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Genís Ona

Sociedad Española de Medicina Interna, Institut de Recerca Biomèdica Catalunya Sud

41 papers in the library · 740 citations · publishing 0-2026

Papers

Effects of ayahuasca on mental health and quality of life in naïve users: A longitudinal and cross-sectional study combination

Scientific Reports March 5, 2020 José Carlos Bouso, Daniel Jiménez‐garrido, María de Lourdes Gómez-sousa et al. 111 citations

Ayahuasca, a hallucinogenic decoction used in traditional Amazonian medicine, may have therapeutic benefits for psychiatric disorders. In a study of 40 first-time users, nearly half (45%) initially met criteria for a psychiatric disorder; after ayahuasca use, more than 80% of those showed clinical improvements that persisted at 6 months. Questionnaires indicated significant reductions in depression and psychopathology. Long-term users (n=23) had lower depression scores and higher self-transcendence and quality of life compared to first-time users. The authors suggest further controlled and observational studies are warranted to assess risks and benefits.

Ayahuasca and Public Health: Health Status, Psychosocial Well-Being, Lifestyle, and Coping Strategies in a Large Sample of Ritual Ayahuasca Users

Journal of Psychoactive Drugs February 7, 2019 Genís Ona, Maja Kohek, Tomàs Massaguer et al. 76 citations

Long-term ayahuasca use in community settings is linked to better self-reported health and healthier lifestyles. A survey of 380 regular users in Spain found that 56% reduced their prescription drug use after starting ayahuasca. Those who had used ayahuasca more than 100 times scored higher on measures of personal values. The authors conclude that respectful, controlled use of psychedelic drugs in group settings can benefit public health.

Potential safety, benefits, and influence of the placebo effect in microdosing psychedelic drugs: A systematic review

Neuroscience & Biobehavioral Reviews October 5, 2020 Genís Ona, José Carlos Bouso 59 citations

Microdosing psychedelic drugs like LSD or psilocybin is increasingly common in Western societies, primarily for enhancing mood or creativity. This systematic review of human studies examined efficacy, safety, and the role of placebo effects. The evidence shows strengths such as large sample sizes and robust methods, but also limitations like gender bias and inconsistent dosing. Results are highly contradictory, with some studies reporting benefits and others reporting detriments to mood, creativity, and energy. The review offers an overview of methods to guide future research.

Cross-Sectional Associations Between Lifetime Use of Psychedelic Drugs and Psychometric Measures During the COVID-19 Confinement: A Transcultural Study

Frontiers in Psychiatry June 16, 2021 Dóra Révész, Genís Ona, Giordano Novak Rossi et al. 42 citations

During the first strict COVID-19 lockdown (April–July 2020), people who had used psychedelic drugs regularly (more than once per six months) reported less psychological distress, less peritraumatic stress, and more social support than occasional or non-users. Regular users also scored higher on novelty-seeking and self-transcendence and lower on cooperativeness. The findings suggest that lifetime psychedelic use may be a protective factor for mental health under stressful confinement, or that pre-existing personality traits make some individuals more likely to use psychedelics. The study surveyed 2,974 English, Portuguese, and Spanish speakers online.

The adverse events of ibogaine in humans: an updated systematic review of the literature (2015-2020).

Psychopharmacology June 1, 2022 Genís Ona, Juliana Mendes Rocha, José Carlos Bouso et al. 41 citations

Ibogaine, a hallucinogenic and psychostimulant alkaloid from the African shrub Tabernanthe iboga, is known for its anti-addictive properties, but its use is associated with serious adverse events and fatalities. A systematic review of 18 studies from 2015 to 2020 found highly heterogeneous results regarding the product used and dosages. Adverse events were classified as acute effects (within 24 hours) and persistent cardiac, psychiatric, and neurological alterations. The review highlights the need for phase I clinical trials to establish safety for standardized ibogaine products, and for research to identify vulnerable populations and develop effective screening and clinical procedures.

Communalistic use of psychoactive plants as a bridge between traditional healing practices and Western medicine: A new path for the Global Mental Health movement.

Transcultural psychiatry October 1, 2022 Genís Ona, Ali Berrada, José Carlos Bouso 28 citations

The Global Mental Health movement seeks to expand mental health treatment in low- and middle-income countries, but debates persist about how best to serve diverse cultures. Beyond biomedical interventions, complementary approaches should emphasize social and community aspects. Many cultures have traditional rituals involving communal use of psychoactive plants, which should be respected and promoted as valuable tools for community-level mental health care. These practices foster community engagement, are relatively affordable, and respect local worldviews. Their medical systems can be explained biomedically, and recent clinical trials show therapeutic potential. Psychoactive plants and associated rituals offer benefits as complementary mental health services.

