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Simon Fraser University (SFU) researchers have found that recent psychedelic use was associated with 55 percent reduced odds of daily opioid use. It is the first longitudinal study of its kind and adds to growing knowledge and interest in the use of psychedelics—such as psilocybin, LSD, ayahuasca and others—in addition to counselling for harm reduction and treatment of substance use disorders.

SFU School of Public Policy Professor Kora DeBeck is a research scientist with the B.C. Centre on Substance Use (BCCSU). She specializes in longitudinal cohort methodologies, and innovative approaches to health and policy interventions to reduce harm among people who use drugs. DeBeck is the principal investigator of the At-Risk Youth Study (ARYS), an ongoing cohort study of more than 900 high-risk, drug-using street youth in Vancouver. 

SFU Health Sciences Professor Kanna Hayashi is the St. Paul's Hospital Chair in Substance Use Research and a research scientist at BCCSU. Her research expertise includes epidemiology, community-based research, public health and human rights, substance use, and health services for drug-using populations. She currently leads the Vancouver Injection Drug Users Study (VIDUS), one of the longest-running cohort studies of more than 1000 people who inject drugs in Vancouver.

DeBeck and Hayashi collaborated with researchers from the University of British Columbia and the BCCSU to follow 3800 participants over 12 years who reported on their use of opioids as well as their use of various psychedelics. The research team published their findings, Psychedelic use is associated with reduced daily opioid use among people who use illicit drugs in a Canadian setting, in a recent issue of the International Journal of Drug Policy.

While more studies are needed to investigate and understand the therapeutic potential of psychedelics, these findings point towards novel and holistic treatments for substance use disorders.

We spoke with DeBeck and Hayashi about their research.

Based on study responses, why do you think psychedelics seem to reduce the use of daily opiates?

Our study is based on observational data so we are not able to decipher why earlier psychedelic use was associated with a reduced risk of daily opiate use. There is growing evidence from clinical trials of psychedelic-assisted therapy for substance use disorders that hypothesizes that there are neurobiological mechanisms (i.e., activation of 5-HT2A serotonin receptors) that influences specific areas of the brain responsible for modulating mood, states of consciousness and potentially habitual behaviors. Abnormal serotonin neurotransmission is linked to many aspects of drug dependence, such as cravings.

In addition to proposed biological mechanisms, the spiritual components often referred to as mystical-type experiences are thought by some to mediate therapeutic impacts, significantly correlated with positive substance use recovery outcomes.

Prior evidence indicates that psychedelics may also facilitate pro-social behaviors and enhance one’s sense of connectedness to self, others and the natural world.

In sum, we do not know for certain why there is an association between psychedelic use and reduced likelihood of subsequent daily opiate use. We really need further research and confirmation in other settings to determine the therapeutic potential of psychedelics for opioid use disorder.

Your study reports on the naturalistic use of psychedelics as opposed to clinical use. What does this mean?

Our study is observational in nature and relies on participants telling us about their prior experiences with different substances. We have no control over the contexts, doses or frequency of the psychedelic use they report. Study participants may not have used psychedelics with therapeutic intent.

Are policy-makers close to approving psychedelics as a treatment for opiate use disorders? What is next in this area of research?

Both psilocybin-assisted therapy and MDMA-assisted therapy have been designated “breakthrough therapy status” for treatment-resistant depression and post-traumatic stress disorder (PTSD), respectively by the U. S. Federal Drug Administration. These therapies are becoming more widely available through compassionate use pathways and legal exemptions in Canada. For instance, Health Canada's special access program has recently been amended to allow practitioners to apply to use psychedelics with their patients on a case-by-case basis for mental health and substance use disorders. 

As researchers in Public Policy and Health Sciences, how did your collaboration begin and how has the cross-disciplinary approach informed your respective research areas?

We met as graduate students over 10 years ago at the B.C. Centre for Excellence in HIV/AIDS and have been collaborating on policy-oriented substance use research together ever since. Our shared core values of centering the key populations that we serve to generate research evidence that advances social justice and equity continues to guide our collaborations. Conducting and mobilizing research evidence to inform public policies and services that improve the health and well being of people who use drugs is by nature interdisciplinary. By drawing on our unique training and disciplinary strengths we are always seeking to drive research and policy innovation and bring change to an area in desperate need of reform.  

This study was supported by the U.S. National Institutes of Health, the Canadian Institutes of Health Research and Michael Smith Health Research B.C.

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