efforts is to foster collaboration among relevant professionals. In the return-to-work (RTW) process, collaboration has been identified as a helpful practice in preventing RTW complications.

Perhaps, in the case of the worker Joe, a physician following the guideline may have been able to realize that Joe was not following his treatment agreement, or may have seen some unusual drug-related behaviours. The physician could have consulted with a pain physician or the pharmacists and compensation board decision-maker, which may have helped prevent Joe’s slide into addiction.