Ayahuasca-Assisted Therapy for Addiction : Results from a Preliminary Observational Study in Canada, Gerald Thomas et al., 2013

Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada

Gerald Thomas, Philippe Lucas, N. Rielle Capler, Kenneth W. Tupper and Gina Martin

Current Drug Abuse Reviews, 2013, 6, (1), 1-13.



Introduction : This paper reports results from a preliminary observational study of ayahuasca-assisted treatment for problematic substance use and stress delivered in a rural First Nations community in British Columbia, Canada.

Methods : The “Working with Addiction and Stress” retreats combined four days of group counselling with two expert-led ayahuasca ceremonies. This study collected pre-treatment and six months follow-up data from 12 participants on several psychological and behavioral factors related to problematic substance use, and qualitative data assessing the personal experiences of the participants six months after the retreat.

Findings : Statistically significant (p < 0.05) improvements were demonstrated for scales assessing hopefulness, empowerment, mindfulness, and quality of life meaning and outlook subscales. Self reported alcohol, tobacco and cocaine use declined, although cannabis and opiate use did not; reported reductions in problematic cocaine use were statistically significant. All study participants reported positive and lasting changes from participating in the retreats.

Conclusions : This form of ayahuasca-assisted therapy appears to be associated with statistically significant improvements in several factors related to problematic substance use among a rural aboriginal population. These findings suggest participants may have experienced positive psychological and behavioral changes in response to this therapeutic approach, and that more rigorous research of ayahuasca-assisted therapy for problematic substance use is warranted.

Keywords:  addiction, ayahuasca, cocaine, substance dependence, substance use, harm reduction.



Ayahuasca is a psychotropic brew prepared from the Amazonian vine Banisteriopsis caapi and leaves of the bush Psychotria viridis. These plants contain, respectively, harmala alkaloids and dimethyl-tryptamine (DMT), which when ingested in combination orally induce several hours of a dream-like altered state of consciousness characterized by intense visual, auditory, ideational and emotional effects [1, 2]. The presumed biochemical mechanism of action for ayahuasca brews includes presence of beta-carboline monoamine oxidase inhibitors (harmala alkaloids) coupled with dimethyltryptamine, a compound that acts on specific serotonin receptors, particularly 5-HT2A receptors [3, 4]. Ayahuasca has traditionally been drunk in ritual contexts by Amazonian indigenous and mestizo peoples for a variety of divinatory, magical, spiritual, aesthetic and other cultural purposes, including as a diagnostic aid and herbal remedy in folk healing practices [5]. In the late 20th and early 21st centuries, ayahuasca drinking became a transnational phenomenon through increased tourism to the Amazon, ceremonies regularly conducted by itinerant ayahuasqueros (i.e., individuals trained to administer ayahuasca within an
Amazonian folk healing ritual context) in the global North, and a few Brazilian ayahuasca religions establishing active spiritual communities in countries around the world [6, 7].

The transnational expansion of ayahuasca has been accompanied by growing scientific interest in the brew’s potential therapeutic or salutogenic value. Preliminary research has shown ayahuasca has promise for alleviating some mental disorders and for providing other long-term health and social benefits among regular drinkers of the brew in ritualized and religious community contexts [4, 8-11].
Importantly, the ritual use of ayahuasca does not typically produce health or psychosocial problems such as addiction [12-14]. Rather, ceremonial ayahuasca drinking has been correlated with lower amounts or severities of substance dependence. For example, Grob et al. [9] found that among a randomly selected group of União do Vegetal (or UDV, a Brazilian ayahuasca church) members, a majority reported a prior history of moderate to severe problems with alcohol or other drugs, but all had stopped using substances other than ayahuasca (including tobacco) after joining the church and attributed their improved health
behaviors to ayahuasca drinking. The UDV subjects also reported less excitability and impulsivity, and more confidence and optimism compared with matched-control community members who did not use ayahuasca [9]. Fábregas et al. [13] examined addiction severity among 56 people belonging to two different Brazilian ayahuasca churches (UDV and Santo Daime), and found higher lifetime illicit drug use but lower past-month use of alcohol and no use of psychoactive drugs other than ayahuasca and cannabis in the last 30 days, compared with matched controls from the community. In interviews with 32 members of a U.S.-based chapter of the Santo Daime church, Halpern et al. [10] found that, of 24 who reported past substance abuse or dependence, all but two were in sustained remission and all five with
prior alcohol dependence attributed their recovery to participation in the church’s rituals. However, all these studies involve subjects who are regular and committed members of religious communities, so it remains unclear whether fewer reported substance use problems can be attributed to the ayahuasca drinking rather than being a church member.

