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Jaime E. C. Hallak

Universidade de São Paulo, Clinics Hospital of Ribeirão Preto

95 papers in the library · 6,620 citations · publishing 0-2026

Papers

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Neural Network Modulation of Ayahuasca: A Systematic Review of Human Studies

Psychoactives March 20, 2023 Guilherme Henrique de Morais Santos, Lucas Silva Rodrigues, Juliana Mendes Rocha et al. 6 citations

Background: Ayahuasca is a serotoninergic hallucinogen that plays a central role in the Amazonian traditional medicine. Its psychoactive effects are associated with the presence of N,N-dimethyltryptamine (DMT), and monoamine oxidase inhibitors (MAO-A). Advances in neuroimaging investigations have provided insight into ayahuasca’s neurobiological mechanisms of action. Methods: Selecting only...

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 is one of the alkaloids naturally found in plants such as Tabernanthe iboga, which has been traditionally used by members of the Bwiti culture. Since the discovery of its anti-addictive properties by Howard S. Lotsof in 1962, ibogaine has been used experimentally to treat substance use disorders (SUD), especially those involving opioids. We aim to provide a detailed understanding of...

The effects of ketamine and classic hallucinogens on neurotrophic and inflammatory markers in unipolar treatment-resistant depression: a systematic review of clinical trials.

European Archives of Psychiatry and Clinical Neuroscience February 1, 2023 Giordano Novak Rossi, Jaime E. C. Hallak, Glen B. Baker et al. 14 citations

Although results are still preliminary, ketamine and classical hallucinogens have shown promise in recent years as novel, fast-acting antidepressants, especially for the treatment of unipolar treatment-resistant depression (TRD). Depression also seems to be related to abnormal levels of peripheral inflammatory and neurotrophic biomarkers, which may one day help to diagnose of this disorder. In...

Molecular Pathways of the Therapeutic Effects of Ayahuasca, a Botanical Psychedelic and Potential Rapid-Acting Antidepressant

Biomolecules November 2, 2022 Giordano Novak Rossi, Lorena T. L. Guerra, Glen B. Baker et al. 29 citations

Ayahuasca is a psychoactive brew traditionally used in indigenous and religious rituals and ceremonies in South America for its therapeutic, psychedelic, and entheogenic effects. It is usually prepared by lengthy boiling of the leaves of the bush Psychotria viridis and the mashed stalks of the vine Banisteriopsis caapi in water. The former contains the classical psychedelic...

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

The COVID-19 pandemic has made evident the need to develop effective strategies to cushion the psychological consequences of social catastrophes. Preliminary evidence suggests that the use of hallucinogens is a protective factor that mitigates against such stressors. However, the underlying mechanisms must be further explored. This study specifically focused on the potential role of coping...

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 is the main alkaloid of the African shrub Tabernanthe iboga. It produces hallucinogenic and psychostimulant effects, but it is currently known for the anti-addictive properties. Despite the potential therapeutic effects, several cases of fatalities and serious adverse events related to ibogaine/noribogaine use can be found in the literature. Most studies consist in case reports or were...

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

Ayahuasca is a plant decoction in traditional Amazonian medicine. Its ritual use has been internationalized, leading to policy challenges that countries should address. This study evaluates the impact of regular ayahuasca ceremony participation on health by assessing the health status of 377 participants in ayahuasca ceremonies in the Netherlands using validated health indicators. A...

Safety issues of psilocybin and LSD as potential rapid acting antidepressants and potential challenges

Expert Opinion on Drug Safety April 15, 2022 Giordano Novak Rossi, Jaime E. C. Hallak, José Carlos Bouso Saiz et al. 24 citations

There were no serious AEs related to psilocybin and LSD administration. Most AEs were expected, manageable, and transient. Nevertheless, safety and tolerability concerns regarding some effects, such as dissociation, paranoia, and confusion, remain. Thus, randomized controlled trials with bigger samples are warranted to confirm their therapeutic effects and further investigate their safety and...

