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    ayahuasca adverse effects efectos adversos ICEERS study estudio

    Global Ayahuasca Survey Results Published on Adverse Effects


    Ayahuasca has become increasingly well-known throughout the world for supporting mental health and spiritual and personal growth. Although clinical trials and observational studies have examined the potential benefits of ayahuasca, few have analyzed its adverse effects. ICEERS has done extensive research on the potential benefits of ayahuasca and, through that, we also look at adverse outcomes. A broader picture of the ayahuasca experience will support people working with it and assist policymakers with their decisions on future regulations and responses to public health.

    In light of this, ICEERS and colleagues have published a new paper offering the most detailed report thus far on the topic, Adverse Effects of Ayahuasca: Results from the Global Ayahuasca Survey in the open-access journal PLOS Global Public Health. This new paper puts the potential adverse impacts of ayahuasca in context and details the variables that influence them. This analysis helps to pinpoint when and how adverse effects are experienced to help inform best practices and understand how participants perceive them. This study was conducted with a sample of more than 10,000 subjects from more than 50 different countries.

    The paper, authored by José Carlos Bouso of ICEERS and colleagues, used data from the Global Ayahuasca Survey carried out between 2017 and 2019. The Global Ayahuasca Survey was done in collaboration with the University of Melbourne and translated into six languages. The survey was the first with a university affiliation that examined people who had experiences with ayahuasca. Those respondents who had worked with ayahuasca were asked a series of questions on its adverse effects. This information has been the foundation for a line of subsequent studies examining this plant medicine. Results of this survey have been published in other papers, demonstrating that ayahuasca may be beneficial for drug and alcohol use, anxiety and depression, and general well-being. Any potential adverse effects would need to be understood in the context of these reported benefits.

    This new paper reports that while there are potential adverse physical and challenging psychological effects from ayahuasca, they are generally not detrimental. Some of the effects that were described as adverse by researchers were not perceived as such by many participants, who often regard them as an integral part of the healing process. Researchers found that participants view them as part of the process and that the benefits outweigh any adverse effects. 

    New Paper Expanding on Earlier Research

    This recent paper builds on findings from ten years ago in ICEERS’ first-ever paper “Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study” (2012) that was also published by the PLOS group. It remains the largest study to date evaluating neuropsychological performance and mental health. The sample compared 130 regular participants (who on average had been drinking ayahuasca monthly for more than 10 years) to controls. This research demonstrated the long-term safety of ayahuasca on cognitive function and mental health. 

    These findings were then built upon using neuroimaging techniques that were published in “Long-term use of psychedelic drugs is associated with differences in brain structure and personality in humans” (2015). The paper demonstrated the impact of ayahuasca on neuroplasticity for the first time. This data laid the groundwork for further research and a deeper analysis of how ayahuasca impacts people’s health and well-being.

    Latest Findings on Potential Adverse Effects

    Expanding on the data from previous investigations, the authors of this newly released study found that ayahuasca has notable, although rarely severe, adverse effects. Information was collected on the participants’ age, physical and mental health history, and context of ayahuasca consumption. Only 2.3% of participants reported adverse physical effects requiring medical attention. Overall, acute physical health adverse outcomes were reported by 69.9% of the sample. The most common occurrences were nausea and vomiting (68.2% of participants), headache (17.8%), and abdominal pain (12.8%). Throughout the paper, the authors explain that nausea and vomiting, while considered adverse in relation to prescription drugs, are intended effects in the context of traditional Amazonian medicine. They are associated with healing and spiritual cleansing as opposed to harm. 

    Overall, 87.6% of the respondents reporting adverse effects believed they were part of a positive growth process. Fifty-five percent (55%) of participants reported adverse mental health impacts. They included seeing or hearing things (28.5%), feeling disconnected or alone (21.0%), and having nightmares or disturbing thoughts (19.2%). The authors also identified several factors that predispose people to adverse physical events. These included older age, having a physical health condition or substance use disorder, and taking the medicine in a non-supervised setting. 

    The authors observed that ayahuasca has notable, although rarely severe, adverse effects according to the standards used for assessing prescription medicines. They stated that ayahuasca practices cannot accurately be evaluated with the same parameters as prescription medicines. This is due to the complexity of the ayahuasca experience, which includes potential challenges intrinsic to the experience, some of which are considered part of the healing process (such as nausea and vomiting). Upcoming research initiatives will continue to shed light on the best ways to analyze the effects of ayahuasca and how to develop better practices for improved health and well-being.

    “In sum, the international expansion of ayahuasca practice creates a series of new challenges for global public health policy and regulation. These include: 1) the intrinsic cultural complexity of making policy decisions in the absence (typically) of representatives with traditional knowledge; 2) the consideration of such healing practices based on the standards of biomedical medicine and its practices, where safety and efficacy do not necessarily refer to the same physical and psychological processes; and, 3) the possible recognition of such practices as therapeutic tools for self-care and mental health treatment in a globalized world, where instead of exporting medical systems cultures are importing them. The case of ayahuasca seems a paradigmatic example of how Western countries are trying to incorporate medical knowledge from other cultures into their informal self-healing practices. It will be necessary to approach all these challenges will with open dialogue between different academic perspectives and epistemologies where traditional knowledge can dialogue with the scientific community.”

    What’s on the Horizon

    This is the first paper in a series of two exploring adverse effects. The same research team will build upon this information in a forthcoming second study drawing on the Global Ayahuasca Survey data. The following paper will conduct extensive analysis on the variables playing a role in possible adverse occurrences with ayahuasca. Researchers will use models based on structural equations (a statistical method of data analysis) to find the commonality between those experiencing potential adverse effects. 

    Future updates on the next paper will be available on our website. In the meantime, you may read the latest research and other papers of interest below. 


    Read the study


    Further Resources & Papers of Interest


    Photo by Benjamin De Loenen.

    Categories: NEWS , Ayahuasca , RESEARCH & INNOVATION
    Tags: ayahuasca , scientific research , study , adverse effects , traditional medicine