An international Delphi consensus for reporting of setting in psychedelic clinical trials.

Nature medicine June 3, 2025 Chloé Pronovost-Morgan, Kyle T. Greenway, Leor Roseman et al. 26 citations

A Delphi consensus study with 89 experts from 17 countries identified 30 extra-pharmacological variables that are important or very important for reporting the setting in psychedelic clinical trials. These variables, forming the ReSPCT guidelines, cover physical environment, dosing session procedure, therapeutic framework and protocol, and subjective experiences. The findings reveal significant ambiguities in current conceptualizations of set and setting. The guidelines provide a new standard for designing and documenting contextual factors in psychedelic research.

Inside bad trips: Exploring extra-pharmacological factors

Journal of Psychedelic Studies March 21, 2018 Genís Ona 26 citations

Bad trips—adverse reactions to psychedelic drugs—are linked to recreational use, consumption in large outdoor spaces, and inexperience with the drug. Mixing drugs, ignorance about purity or dosage, and other problems that may contribute to bad trips can be addressed through harm-reduction strategies. However, a causal connection cannot be established from this descriptive, web-based survey of volunteers who had previously experienced a bad trip. Prospective studies with larger samples are needed to clarify the role of extra-pharmacological factors.

Ayahuasca and Public Health II: Health Status in a Large Sample of Ayahuasca-Ceremony Participants in the Netherlands

Journal of Psychoactive Drugs May 28, 2022 Maja Kohek, Genís Ona, Michiel van Elk et al. 25 citations

Regular participation in ayahuasca ceremonies is not linked to relevant health harms. Compared to normative Dutch data, 377 participants (50.1% women, mean age 48.8 years) showed better general well-being, fewer chronic or lifestyle-related diseases, more physical activity, and a more balanced diet. During the COVID-19 pandemic, they used less alcohol. Although they used more illegal drugs than the general population, they did not report associated harms. This evidence could inform drug policymakers in developing evidence-based public policies.

Acute Psychological Adverse Reactions in First-Time Ritual Ayahuasca Users: A Prospective Case Series.

Journal of clinical psychopharmacology María Gómez-sousa, Daniel F Jiménez-garrido, Genís Ona et al. 24 citations

Among 40 first-time ayahuasca ceremony participants, 7 reported intense challenging psychological effects. Four of those 7 had a pre-existing psychiatric diagnosis; one month after the ceremony, two no longer met diagnostic criteria and the other two showed considerably reduced symptoms, with effects persisting at six months. Poor setting and guidance contributed to some reactions. Six of the seven did not use ayahuasca again during the study. The findings suggest that acute negative psychological reactions during ayahuasca ceremonies can sometimes be followed by positive long-term effects, highlighting the need for prospective research on safety and contextual factors.

Main targets of ibogaine and noribogaine associated with its putative anti-addictive effects: A mechanistic overview.

Journal of psychopharmacology (Oxford, England) December 1, 2023 Genís Ona, Ingrid Reverte, Giordano N Rossi et al. 20 citations

Ibogaine and its main metabolite, noribogaine, modulate several brain targets associated with substance use disorders. Rather than having a single key mechanism, their anti-addictive action appears to arise from a complex modulation of multiple receptor systems, creating potential beneficial synergies. This understanding comes from a review of theoretical and experimental studies published up to July 2022. The authors suggest that future research should apply polypharmacology approaches to better describe the multifaceted patterns of this multi-target drug, which could guide both mechanistic and therapeutic studies.

Effects of ayahuasca on the endocannabinoid system of healthy volunteers and in volunteers with social anxiety disorder: Results from two pilot, proof‐of‐concept, randomized, placebo‐controlled trials

Human Psychopharmacology Clinical and Experimental February 2, 2022 Rafael G. Dos Santos, Juliana Mendes Rocha, Giordano Novak Rossi et al. 20 citations

A post-hoc analysis of two small randomized placebo-controlled trials measured endocannabinoid (anandamide, AEA; 2-arachidonoylglycerol, 2-AG) plasma levels in healthy volunteers and in volunteers with social anxiety disorder (SAD) after a single oral dose of ayahuasca or placebo. In the SAD group, ayahuasca intake was associated with a significant difference in AEA concentrations over time, and near-significant increases in AEA were observed at 90 and 240 minutes after intake. No definitive conclusions could be drawn due to high interindividual variability and small sample sizes. Larger studies are needed to clarify ayahuasca's effects on the endocannabinoid system.

Exploring 5-MeO-DMT as a pharmacological model for deconstructed consciousness.