Ayahuasca, a potentially rapid acting antidepressant: focus on safety and tolerability

Expert Opinion on Drug Safety March 18, 2022 Giordano Novak Rossi, Isabella Caroline Da Silva Dias, Glen B. Baker et al. 17 citations

There were no reports of serious AEs, indicating a relative safety of ayahuasca administration in controlled settings. Most common AEs included nausea, vomiting, headaches, and transient increases in cardiovascular measurements. Ayahuasca research is still in its infancy, especially concerning the absence of large and robust clinical trials to verify its antidepressant effects. Dose...

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

Abstract Objective To assess 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. Methods Post hoc analysis of endocannabinoid plasma levels (baseline, 90 and 240 min after drug intake) from two parallel‐group, randomized, placebo‐controlled...

Harmine impairs memory performance of treated rats and nontreated cagemates.

Experimental and Clinical Psychopharmacology November 4, 2021 Tânia Cristina Libânio, R. Eufrásio, Suzy S Niigaki et al. 6 citations

The interest in psychedelic substances as potential treatments for psychiatric disorders is increasing. The β-carboline harmine, an Ayahuasca component, presents hallucinogenic and antidepressant effects. Although Ayuahuasca-and consequently harmine-is usually consumed in rituals, the role of social contexts in the behavioral effects of harmine has not been investigated yet. In this sense,...

Effects of Ayahuasca on Personality: Results of Two Randomized, Placebo-Controlled Trials in Healthy Volunteers

Frontiers in Psychiatry August 6, 2021 Juliana Mendes Rocha, Giordano Novak Rossi, Flávia de Lima Osório et al. 37 citations

Rationale: Previous studies with the serotonergic hallucinogens LSD and psilocybin showed that these drugs induced changes in personality traits, such as increases in Openness. However, results are inconsistent, and the effects of ayahuasca on personality were never investigated in a controlled trial. Objectives: To assess the effects of ayahuasca on personality in two randomized,...

Ayahuasca Improves Self-perception of Speech Performance in Subjects With Social Anxiety Disorder

Journal of Clinical Psychopharmacology June 23, 2021 Rafael G. Dos Santos, Flávia de Lima Osório, Juliana Mendes Rocha et al. 85 citations

Abstract Background Ayahuasca is a classic hallucinogen with anxiolytic and antidepressive properties. Anecdotal evidence also suggests that it improves performance (eg, singing, speech). This controlled trial assessed the effects of ayahuasca on speech performance and anxiety in individuals with social anxiety disorder. Methods Seventeen volunteers with social anxiety disorder participated in...

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

Background: One of the main public health strategies adopted at the beginning of the COVID-19 pandemic consisted of implementing strict lockdowns to stop the transmission of the virus. Despite being an effective measure, the confinement and the associated social isolation create a stressful, potentially lengthy situations that has been proven to have several psychological consequences. Given...

Effects of Ayahuasca on the Recognition of Facial Expressions of Emotions in Naive Healthy Volunteers

Journal of Clinical Psychopharmacology April 13, 2021 Juliana Mendes Rocha, Giordano Novak Rossi, Flávia de Lima Osório et al. 46 citations

Abstract Background The recognition of emotions in facial expressions (REFE) is a core aspect of social cognition. Previous studies with the serotonergic hallucinogens lysergic acid diethylamide and psilocybin showed that these drugs reduced the recognition of negative (fear) faces in healthy volunteers. This trial assessed the acute and prolonged effects of a single dose of ayahuasca on the...

The Use of Classic Hallucinogens/Psychedelics in a Therapeutic Context: Healthcare Policy Opportunities and Challenges

Risk Management and Healthcare Policy March 1, 2021 Rafael G. Dos Santos, José Carlos Bouso, Juliana Mendes Rocha et al. 58 citations

Psychedelics or serotonergic hallucinogens are a group of substances that share the agonism of serotonergic 5-HT2A receptors as their main mechanism of action. Its main effects include changes in perception, cognitive process, and mood. Despite being used for centuries by different cultures in ritual contexts, these substances have currently aroused the interest of science and industry for...

