Psychological Medicine
June 15, 2018
Fernanda Palhano-Fontes, Dayanna Barreto, Heloisa Onias et al.
827 citations
A single dose of ayahuasca reduced depression severity more than placebo in patients with treatment-resistant depression. Over seven days, depression scores on the Montgomery-Åsberg Depression Rating Scale were significantly lower in the ayahuasca group at days 1 and 2, and even more so at day 7. Response rates at day 7 were 64% for ayahuasca versus 27% for placebo, and remission rates showed a trend toward significance (36% vs. 7%). Effect sizes grew from day 1 to day 7, indicating sustained improvement. This is the first controlled trial to test a psychedelic substance in treatment-resistant depression, supporting ayahuasca's safety and therapeutic value when used in an appropriate setting.
Journal of Clinical Psychopharmacology
June 23, 2021
Rafael G. Dos Santos, Flávia de Lima Osório, Juliana Mendes Rocha et al.
85 citations
Ayahuasca, a classic hallucinogen with anxiolytic and antidepressive properties, improved self-perception of speech performance in individuals with social anxiety disorder. In a pilot, proof-of-concept, randomized, parallel-group trial with 17 volunteers, ayahuasca significantly increased positive self-statements during a public-speaking test compared with placebo, alongside increased somatic symptoms such as nausea and gastrointestinal discomfort. The drug did not significantly alter task-related anxiety or recognition of emotions in facial expressions, suggesting a specific cognitive effect on speech performance. Ayahuasca was well tolerated overall, and further research is needed to understand the mechanisms involved.
Journal of Clinical Psychopharmacology
April 13, 2021
Juliana Mendes Rocha, Giordano Novak Rossi, Flávia de Lima Osório et al.
46 citations
A single dose of ayahuasca did not alter the recognition of emotions in facial expressions compared with placebo in healthy volunteers. The drug was well tolerated, producing nausea, gastrointestinal discomfort, and vomiting, with some reports of visual effects, tranquility, and well-being, and few reports of transient anxiety or confusion. No significant effects appeared on cardiovascular measures or brain-derived neurotrophic factor levels. A significant time-dependent deterioration of alkaloids, especially dimethyltryptamine, was observed. The absence of effects on emotion recognition may stem from the dose used, alkaloid degradation, learning effects, or the sample's high educational level.
Frontiers in Psychiatry
August 6, 2021
Juliana Mendes Rocha, Giordano Novak Rossi, Flávia de Lima Osório et al.
37 citations
In two small randomized placebo-controlled trials, ayahuasca did not consistently change personality traits. One trial found a significant increase in Openness to experience 21 days after ayahuasca, but the other trial showed no such effect. Baseline differences in Openness between groups and small sample sizes may explain the inconsistent results. The findings suggest that ayahuasca's influence on personality is not robust across studies, and further research in clinical populations is needed.
Molecules
April 29, 2020
Gabriela de Oliveira Silveira, Rafael G. Dos Santos, Felipe Rebello Lourenço et al.
36 citations
Ayahuasca tea, a hallucinogenic beverage used in religious and therapeutic contexts, was tested for the stability of its main alkaloids—DMT, harmine, tetrahydroharmine, and harmaline—under three storage conditions: one year in a refrigerator (plastic or glass containers), seven days at 37°C (simulating mail transport), and three freeze-thaw cycles. DMT showed no significant degradation in any condition. However, harmala alkaloids exhibited substantial variation, including degradation and concentration increases, likely due to inter-conversion and leaching from tea precipitate. Thus, quantifying alkaloids before administration in controlled studies is essential.
Behavioural Brain Research
August 23, 2021
Carolina Aparecida Faria Almeida, Antônio Alves Pereira-Júnior, Jéssica Gonçalves Rangel et al.
33 citations
Repeated ethanol administration to mice produced behavioral sensitization, a model of alcohol use disorder. Subsequent daily treatment with ayahuasca (1.76 mg/kg DMT) for eight days attenuated that sensitization. Ayahuasca also reduced the anxiety-like behavior triggered by ethanol withdrawal and prevented ethanol-induced changes in 5-HT1a receptor and prodynorphin levels in the hippocampus, while reducing ethanol's effects on the dynorphin/prodynorphin ratio in the striatum. The results suggest ayahuasca may modulate neuroplastic changes caused by ethanol.
bioRxiv (Cold Spring Harbor Laboratory)
January 27, 2017
Fernanda Palhano-Fontes, Dayanna Barreto, Heloisa Onias et al.