Neuroscience of consciousness January 1, 2025 Christopher Timmermann, James W Sanders, David Reydellet et al. 19 citations

The psychedelic 5-MeO-DMT can, in its most extreme cases, produce a complete absence of self-experience and other perceptual content while preserving a quality of aroused, waking awareness. In an exploratory observational study in naturalistic ceremonial settings, micro-phenomenological interviews, questionnaires, and EEG recordings revealed a dynamic progression of effects, including variable disruptions of bodily and narrative self, reduced phenomenal distinctions, and visual imagery. EEG showed global alpha and posterior beta power reductions, suggesting inhibition of top-down brain models. The findings indicate 5-MeO-DMT's potential as a pharmacological model for deconstructed consciousness, though retrospective questionnaires have limitations.

Underground ibogaine use for the treatment of substance use disorders: A qualitative analysis of subjective experiences.

Drug and alcohol review February 1, 2023 Borja J Rodríguez-cano, Maja Kohek, Genís Ona et al. 17 citations

Ibogaine, a psychoactive alkaloid from the Tabernanthe iboga plant traditionally used in Bwiti culture, has been used experimentally to treat substance use disorders (SUD) since 1962. Interviews with 13 people who self-treated their SUD with ibogaine revealed that the drug's therapeutic benefits arise not only from its pharmacology but also from the subjective experience it induces. Participants reported that ibogaine evoked interpersonal and transpersonal experiences, autobiographical memories, and personal insights. These effects, along with preparation, integration, and motivation for lifestyle change, appear to help individuals cope with their SUD, particularly given limited alternative treatment options.

The Kappa Opioid Receptor and the Sleep of Reason: Cortico-Subcortical Imbalance Following Salvinorin-A.

The international journal of neuropsychopharmacology January 12, 2022 Genís Ona, Frederic Sampedro, Sergio Romero et al. 17 citations

Kappa opioid receptor (KOR) agonists like salvinorin-A produce psychotomimetic effects through largely unknown mechanisms. In a double-blind, crossover, randomized, placebo-controlled study, acute administration of salvinorin-A increased delta and gamma brain waves while decreasing alpha waves, as measured by electroencephalography. Single-photon emission computed tomography revealed significant decreases in regional cerebral blood flow across frontal, temporal, parietal, and occipital cortices, with increases in the medial temporal lobe, amygdala, hippocampal gyrus, and cerebellum. Subjective effects resembled other psychotomimetic drugs but were distinctly dissociative, with no dysphoria reported. KOR agonism by salvinorin-A induces dramatic psychotomimetic effects alongside generalized reductions in cortical blood flow and electrical activity.

Patterns of use, desired effects, and mental health status of a sample of natural psychoactive drug users

Drugs Education Prevention and Policy May 7, 2019 Marc Aixalà, Genís Ona, Òscar Parés et al. 16 citations

A survey of 564 natural psychoactive drug (NPD) users from 52 countries found that the typical user is a well-educated adult who uses these substances sporadically. Psilocybe mushrooms (88.5%) and ayahuasca (51%) were the most used. Users reported positive life influences and good mental health. The authors argue that NPDs differ from synthetic new psychoactive substances (NPSs) in safety and use patterns, and should not be legally classified together with NPSs.

Therapeutic Potential of Natural Psychoactive Drugs for Central Nervous System Disorders: A Perspective from Polypharmacology

Current Medicinal Chemistry December 13, 2019 Genís Ona, José Carlos Bouso 15 citations

Developing highly selective drugs for central nervous system disorders has proven unsuccessful. Multi-target ligands, which act on multiple biological pathways, are now proposed as treatments offering better efficacy and safety. Natural products, including psychoactive drugs like ayahuasca and cannabis, exemplify this multi-target approach and show therapeutic promise for psychiatric and neurological conditions. This text describes how research on psychoactive drugs can be combined with polypharmacology, using ayahuasca and cannabis as examples, and discusses the advantages and disadvantages of this strategy.

Ayahuasca-induced personal death experiences: prevalence, characteristics, and impact on attitudes toward death, life, and the environment

Frontiers in Psychiatry December 19, 2023 Jonathan David, José Carlos Bouso, Maja Kohek et al. 14 citations

More than half of people who participate in ayahuasca ceremonies report having a subjective sense of death during the experience, termed Ayahuasca-induced Personal Death (APD). These experiences are typically strong and transformative, associated with an increased sense of transcending death and greater certainty that consciousness continues after death. APDs are not linked to demographics, personality, or psychopathology, but are associated with greater environmental concern, improved ability to cope with life problems, and a heightened sense of life fulfillment. The findings suggest these death experiences may be a mechanism for psychedelics' long-term positive effects.