Nitrous oxide as an adjunctive therapy in major depressive disorder: a randomized controlled double-blind pilot trial

Brazilian Journal of Psychiatry February 18, 2021 Mara C. Guimarães, Tiago M. Guimarães, Jaime E. C. Hallak et al. 41 citations

OBJECTIVE: Major depressive disorder (MDD) is related to glutamatergic dysfunction. Antagonists of glutamatergic N-methyl-D-aspartate receptor (NMDAR), such as ketamine, have antidepressant properties. Nitrous oxide (N2O) is also a NMDAR antagonist. Thus, this study aimed to evaluate the effects of augmenting antidepressant treatment with N2O. METHODS: This double blind, placebo-controlled...

Rapid and sustained decreases in suicidality following a single dose of ayahuasca among individuals with recurrent major depressive disorder: results from an open-label trial.

Psychopharmacology February 1, 2021 Richard J. Zeifman, Nikhita Singhal, Rafael G. Dos Santos et al. 79 citations

Suicidality is a major public health concern with limited treatment options. Accordingly, there is a need for innovative interventions for suicidality. Preliminary evidence indicates that treatment with the psychedelic ayahuasca may lead to decreases in depressive symptoms among individuals with major depressive disorder (MDD). However, there remains limited understanding of whether ayahuasca...

Psychedelic Medicines in Major Depression: Progress and Future Challenges.

Advances in experimental medicine and biology 2021 José Carlos Bouso, Genís Ona, Rafael G. Dos Santos et al. 6 citations

The volume of research on the therapeutic use of psychedelic drugs has been increasing during the last decades. Partly because of the need of innovative treatments in psychiatry, several studies have assessed the safety and efficacy of drugs like psilocybin or ayahuasca for a wide range of mental disorders, including major depression. The first section of this chapter will offer an introduction...

Neuropharmacological Effects of the Main Phytocannabinoids: A Narrative Review.

Advances in experimental medicine and biology 2021 Rafael G. Dos Santos, Jaime E. C. Hallak, José Alexandre S. Crippa

Cannabis can synthetize more than 400 compounds, including terpenes, flavonoids, and more than 100 phytocannabinoids. The main phytocannabinoids are Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis-based products are used as medicines in several countries. In this text, we present an overview of the main neurochemical mechanisms of action of the phytocannabinoids, especially THC...

Essential oil-based dispersive liquid-liquid microextraction for the determination of N,N-dimethyltryptamine and β-carbolines in human plasma: A novel solvent-free alternative

Talanta December 9, 2020 Gabriela de Oliveira Silveira, Felipe Rebello Lourenço, Ana Miguel Fonseca Pego et al. 15 citations

The present study describes the development of a novel solvent-free vortex-assisted dispersive liquid-liquid microextraction alternative based on a natural essential oil as extracting solvent (VA-EO-DLLME) for the determination of N,N-dimethyltryptamine (DMT), harmine (HRM), harmaline (HRL) and tetrahydroarmine (THH) (compounds found in the ayahuasca tea, a psychedelic plant preparation) in...

Risk assessment of ayahuasca use in a religious context: self-reported risk factors and adverse effects

Brazilian Journal of Psychiatry October 30, 2020 Ícaro Durante, Rafael G. Dos Santos, José Carlos Bouso et al. 49 citations

A minority of participants reported being very negatively affected by persistent adverse effects. Psychiatric medication use while participating in ayahuasca rituals was not associated with increased adverse effects. For the most part, the institution's practices seem sufficient to prevent exacerbated reactions. Future studies may focus on negatively affected users.

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 with psychedelic drugs has mainly focused on isolated compounds. However, this approach is challenged by the "polypharmacology" paradigm. In this Viewpoint, we suggest that we may be missing something if we do not use the whole product in the case of ayahuasca or Psilocybe mushrooms. After describing how research on psychedelic drugs can be effectively combined with the...