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Paulo César Ribeiro Barbosa

14 papers in the library · 1,216 citations · publishing 2005-2026

Papers

Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study

PLoS ONE August 8, 2012 José Carlos Bouso, Débora González, Sabela Fondevila et al. 313 citations

Regular ayahuasca use over one year is associated with better psychological well-being, mental health, and cognitive performance compared to active controls in non-ayahuasca religions. Users scored higher on Reward Dependence and Self-Transcendence, lower on Harm Avoidance and Self-Directedness, and showed significantly lower psychopathology scores. They performed better on tests of attention, executive function, and working memory (Stroop test, Wisconsin Card Sorting Test, Letter-Number Sequencing). Life attitude measures indicated greater spiritual orientation, purpose in life, and psychosocial well-being. No evidence of psychological maladjustment, mental health deterioration, or cognitive impairment emerged in the ayahuasca group.

Assessment of addiction severity among ritual users of ayahuasca

Drug and Alcohol Dependence June 17, 2010 Josep María Fábregas, Débora González, Sabela Fondevila et al. 228 citations

Regular ritual use of ayahuasca, a psychoactive Amazonian tea containing N,N-dimethyltryptamine, does not appear to cause the psychosocial problems typical of other drugs of abuse. In two studies comparing ayahuasca users (56 jungle-based and 71 urban-based) with matched controls, users scored significantly lower on the Addiction Severity Index (ASI) Alcohol Use and Psychiatric Status subscales. Jungle-based users had a higher frequency of past illicit drug use, but this had ceased at examination except for cannabis. At one-year follow-up, abstinence from illicit drugs was maintained except for cannabis in the jungle group. ASI differences remained significant for the jungle group but not the urban group. A time-dependent worsening was observed only in the Family/Social relationships subscale in the urban group.

Altered States of Consciousness and Short-Term Psychological After-Effects Induced by the First Time Ritual Use of Ayahuasca in an Urban Context in Brazil

Journal of Psychoactive Drugs June 1, 2005 Paulo César Ribeiro Barbosa, Joel Sales Giglio, Paulo Dalgalarrondo 121 citations

After first-time ritual use of ayahuasca in the Santo Daime and União do Vegetal religious groups, participants reported predominantly positive expectations beforehand. The most salient altered-state experiences included visual phenomena, a sense of the numinous, peacefulness, insights, and some distressing reactions. In the Santo Daime group, minor psychiatric symptoms significantly reduced. Both groups reported behavioral changes toward assertiveness, serenity, and vivacity or joy. Findings are discussed in terms of set and setting, suggestibility, and ayahuasca's unique effects.

A six-month prospective evaluation of personality traits, psychiatric symptoms and quality of life in ayahuasca-naïve subjects.

Journal of psychoactive drugs September 1, 2009 Paulo César Ribeiro Barbosa, Irene Maurício Cazorla, Joel Sales Giglio et al. 113 citations

Twenty-three people were assessed just before and six months after their first ayahuasca experience in two Brazilian religious groups. In the Santo Daime group, minor psychiatric symptoms decreased, mental health improved, and attitudes shifted toward greater confidence and optimism. In the União do Vegetal group, physical pain decreased and attitudes shifted toward greater independence. More frequent ayahuasca use was linked to more independence, while a longer period without ayahuasca was linked to less independence. The authors discuss possible mechanisms behind these changes and suggest areas for future research.

Health status of ayahuasca users.

Drug testing and analysis January 1, 2012 Paulo César Ribeiro Barbosa, Suely Mizumoto, Michael P Bogenschutz et al. 112 citations

Ayahuasca, a psychedelic brew traditionally used by Amazonian peoples, has spread to urban areas worldwide, raising concerns about potential health risks. A review of 15 studies from the PubMed database examined the emotional, cognitive, and physical health effects of ayahuasca use after acute effects subsided. The accumulated data suggest that ayahuasca use is safe and may even be beneficial under certain conditions. However, methodological bias in the reviewed studies may have contributed to the preponderance of beneficial effects and the few adverse effects reported. The data do not yet allow definitive conclusions about ayahuasca's effects on mental and physical health, but some studies point toward beneficial outcomes.

Psychological and neuropsychological assessment of regular hoasca users.

Comprehensive psychiatry November 1, 2016 Paulo César Ribeiro Barbosa, Rick J Strassman, Dartiu Xavier Da Silveira et al. 104 citations

Regular ritual use of hoasca (ayahuasca) within a Brazilian religious group in the United States is associated with lower depression and confusion, higher agreeableness and openness, better memory performance, and less recent alcohol use compared to matched controls. The study of 30 members of the União do Vegetal and 27 non-user controls found no adverse effects on neuropsychological function. Lifetime hoasca use correlated with fewer physical health role limitations and less heavy alcohol use, suggesting the religious use of this psychedelic brew may have positive effects on mood and substance use.

Assessment of Alcohol and Tobacco Use Disorders Among Religious Users of Ayahuasca

Frontiers in Psychiatry April 24, 2018 Paulo César Ribeiro Barbosa, Luís Fernando Tófoli, Michael P. Bogenschutz et al. 95 citations

Members of the Brazilian União do Vegetal (UDV) who drink ayahuasca in ceremonies show lower rates of current alcohol and tobacco use disorders compared to the general Brazilian population, even though their lifetime use of these substances is higher. Among 1,947 UDV members aged 18 and older, those who attended more ceremonies in the previous year and had longer membership reported greater reductions in alcohol and tobacco problems. The findings suggest that regular ceremonial ayahuasca use, within a religious context, is associated with reduced substance misuse, particularly for adults over 24 years old.