Long-lasting analgesic effect of the psychedelic drug changa: A case report

Journal of Psychedelic Studies February 12, 2019 Genís Ona, Sebastián Troncoso 13 citations

A case report describes a long-lasting analgesic effect after use of changa, a psychedelic drug containing N,N-dimethyltryptamine and β-carboline-rich seeds of Peganum harmala. The authors suggest both pharmacological and non-pharmacological factors may be involved, but due to changa's complex actions on multiple neurotransmitter systems, further research is needed to establish specific mechanisms. This provides preliminary evidence of an analgesic effect from changa.

Polypharmacology or “Pharmacological Promiscuity” In Psychedelic Research: What Are We Missing?

ACS Chemical Neuroscience October 6, 2020 Genís Ona, Rafael G. Dos Santos, Jaime E. C. Hallak et al. 12 citations

Research on psychedelic drugs typically examines isolated compounds, but this approach may overlook important effects because these substances contain multiple active ingredients. This viewpoint argues that studying whole products like ayahuasca or Psilocybe mushrooms, rather than just single compounds, could reveal additional therapeutic or experiential properties. The authors describe how psychedelic research can incorporate a polypharmacology framework, which considers the combined actions of multiple chemicals. Ethical considerations of this broader approach are also briefly discussed.

Interactive Effects of Ayahuasca and Cannabidiol in Social Cognition in Healthy Volunteers: A Pilot, Proof-of-Concept, Feasibility, Randomized-Controlled Trial.

Journal of clinical psychopharmacology Giordano Novak Rossi, Juliana Mendes Rocha, Flávia L Osório et al. 12 citations

In a small preliminary trial, ayahuasca—with or without a 600 mg dose of cannabidiol (CBD) given 90 minutes beforehand—did not produce interactive effects on emotion recognition or empathy tasks. Both groups showed faster reaction times on these tasks and reported reduced anxiety, sedation, and discomfort, but there were no differences between the group that received CBD and the one that did not. Ayahuasca was well tolerated, causing mainly nausea and gastrointestinal discomfort, with no clinically significant changes in heart or liver measures. The safety of the combination suggests that both drugs could be tested in larger trials for anxiety disorders.

Current perspectives on psychedelic treatments in Europe.

Lancet Reg Health Eur November 20, 2025 Santiago Madero, Oscar Soto-Angona, Genís Ona et al. 9 citations

Psychedelic-assisted therapy in Europe is gaining momentum through recent initiatives in Switzerland, Germany, and the Czech Republic, though access remains limited. The authors argue for an integrative framework that considers neurobiological mechanisms, subjective experience, and contextual factors, emphasizing how effects involving neuroplasticity and critical periods may interact with psychotherapeutic processes. Context and psychological support are highlighted as crucial for shaping outcomes. Regulatory fragmentation and methodological complexities hinder progress, but publicly funded trials such as EPIsoDE and PsyPal offer promising examples of ethical and effective approaches. The future of psychedelic therapy lies in embracing its complexity.

Longitudinal and transcultural assessment of the relationship between hallucinogens, well-being, and post-traumatic growth during the COVID-19 pandemic

Scientific Reports September 11, 2023 José Carlos Bouso, Dóra Révész, Genís Ona et al. 9 citations

During the peak of the COVID-19 pandemic in April 2020, a longitudinal transcultural study surveyed English-, Spanish-, and Portuguese-speaking participants about sociodemographics, lifestyle, COVID-19 circumstances, and drug use, emphasizing hallucinogenic drugs. Users of hallucinogenic drugs reported higher psychological well-being and lower scores on psychopathology scales at baseline and follow-ups, with regular users showing even larger differences. Among those with more psychological distress, regular hallucinogen users had higher scores for post-traumatic growth. Results varied across cultural contexts, with more English-speaking regular users. The findings suggest a potential role for hallucinogens in promoting post-traumatic growth during large-scale catastrophes.

Tripping to Cope: Coping Strategies and Use of Hallucinogens during the COVID-19 Pandemic in Three Cultural Contexts

Psychoactives September 2, 2022 Genís Ona, Dóra Révész, Maja Kohek et al. 9 citations

Coping strategies are more closely linked to psychological well-being and psychopathology than to hallucinogenic drug use, according to a survey of 2,971 people from three cultural contexts followed for six months during the COVID-19 pandemic. Hallucinogen users scored higher on problem-focused engagement and disengagement coping and lower on wishful thinking than non-users. Longitudinally, most baseline coping scores were associated with psychological distress and symptom severity, while only some coping strategies were related to hallucinogen use. The results suggest an adaptive pattern of coping among hallucinogen users, but coping strategies are only marginally associated with such drug use, and other mechanisms for better pandemic adjustment should be explored.