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    clinical trial ibogaine

    Clinical Trial on Ibogaine for Opioid Dependence is Underway and Recruiting

    ICEERS | 2 November 2022

    Why the study

    ICEERS supports the development of evidence-informed policies and is committed to advancing clinical research. To support the collective knowledge on these topics, our organization launched the first-ever Phase II clinical trial in 2020 examining the efficacy of ibogaine for opioid dependence and detox from methadone. The number of people turning to ibogaine as a treatment option for various mental health conditions has been steadily increasing. There are many studies in the scientific literature that have examined the subjective effects of psychedelics, but few of them have been rigorously analyzed.1,2 

    Ibogaine has demonstrated promise for substance use disorders (SUDs), psychotherapy, and personal growth. But there is a difference between what anecdotal reports have shared and what can be replicated in a clinical environment. In addition, many ibogaine treatments are conducted “underground” and may not follow rigorous protocols to ensure the safety of the participant or collect valid results for later analysis.3 This study arose to fill this important gap to expand the collective knowledge base on the potential of ibogaine as a treatment option, in hope that it inspires the scientific community and supports sensible changes in policy.

    The current clinical trial came after years of engaging with the ibogaine medical subculture and the lessons learned from its experience. Our study is more than a clinical trial. It is the creation of a model that integrates ibogaine, state-of-the-art harm reduction, and SUD therapy that can inspire other centers to follow suit. The aim is to assure access to those who need it and not just those who can afford it.

    The main objective of this clinical trial is to evaluate the efficacy and safety of ibogaine for the treatment of methadone withdrawal. Researchers are also assessing the side effect profile of ibogaine and participants’ satisfaction with the treatment. The hope is that this study will serve as a basis to design safe, effective outpatient treatments for opioid withdrawal. The collection of qualitative data is essential to interpret the efficacy of ibogaine treatment.

    The clinical trial is linked with a larger strategic approach consolidated through our Iboga and Ibogaine Global Engagement Initiative, where we engaged with stakeholders in Gabon and internationally to envision a future for these medicines. 

    The clinical trial currently has 13 participants who were recruited from the Methadone Maintenance Program at the Hospital Universitari Sant Joan in Reus, Spain. This hospital is a pioneering center for harm reduction. The alliance with a University Hospital helps to open the possibility of ongoing research possibilities. Working in this hospital allowed us to create a highly specialized team with experience in the treatment of SUDs. In addition, two renowned cardiologists collaborated in the protocol design and are during the ibogaine sessions. The study is continuing to recruit participants, further details are below.


    Sustainably sourced ibogaine

    Ibogaine, which came into the spotlight as a potential treatment for SUDs, is only one of the many compounds found within iboga (Tabernanthe iboga). T. iboga (known as “sacred wood” by the people of Gabon) is now experiencing a rapid decline in the wild. This is due to the rising interest and demand for iboga and ibogaine leading to over-harvesting and illegal poaching. The majority of the ibogaine used by treatment providers comes from iboga. However, it can also be extracted from Voacanga africana, another African tree that is a more sustainable option.4

    The pursuit of a deeper understanding of traditional plant medicines via a scientific lens should not hinder these plants and their associated knowledge systems from continuing. Some of the sustainability concerns may be addressed by sourcing ibogaine from cultivated iboga (exported following the Nagoya Protocol), from V. africana, or through developing synthetic options. The ibogaine for the ICEERS clinical trial is sourced from Voacanga africana.

    Learn more about the study design and dosing protocol in our previous article on the clinical trial.


    How people are selected & what it entails

    All participants in the clinical trial must meet certain criteria to be enrolled. A preliminary interview is the first part of the selection process. All potential participants are screened for various criteria based on their physical and mental health. Study staff analyze their current medications to ensure there would be no contraindications with the clinical trial protocols.

    Approved participants can then begin the study. During the clinical trial, participants take their normal dose of methadone. Ibogaine is then administered in a supervised setting at the onset of opioid withdrawal symptoms. After ibogaine is given, half of the previous methadone dose is delivered when opioid withdrawal symptoms appear again. Then methadone doses are progressively reduced until no withdrawal symptoms arise. Further details of the dosing regime can be found here.

    When ibogaine is consumed in moderate or high doses, it may cause:

    • Changes in visual and auditory perception
    • Shifts in the perception of time and space
    • Fatigue, weakness
    • Nausea or vomiting
    • Dizziness
    • Tremors
    • Physical stimulation or nervousness

    The doses of ibogaine used in the study are low, so participants may not feel the previously mentioned effects. Some people describe ibogaine’s effects as comparable to psilocybin mushrooms, ayahuasca, or LSD.


    Open call for study participants

    The results of the study are ongoing, as the clinical trial is still in process. Based on the preliminary findings, ibogaine has demonstrated efficacy and safety for most participants thus far. The findings of the study will be published at the end of the trial.

    There are seven more open places in the study and the team is welcoming people internationally who may be interested. If you would like to get involved in this research, you can review the exclusion criteria of the study. If you checked the parameters and did not find anything that applies to you, you may be eligible to participate. 

    Interested parties would need to spend up to two months in Reus, Spain to complete the ibogaine treatment. The process involves weekly ibogaine administration (six weeks in total) plus one additional week to review the participant’s health. A complete blood analysis and an EKG would need to be done before traveling to Reus for the study. All participants must stop taking any drugs for the duration of the clinical trial, other than methadone by prescription.

    The participants stay at the hospital on the days ibogaine is administered. They would need to find nearby accommodation for the duration of their time in Spain. Participants from overseas would need to pay for their airfare and all travel and accommodation costs.

    Participation in this study is completely voluntary throughout the entire process. People can decide to not participate or withdraw from the study at any time. The personal data of all study subjects will be kept strictly confidential and comply with the provisions of the EU General Data Protection Regulation.

    If you are interested in participating in the first ibogaine clinical trial for opioid dependence, please reach out here.


    Further reading


    Thank you to the study’s generous supporters:


    The ibogaine study relies on contributions from the public to continue. Please consider supporting our research.



    1. Kohek, M., Ohren, M., Hornby, P., Alcázar‐Córcoles, M. Á., & Bouso, J. C. (2020). The ibogaine experience: A qualitative study on the acute subjective effects of ibogaine. Anthropology of Consciousness, 31(1), 91-119.
    2. Ona, G., Rocha, J. M., Bouso, J. C., Hallak, J. E., Borras, T., Colomina, M. T., & Dos Santos, R. G. (2021). The adverse events of ibogaine in humans: an updated systematic review of the literature (2015–2020). Psychopharmacology, 1-11.
    3. International Center for Ethnobotanical Education, Research, and Service. (2020). Deciding to Take Iboga or Ibogaine. Accessed on October 26, 2022.
    4. International Center for Ethnobotanical Education, Research, and Service. (2020). Iboga and Ibogaine Community Engagement Initiative Phase 1 Report. Accessed on October 26, 2022.


    Photo by CDC on Unsplash.

    Categories: Ibogaine clinical trial , NEWS
    Tags: drug dependence , methadone , addiction treatment , substance use disorders , withdrawal , opium , Tabernanthe iboga