Frontiers in Psychiatry
June 9, 2021
Simon Ruffell, Nige Netzband, WaiFung Tsang et al.
74 citations
A naturalistic study of 63 people who participated in ayahuasca ceremonies at a retreat in the Peruvian Amazon found significant improvements in depression, anxiety, and overall psychological distress, along with increased self-compassion, immediately after the retreat and sustained at six months. Depression scores on the Beck Depression Inventory dropped from 13.9 to 6.1, anxiety scores on the State-Trait Anxiety Inventory fell from 44.4 to 34.3, and scores on the Clinical Outcomes in Routine Evaluation-Outcome Measure decreased from 37.3 to 22.3. Changes in memory valence were linked to these improvements. Epigenetic results were inconclusive but suggested further research on the SIGMAR1 gene is warranted.
Psychopharmacology
July 23, 2020
Nige Netzband, Simon Ruffell, Sabriya Linton et al.
56 citations
Ayahuasca, a psychoactive brew containing DMT and MAOIs, is traditionally used ceremonially in the Amazon and increasingly by tourists seeking healing or spiritual growth. In a mixed-design study, 24 participants who ingested ayahuasca showed significant increases in agreeableness and reductions in neuroticism compared to a control group, with changes sustained at a 6-month follow-up; trait openness also increased at follow-up. Greater perceived mystical experience was linked to larger reductions in neuroticism. These results suggest a positive mediating effect of ayahuasca on personality, supporting potential therapeutic uses for serotonergic psychedelics.
PCN reports : psychiatry and clinical neurosciences
December 1, 2023
Simon G D Ruffell, Max Crosland-Wood, Rob Palmer et al.
37 citations
Ayahuasca, a psychedelic plant brew from the Amazon made from Banisteriopsis caapi vine and a DMT-containing plant like Psychotria viridis, has attracted growing interest since the year 2000. This review covers its history, pharmacology, and the phenomenological responses it produces. Anecdotal reports range from positive to accounts of physical and psychological harm. The authors discuss effects on personality and mental health, and examine phenomenological analyses of the experience. They conclude that ayahuasca is a promising psychedelic agent deserving more empirical research into its neurochemical mechanisms and potential therapeutic use.
Pharmacological research
September 1, 2024
Giorgia Caspani, Simon G D Ruffell, WaiFung Tsang et al.
13 citations
Psychedelics show promise for treating psychiatric disorders, but current explanations focus mainly on their action at serotonin receptors in the brain. This review argues that the gut microbiota, via the gut-brain axis, may also play a role. Evidence suggests psychedelics can alter gut microbiota composition, and microbial metabolism might influence psychedelic effects. The authors call for incorporating microbiome hypotheses into future research, which could lead to personalized psychedelic therapies tailored to individual gut microbiota profiles.
Drug Science Policy and Law
January 1, 2024
Simon Ruffell, Sam Gandy, WaiFung Tsang et al.
10 citations
Participating in ayahuasca retreats in a traditional Indigenous Amazonian context was associated with significant increases in nature relatedness and improvements in depression and stress, but not anxiety. A moderate negative correlation indicated that greater increases in nature relatedness were linked to lower stress levels. The study involved a mean of 6.31 ceremonies. It remains unclear whether changes resulted from the ayahuasca brew, the ceremonies, or the retreat setting. The findings suggest a potential therapeutic role for such retreats as a multidimensional intervention, but further research is needed to identify mediators and assess long-term effects.
Frontiers in Psychiatry
August 6, 2025
Grace Blest‐hopley, Giuseppe Pasculli, Simon Ruffell et al.
3 citations
Veterans with traumatic brain injuries who participated in psilocybin retreats showed improvements in PTSD, depression, and anxiety symptoms four weeks afterward. PTSD scores decreased by 50%, depression scores by 65%, and anxiety scores by 28%. Electroencephalography measurements revealed decreased delta and theta brainwave power in frontal and temporal regions, along with enhanced coherence in alpha and beta bands, suggesting improved cognitive control, emotional processing, and neural communication. The preliminary findings provide a rationale for larger controlled studies.
February 21, 2023
Simon Ruffell, Nigel Netzband, WaiFung Tsang et al.
3 citations
preprint
Ayahuasca, a psychedelic brew from the Amazon Rainforest made from the Banisteriopsis caapi vine and a DMT-containing plant like Psychotria viridis, has seen a surge in global interest since 2000. This review covers its history, pharmacology, and phenomenological effects, as well as clinical applications. Tourists increasingly travel to the Amazon to consume it, and retreat centers offering plant medicine have become a thriving business. Anecdotal reports range from evangelical accounts to stories of physical and psychological harm. The brew shows promise as a psychedelic agent warranting more empirical research into its neurochemical mechanisms and therapeutic uses.
June 24, 2022
Simon Ruffell, Sam Gandy, WaiFung Tsang et al.
2 citations
preprint
Participation in an indigenous Amazonian ayahuasca retreat, with an average of 5.85 ceremonies attended, was associated with significant increases in nature relatedness and mindfulness, as well as improvements in depression, state anxiety, and trait anxiety. Changes in nature relatedness were negatively correlated with depression, state anxiety, and trait anxiety, and positively correlated with mindfulness. It remains unclear whether these changes resulted from the brew, the ceremony, or the retreat setting. The pilot study suggests a potential therapeutic role for such retreats as a multidimensional intervention, but further research is needed to identify mediators and assess long-term effects.
Frontiers in psychiatry
January 1, 2023
Simon G D Ruffell, Nige Netzband, WaiFung Tsang et al.
1 citation
correction
This is a correction notice for a previously published article. It provides no new findings, arguments, or data.
Drug Science Policy and Law
January 1, 2023
WaiFung Tsang, Simon Ruffell, Nigel Netzband et al.
Adults who attended ayahuasca retreats in Peru reported fewer symptoms of inattention, hyperactivity, and impulsivity afterward, regardless of retreat length or number of ceremonies. In an exploratory pilot study, 49 adults completed the Adult ADHD Self-Report Scale before and after retreats lasting 8 days to 4 weeks. Scores for inattention, hyperactivity/impulsivity, and total symptoms all dropped significantly. Only four participants had a prior ADHD diagnosis. The findings suggest ayahuasca may be associated with reductions in core ADHD features, but controlled trials are needed to confirm causality.