Ayahuasca and Its DMT- and β-carbolines – Containing Ingredients Block the Expression of Ethanol-Induced Conditioned Place Preference in Mice: Role of the Treatment Environment

Frontiers in Pharmacology May 29, 2018 Elisangela Gouveia Cata-Preta, Yasmim A. Serra, Eliseu Da Cruz Moreira-Junior et al. 50 citations

Ayahuasca, a hallucinogenic beverage containing DMT and β-carbolines, can reduce ethanol reward in male mice without itself being rewarding at certain doses. An intermediate dose of ayahuasca induced conditioned place preference (CPP), while higher doses and its plant components Banisteriopsis caapi (Bc) and Psychotria viridis (Pv) did not. Pretreatment with ayahuasca blocked the development of ethanol-induced CPP, whereas Bc and Pv alone had no effect. Post-conditioning treatment with ayahuasca, Bc, or Pv in the ethanol-paired environment blocked expression of ethanol-induced CPP; treatment in the saline-paired compartment also blocked expression for intermediate ayahuasca and Bc doses, and for Pv. The environment influences these therapeutic effects.

Role of 5-HT2A receptors in the effects of ayahuasca on ethanol self-administration using a two-bottle choice paradigm in male mice

Psychopharmacology March 7, 2022 Yasmim A. Serra, Thaísa Barros-Santos, Alexia Anjos-Santos et al. 28 citations

In mice undergoing alcohol abstinence, treatment with ayahuasca blocked the return of alcohol self-administration. The effects depended on activation of the 5-HT2A receptor. The findings suggest that ayahuasca and other 5-HT2A receptor agonists could serve as adjunctive pharmacotherapies for alcohol use disorder.

Ayahuasca blocks the reinstatement of methylphenidate-induced conditioned place preference in mice: behavioral and brain Fos expression evaluations

Psychopharmacology July 16, 2020 Henrique Sousa Reis, Isa R. S. Rodrigues, Alexia Anjos-Santos et al. 21 citations

Ayahuasca, a hallucinogenic beverage used in traditional Amazonian rituals, blocked the reinstatement of methylphenidate-induced conditioned place preference in mice, indicating reduced drug-seeking behavior. Both ayahuasca (100 mg/kg, orally) and methylphenidate (10 mg/kg, i.p.) separately induced conditioned place preference. However, methylphenidate altered Fos expression in several limbic brain regions associated with drug abuse, while ayahuasca had limited effects on Fos expression. Treatment with ayahuasca after conditioning with methylphenidate prevented reinstatement of the conditioned place preference and generally blocked the changes in Fos expression induced by methylphenidate conditioning or reexposure. These findings suggest ayahuasca restored normal brain function in areas linked to long-term drug wanting or seeking.

Psychosocial and Drug Use Assessment of Regular vs. Non-Regular Ayahuasca Users in a Brazilian Sample: a Web-Based Survey

Substance Use & Misuse April 25, 2022 Dimitri Daldegan‐bueno, Dóra Révész, Paulo Rogério Morais et al. 15 citations

Regular ceremonial use of ayahuasca is associated with lower anxiety, less negative affect, higher intrinsic religiosity, and reduced past-month use of both licit and illicit substances compared to non-regular use. Regular users also reported lower general and physical quality of life. The study compared 101 regular users with 185 non-regular users in Brazil, finding no differences in lifetime drug use between groups after adjusting for sociodemographic factors.

Hallucinogen Rating Scale (HRS) - Versão brasileira: tradução e adaptação transcultural

Archives of Clinical Psychiatry (São Paulo) January 1, 2011 Suely Mizumoto, Dartiu Xavier Da Silveira, Paulo César Ribeiro Barbosa et al. 14 citations

A Brazilian Portuguese version of the Hallucinogen Rating Scale (HRS) has been produced through translation, back-translation, and committee review, following guidelines for semantic and conceptual equivalence. The HRS is a standard questionnaire used in the U.S. and Europe to evaluate subjective effects of hallucinogens, including ayahuasca. The final version is intended to provide a sensitive instrument for quantifying hallucinogen-induced states in Brazil, where scientific interest in such substances is growing.

Santo Daime in the context of the new religious consciousness

April 8, 2016 Beatriz Caiuby Labate, Rafael Guimarães Dos Santos, Brian Anderson et al. 2 citations

Ayahuasca, used ritually in South American religions such as Santo Daime and União do Vegetal and in Amazonian rehabilitation centers, shows therapeutic potential for treating substance dependence. Anthropological and psychiatric data indicate that ritual ayahuasca use can aid healing from addiction. The chapter reviews evidence from these settings and discusses methodological, ethical, and political considerations for future research. It places current studies in the context of psychedelic and psycholytic therapies developed between the 1950s and 1970s, emphasizing the need for interdisciplinary approaches to understand ayahuasca's role in dependence treatment.

Ayahuasca use and improvements in suicidal behavior: An exploratory qualitative study

Psychedelics May 16, 2026 Nádia Valéria Moreira Santos, Cristiane Ferreira Silveira, Camila Gutieres Dos Santos Soares Costa et al.

Interviews with nine Brazilian participants who took ayahuasca in neoshamanic ceremonies suggested that the experience helped reduce suicidal thoughts and behaviors. Three themes emerged: motivations for seeking ayahuasca, strategies for strengthening psychological well-being afterward, and the perceived health benefits of the psychedelic experience itself. The ceremonial use of ayahuasca may offer a promising model of care, especially in communities with limited access to advanced medical treatment.