22 citations
preprint
A single dose of ayahuasca produced significant antidepressant effects in patients with treatment-resistant depression compared to placebo. Depression severity, measured by the Montgomery–Åsberg Depression Rating Scale (MADRS), was significantly lower in the ayahuasca group at one, two, and seven days after dosing. Effect sizes increased over time, reaching a Cohen's d of 1.49 at day seven. Response rates were significantly higher in the ayahuasca group at day seven (64% vs. 27%), and remission rates were marginally significant (36% vs. 7%). This controlled trial supports the safety and therapeutic value of ayahuasca in treating depression.
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.
Talanta
December 9, 2020
Gabriela de Oliveira Silveira, Felipe Rebello Lourenço, Ana Miguel Fonseca Pego et al.
15 citations
A new sample-preparation method uses eucalyptus essential oil, instead of conventional organic solvents, to extract four ayahuasca-related compounds (DMT, harmine, harmaline, and tetrahydroharmine) from human plasma. After optimizing the procedure with factorial experiments, the method was validated and applied to 13 real plasma samples. Detection limits were ≤1.0 ng/mL, and the method was linear up to 150 ng/mL. Recovery averaged 50%, and matrix effects showed ion suppression of 56–83%. The approach is simple, fast, and environmentally friendly, offering a green alternative for forensic and clinical drug analysis.
Journal of Psychoactive Drugs
December 22, 2018
Sueli Moreira Mello, Paula Christiane Soubhia, Gabriela de Oliveira Silveira et al.
15 citations
Ayahuasca, a beverage made from Banisteriopsis caapi and Psychotria viridis, contains monoamine oxidase inhibitors and N,N-dimethyltryptamine, which produces visionary effects. Despite concerns about liver injury from oral consumption, this study measured biochemical markers of liver damage in 22 volunteers who had consumed ayahuasca at least twice monthly for over a year. No significant changes were found in alanine aminotransferase, aspartate aminotransferase, bilirubin, creatinine, urea, lactate dehydrogenase, alkaline phosphatase, or gamma glutamyl transferase. Chronic ayahuasca use in a religious setting apparently does not impair hepatic function.
Frontiers in chemistry
January 1, 2020
Gabriela de Oliveira Silveira, Felipe Rebello Lourenço, Vitor Bruno et al.
12 citations
A greener, faster method using hollow fiber liquid-phase microextraction (HF-LPME) and LC-MS/MS was developed to measure DMT and three harmala alkaloids in human urine. The method avoids large amounts of toxic solvents. It detects DMT at 1.0 ng/ml and harmala alkaloids at 2.0 ng/ml, with a quantifiable range of 5-200 ng/ml. Precision, accuracy, and recovery (above 80%) met acceptance criteria. Analysis of urine from four subjects confirmed the method's feasibility. The approach offers a simple, time-saving alternative for studying ayahuasca components in biological samples.
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.
Journal of Psychedelic Studies
March 1, 2019
Giordano Novak Rossi, Eduardo José Crevelin, Gabriela de Oliveira Silveira et al.
10 citations
All five organic solvents tested—n-hexane, ethyl acetate, n-butanol, dichloromethane, and chloroform—successfully extracted non-purified N,N-dimethyltryptamine (DMT) from Mimosa hostilis roots using a common Internet-based extraction method. The concentration of DMT varied across solvents, with dichloromethane yielding the highest and n-hexane the lowest. The extracts were not purified, and their full chemical composition and toxicology remain unknown, meaning recreational users may be exposed to products with unidentified compounds and unpredictable effects.
November 6, 2020
Gabriela de Oliveira Silveira
Ayahuasca is an indigenous beverage with psychedelic properties. The text provides only a fragment describing the drink's origin and psychoactive nature, without any further details on methods, findings, or arguments.