A newly published study, combining a literature review and a survey of U.S. college students, concludes that medical marijuana may be an effective tool in mitigating the harms of opioid use disorder, while noting that "understanding and knowledge vary widely.

The new paper states: "Through a review of the literature, we can reasonably conclude that medical marijuana has some efficacy in opioid maintenance therapy and other therapeutic uses." Given public concerns about opioid overdose and the potential for cannabis to be rescheduled, the paper adds, "The use of medical marijuana is likely to increase in a harm reduction model."

The review begins by examining the available evidence on the use of medical cannabis as an alternative to opioids and other medications, and notes that at least some research suggests that cannabinoids can help reduce opioid-related cravings and withdrawal symptoms. The study also notes that self-reported data suggest that some individuals have reduced their use of opioids in favour of medical cannabis.

"Current research indicates that medical marijuana holds significant promise for reducing harms associated with opioids and as a substitution therapy," states Professor Clark Florn in his master's thesis at Augsburg University.

"Medical marijuana has demonstrated the ability to enhance the analgesic effects of opioids while reducing patient tolerance and dependence. There is substantial evidence supporting the efficacy of medical marijuana as a substitute for illicit and pharmaceutical opioids. Cannabinoids have been shown to alleviate opioid withdrawal symptoms in animal models, and anecdotal evidence suggests similar effects in humans."

"Therefore, medical marijuana has the potential to reduce adverse effects and decrease drug-seeking behaviors among individuals struggling with opioid addiction. A substantial body of existing evidence supports the theory that medical marijuana can effectively reduce opioid-related harms in the community."

The paper acknowledges the inherent risks associated with cannabis smoking, but also notes that these risks are complex and often vary from person to person. For instance, the paper states that some individuals may use medical cannabis to manage depression, while "for others, cannabis smoking may precede the onset of depression."

"Therefore, we need to understand this drug and its nuances," said Professor Florn, noting that "clearly, more research is needed" to understand how the substance can be "beneficial" for some people but "extremely harmful" for others.

"However, the paper notes that, overall, the risks associated with medical marijuana are significantly lower than those of opioids. 'While medical marijuana may have some associated harms, the harms appear to be much smaller than those of opioids,' the report states. 'Therefore, medical marijuana has the potential to improve patient lives and offer better treatment outcomes compared to current opioid substitution/maintenance treatment models.'"

Despite record numbers of opioid-related deaths over the years, the study asserts that "treatment approaches have not changed, and there has been little pharmacological progress in interventions for opioid addiction. In fact, people with opioid use disorder who receive treatment face mortality rates up to 12 times higher than the general population."

Meanwhile, methadone, an adjunctive therapy medication used to treat opioid use disorder, is often associated with side effects such as ‘sleep difficulties, problems with sexual functioning, and cardiovascular events.’

The paper argues that many people should ‘detoxify and taper off the drug, which is the purpose of a maintenance programme’, but because subjects ‘report improvements in quality of life’, researchers and policy makers often ‘ignore the adverse events and side effects of long-term methadone use’. overlook the adverse events and side effects of long-term methadone use.’

The results of the survey portion of the new paper generally suggest that medical marijuana may be a promising tool for treating opioid use disorder.

More than 70 per cent of respondents indicated that they believed that opioids were more harmful than medical cannabis, and the same proportion indicated that medical cannabis could be used for both pain management and opioid withdrawal symptoms.

At the same time, about 65 per cent said they knew someone who had used medical marijuana in the past year for ‘non-described use’ medical purposes. Notably, about two thirds of respondents answered that they believed medical cannabis had a positive impact on mental health.

Overall, eight in ten respondents said marijuana should be legalised.

"Trends in the literature suggest that marijuana has fewer side effects and fewer long-term health effects than opioids," the study said. "The majority of participants believe that opioids are more harmful, which was the impetus for the study, and the findings reflect the conclusions of the literature."

"Medical marijuana has been shown to alleviate pain, and a growing body of evidence suggests a symbiotic relationship between cannabinoid and opioid receptors," the report continues. "The student cohort appears to be educated about the use of medical marijuana in pain management contexts, reflecting the extensive literature on medical marijuana applications in cancer, chronic pain, and even palliative care."

Professor Florn acknowledges that current research on medical marijuana and opioids is "relatively small and often limited," but "researchers believe that data will explode in the coming years as public attitudes toward cannabis change and as the possibility of federal reclassification of cannabis looms."

The paper states, "In fact, the proven efficacy of medical marijuana in pain management and cancer treatment, coupled with its other uses/benefits and remarkably safe side effect profile, make it an excellent candidate for further exploration in addiction research." Just months prior to the release of this study, an independent, federally-funded study found that medical  marijuana could help patients with substance use disorders avoid or reduce opioid use, maintain treatment, and manage withdrawal symptoms.

Researchers at the University of Southern California have embarked on a study to investigate the relationship between cannabis consumption and injected opioid use. They recruited 30 patients from community sites near a syringe exchange program and a methadone clinic in Los Angeles to analyze this relationship.

The researchers found that "Participants reported using cannabis as a substitute or in conjunction to manage the pain of withdrawal symptoms, such as physical aches and overall discomfort, and that they reduced the frequency of injecting opioids."

The study, published in the journal Drug and Alcohol Dependence Reports, was funded in part by the National Institute on Drug Abuse (NIDA) and supports a large body of scientific literature that suggests that the use of medical marijuana can offset the harms of the opioid epidemic, either by helping people limit their use or by achieving complete freedom from it.

Another recent study in Ohio found that the vast majority of medical marijuana patients in the state reported that marijuana reduced their use of prescription opioid painkillers, as well as other illicit drugs.

Another recent report published in BMJ Open compared the effects of medical cannabis and opioids in treating chronic non-cancer pain, finding that medical cannabis "may have similar effects and may lead to fewer treatment discontinuations compared to opioids," suggesting it could provide similar relief with a lower risk of side effects.

A federally funded study published in May concluded that even cannabis terpenes may have analgesic properties. The study found that injected doses of the compound produced "roughly the same" reduction in pain markers in mice compared to low-dose morphine. However, when the two drugs were combined, terpenes appeared to enhance the efficacy of morphine in mice.

Another study published late last year found that medical cannabis and opioids were "equally effective" in reducing pain intensity, and that medical cannabis could provide more "holistic" relief, such as improved sleep, attention, and mood.

In the same month, a study published in the Journal of Dental Research showed that pure CBD could alleviate acute dental pain, with results comparable to those of commonly used dental opioid formulations.

A study published last summer indicated that the use of medical cannabis could decrease pain levels and reduce reliance on opioids and other prescription medications. A separate study published by the American Medical Association in February found that chronic pain patients who used medical cannabis for more than a month significantly reduced their prescription opioid use.

According to another report released last year by the American Medical Association, about one-third of chronic pain patients report using medical marijuana as a treatment option. The majority of that group said they use medical marijuana as an alternative to other painkillers, including opioids.

Other studies published last year also found that allowing people to legally purchase CBD significantly reduced opioid prescription rates, resulting in a 6.6 to 8.1 percent reduction in opioid prescriptions.

Meanwhile, a 2022 research paper analysed data on prescription drugs in Medicaid and found that the legalisation of medical cannabis for adult use was associated with ‘significant reductions’ in the use of prescription drugs to treat a wide range of conditions.