Australian Study Finds Cannabis Does Little for Pain

By Roger Chriss, PNN Columnist

A controversial study recently published in The Lancet Public Health followed over 1,500 Australian adults with chronic non-cancer pain for four years – one of the longest studies of its kind. All used prescription opioids and about half tried using cannabis for pain, some occasionally and others daily or near daily.

Advocates of medical marijuana as a treatment for pain may be surprised by the findings.

In the Pain and Opioids IN Treatment (POINT) study, Gabrielle Campbell, PhD, and colleagues at the University of New South Wales found "no evidence that cannabis use improved patient outcomes.”

"At each assessment, participants who were using cannabis reported greater pain and anxiety, were coping less well with their pain, and reported that pain was interfering more in their life, compared to those not using cannabis," said Campbell, who was lead author of the study. "There was no clear evidence that cannabis led to reduced pain severity or pain interference or led participants to reduce their opioid use or dose."

These findings are not unique. Campbell was co-author of a recent review in the journal Pain that found that “evidence for effectiveness of cannabinoids in chronic non-cancer pain is limited.”  Cochrane reviews came to similar conclusions about cannabis for treating fibromyalgia and neuropathic pain.

In short, cannabis helps, but maybe not that much.

The POINT study would seem to contradict the 2017 National Academies of Sciences (NAS) report, which found “substantial evidence” that cannabis is an effective treatment for chronic pain, but in only five good-to-fair quality studies. Overall, the NAS report found that “cannabinoids demonstrate a modest effect on pain.”

About a third of the cannabis users in the POINT study reported reduced opioid use, but the prescription data showed that there was actually no difference.

The study also found that most cannabis users believed they were benefiting from cannabis, but there was no objective improvement in their pain scores.

“It is really difficult to disentangle the reasons for this,” Campbell told Cosmos. “One hypothesis is that it may improve sleep and subjective well-being.”

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This is consistent with other findings that cannabis doesn’t reduce pain, but helps people feel better. The book “A New Leaf: The End of Cannabis Prohibition” states that “patients often say that cannabis mostly disassociates them from the pain, like it’s placed in another room instead of eliminated.”

Similar results were obtained in an Oxford study, which found that “an oral tablet of THC, the psychoactive ingredient in cannabis, tended to make the experience of pain more bearable, rather than actually reduce the intensity of the pain.”

Masking pain may seem like a good thing. But as Grant Brenner, MD, points out in Psychology Today, believing that there is a benefit when there isn't one is problematic. Making pain more bearable may improve mood and sleep, but it could also lead patients to underestimate the significance of a serious health issue. This problem applies to many forms of pain management and requires further research.

“The illusion that a drug is helping with a condition when it is not can get in the way of seeking effective treatment and obtaining real relief,” said Brenner. “Rather than helping with actual pain, difficulty from pain, and need for opioid medication, cannabis consumption may lead people to believe they are improving when in reality they are not.

The POINT study found what many other studies have been finding about cannabis and chronic pain: Some people experience some benefits some of the time. But the study also has limitations. Participants had chronic pain severe enough to merit opioid therapy, so they may not be representative of people with chronic conditions in general. They also only had access to illicit cannabis that was not part of structured pain management program.

Still, as an editorial in The Age points out: "The findings do not mean medical cannabis does not merit a place in the treatment of various other ailments."

Cannabis and cannabis-derived pharmaceuticals like Epidiolex are proving useful for managing seizures, reducing chemotherapy side effects, and treating multiple sclerosis. There may yet be other uses to be discovered. For instance, cannabis may be effective for more rare disorders. And cannabis may be a viable add-on therapy or alternative for people who cannot tolerate or do not do well with conventional therapies.

The POINT study shows that cannabis is not a panacea for pain. Instead, cannabis is a drug, and we have to treat it with the respect we give any drug if we're going to learn how to use it effectively.

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Roger Chriss lives with Ehlers Danlos syndrome and is a proud member of the Ehlers-Danlos Society. Roger is a technical consultant in Washington state, where he specializes in mathematics and research.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.