The use of ayahuasca as a remedy to help overcome drug addictions is a fundamental aspect of treatment programs at Takiwasi, a therapeutic community based in Tarapoto, Peru [15]. The Takiwasi approach incorporates various aspects of traditional Amazonian folk medicine (including the use of various medicinal jungle plants, in addition to ayahuasca), communitarian residence and psychotherapy. Similarly, in the state of Amazonas, Brazil, the Instituto de Etnopsicología Amazónica Aplicada (or IDEAA) runs a treatment program that combines the ritual use of ayahuasca with complementary psycho-social rehabilitation methods [16]. Although these programs claim improved health outcomes for patients who complete them, neither has been evaluated with sufficient scientific rigor to provide definitive evidence of the success of their approaches. Nevertheless, evidence from members of Brazilian ayahuasca churches, as well as claims of treatment success from Takiwasi and IDEAA, has led researchers to speculate on possible neurochemical, psychological or transcendent mechanisms of ayahuasca’s purported therapeutic action [3, 4, 17, 18].

In Canada, First Nations and Aboriginal peoples have been disproportionately affected by illnesses and social problems that are the legacies of colonialism and consequent territorial and cultural dislocation [19], including substance dependence (although considerable variation in epidemiology of addiction exists across this heterogeneous sub-population) [20]. However, current approaches to treating addictions—especially to alcohol and cocaine— continue to be of limited success [21], despite decades of research. Dr. Gabor Maté, a Canadian physician specialized in addictions medicine and experienced in working with Aboriginal people [22], became interested in the potential value of ayahuasca as an adjunct to group therapy in 2009.

He began conducting occasional multi-day “Working with Addiction and Stress” retreats in partnership with ayahuasqueros from Peru and British Columbia (the retreat team), reporting positive outcomes for participants from the general Canadian population with a variety of psychological health conditions and illness severities. The retreat team refined the structure, pacing and other elements of their approach over the course of several retreats conducted with mostly non-aboriginal Canadian participants in 2009 and 2010. This allowed the retreat team to establish procedures for enhancing interpersonal rapport and creating a coherent therapeutic context prior to the sessions conducted with the First Nations participants observed in this study.

The retreat team’s work with ayahuasca came to the attention of a rural aboriginal First Nations band in
southwestern British Columbia, which invited the team to conduct retreats for community members with substance dependence or other habitual behavioral problems, such as problem gambling. The band’s health office was interested in exploring whether a traditional indigenous practice from South America might help address some of the past trauma and consequent health issues that its community members
were experiencing and that Western medical and legal approaches have not been reliably effective at curtailing.

Following the decision to provide this treatment to members of the community, the band’s health office offered the authors of this article (the research team) an opportunity to conduct an observational study of the retreats in order to more systematically document and assess the effects of the treatment. Funding for the study was secured through philanthropic donations to the Multidisciplinary Association of Psychedelic Studies (MAPS) and through an anonymous donor. In February 2011, members of the research and retreat teams met with the band Council and band Elders to discuss the retreats and obtained their consent for the study. At the request of the band leadership, the band’s health office agreed to closely monitor participants for any adverse psychological or other reactions following the retreats. Subsequently, two retreats were conducted, one in June 2011 and the other in September 2011.