Considerations for Using Opioids and Cannabis to Treat Chronic Pain

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You’re listening to Living Rheum on ReachMD. On this episode, we’ll discuss the use of cannabis and opioids to treat chronic pain with Dr. Jason Busse. Not only is Dr. Busse a Professor of Anesthesia at McMaster University in Ontario, Canada, but he also presented a session on this exact topic at the 2024 Congress of Clinical Rheumatology. Let’s hear from him now.

Dr. Busse:

So historically, there’s been a lot of use of opioids to manage chronic pain, even chronic noncancer pain, but there has been increasing recognition that the harms were greater than they had originally been perceived to be.  And you probably have heard the term “opioid epidemic,” which has been affecting North America since the mid-1990s until present date.  So there has been an interest in looking at alternatives to opioids to see if there can be a way to reduce reliance on that particular medication.  One of the alternatives that’s becoming of interest is the use of cannabis for therapeutic purposes, and there is increasing legalization in a number of US states providing this as an option for patients; but at the same time, we should have some compelling evidence that this could be an effective intervention.  Otherwise, we may simply be trading one agent that can be harmful for another agent that can be harmful.  And so the role of evidence and guideline recommendations around these two types of options become important. 

I think, certainly, the evidence that we have would make it an easy conclusion that neither opioids or cannabis are first-line therapy for chronic noncancer pain.  There are other alternatives that are often effective and certainly have better safety profiles, so these are both treatment options that are near the end of the therapeutic pathway.  If patients have tried other alternatives that are available to them and they haven’t found success, then it’s a matter of determining what type of patient is in front of you.  Is it someone who potentially could gain more benefits from harms, or are you looking at a patient, because of certain risk factors, that they may be at much higher risk of a harm as opposed to a benefit?  And in many cases, the benefits and harms of opioids and cannabis are fairly closely aligned, which means it’s difficult to know what a patient would prefer until the discussion is had with them and until they’re presented with the best evidence we currently have for benefits and harms and allowed to make a decision that’s consistent with their values and preferences. 

I will say both opioids and cannabis, particularly cannabis that contains THC, which is the psychotropic cannabinoid, they will result in physical dependance.  Any patient that uses either of these drugs will develop a physical dependance after a reasonable brief period of time.  Now dependance is different from addiction.  In terms of trying to mitigate risks, we do have studies now where we’ve looked at risk factors.  So we know, for example, an individual with an active alcohol use disorder, if they’re prescribed an opioid, their risk of suffering an overdose, fatal or nonfatal, goes up about five times.  We know if someone has a history of an opioid use disorder, their chances of experiencing a future overdose when prescribed opioids for chronic pain goes up by about six-fold.  We know that individuals that have a history of mental illness or an active mental illness are somewhere between 1.5 and 2.5 times as likely to experience an overdose depending on the particular condition.  So we do have some knowledge now of risk factors, which allows us to provide guidance around which types of patients are best off avoiding opioids entirely or which ones may want to consider it, but only if after being presented with the information about harms and their elevated risk for a harm, they decide that they place a higher value on the potential benefits versus the risk of harm that they’re at. 

For individuals that are on a stable dose of long-term opioids, we know that the effectiveness tends to attenuate over time, so if they were achieving some benefit at the beginning, they may not continue to achieve a lot of benefit as time goes on.  They may end up continuing to take their opioids not because of a specific benefit, but because they’re managing interdose withdrawal symptoms because again, all of these drugs will result in physical dependance, so it does make sense to talk to patients on stable long-term opioid therapy once every 6 to 12 months and ask them if they would be interested in looking at a trial to see if they can reduce their amount of opioids and not lose the benefits that they believe that they’re achieving from that. 

So there has to be caution taken in terms of prescribing these agents—in particular, opioids—and there has to be caution when you’re looking at deprescribing or tapering people down from these agents as well.