Understanding variations in knowledge and attitudes of psychiatrists to psilocybin therapy is important for the collective discourse about the potential impact on clinical practice and public health in Ireland.

A 28-item questionnaire was designed based on previous studies and distributed to psychiatrists in Ireland via online mailing lists and at in-person academic events.

151 psychiatrists completed the questionnaire (73.3% were under 40 years of age, 76.0% were trainees, and 49.0% were female). In the total sample, 81.5% agreed that psilocybin therapy shows promise in the treatment of psychiatric disorders and 86.8% supported funding research, 86.8% would be willing to refer a patient if it was licensed and indicated, and 78.1% would consider the treatment for themselves, if indicated. Conversely, 6.6% agreed that psilocybin therapy was unsafe even under medical supervision, and 21.9% thought it was potentially addictive. 15.9% of the total sample reported at least one concern including, lack of robust evidence, long-term effectiveness, superiority to current interventions, potential harmful effects, cost and accessibility, and impartiality. Less than half of respondents felt knowledgeable (40.0%) and 9.9% felt adequately prepared to participate in psilocybin therapy. Consultant psychiatrists trended towards less optimism for a potential role in bipolar depression and emotionally unstable personality disorder compared to trainee psychiatrists.

Overall psychiatrists in Ireland held positive attitudes towards psilocybin therapy. However, there was a lack of knowledge evident. Addressing the knowledge gap and aligning with the best available evidence will be key if psychedelic therapy is to prevail in a clinical setting.

Access to psychedelic drugs is liberalizing, yet responses are highly unpredictable. It is therefore imperative that we improve our ability to predict the nature of the acute psychedelic experience to improve safety and optimize potential therapeutic outcomes. This study sought to validate the ‘Imperial Psychedelic Predictor Scale’ (IPPS), a short, widely applicable, prospective measure intended to be predictive of salient dimensions of the psychedelic experience.

Using four independent datasets in which the IPPS was completed prospectively – two online surveys of ‘naturalistic’ use (N = 741, N = 836) and two controlled administration datasets (N = 30, N = 28) – we conducted factor analysis, regression, and correlation analyses to assess the construct, predictive, and convergent validity of the IPPS.

Our approach produced a 9-item scale with good internal consistency (Cronbach's α = 0.8) containing three factors: set, rapport, and intention. The IPPS was significantly predictive of ‘mystical’, ‘challenging’, and ‘emotional breakthrough’ experiences. In a controlled administration dataset (N = 28), multiple regression found set and rapport explaining 40% of variance in mystical experience, and simple regression found set explained 16% of variance in challenging experience. In another (N = 30), rapport was related to emotional breakthrough explaining 9% of variance.

Together, these data suggest that the IPPS is predictive of relevant acute features of the psychedelic experience in a broad range of contexts. We hope that this brief 9-item scale will be widely adopted for improved knowledge of psychedelic preparedness in controlled settings and beyond.

Anxiety disorders are a major public health burden with limited treatment options.

We investigated the long-term safety and efficacy of lysergic acid diethylamide (LSD)-assisted therapy in patients with anxiety with or without life-threatening illness.

This study was an a priori-planned long-term follow-up of an investigator-initiated, two-centre trial that used a double-blind, placebo-controlled, two-period, random-order, crossover design with two sessions with either oral LSD (200 μg) or placebo per period. Participants (n = 39) were followed up 1 year after the end-of-study visit to assess symptoms of anxiety, depression and long-term effects of psychedelics using Spielberger's State-Trait Anxiety Inventory–Global (STAI-G), the Beck Depression Inventory (BDI), the Persisting Effects Questionnaire and measures of personality traits using the NEO-Five-Factor Inventory.

Participants reported a sustained reduction of STAI-G scores compared with baseline (least square means (95% CI) = −21.6 (−32.7, −10.4), d = 1.04, P < 0.001, for those who received LSD in the first period (94 weeks after the last LSD treatment) and −16.5 (−26.2, −6.8), d = 1.02, P < 0.05, for those who received LSD in the second period (68 weeks after the last LSD treatment)). Similar effects were observed for comorbid depression with change from baseline BDI scores of −8.1 (−13.2, −3.1), d = 0.71, P < 0.01, and −8.9 (−12.9, −4.9), d = 1.21, P < 0.01, for the LSD-first and placebo-first groups, respectively. Personality trait neuroticism decreased (P < 0.0001) and trait extraversion increased (P < 0.01) compared with study inclusion. Individuals attributed positive long-term effects to the psychedelic experience.

Patients reported sustained long-term effects of LSD-assisted therapy for anxiety.

Monoamine neurotransmitters play a role in aggression, especially when altered by illicit substances. However, some literature suggests that not all illicit substances may lead to aggression, notably psychedelics. This narrative review investigates the associations between serotonergic psychedelics and MDMA on aggressive behaviour.

PubMed and PsycINFO were searched for original, peer-reviewed articles evaluating the effects of serotonergic psychedelics and 3,4-methyl enedioxy methamphetamine (MDMA) on violent and aggressive behaviour using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

After removing duplicates, a total of 555 articles were screened, with 16 meeting the inclusion criteria. One additional article was obtained through reference screening bringing the total to 17 articles. Of these 17 articles, 14 studies focused on MDMA and three on serotonergic psychedelics. Findings were mixed, with some results demonstrating increased aggression following psychedelics and others suggesting protective effects. Limitations in the current literature include varied definitions of psychedelics, lack of standardised objective outcome measures and failure to control for confounding.

As psychedelic research continues to expand, further assessment on the effects of serotonergic psychedelics and MDMA on aggressive behaviour is required.

Previous research has proposed that there may be potential synergies between psychedelic and meditation interventions, but there are still knowledge gaps that merit further investigation.

Using a longitudinal observational research design with samples representative of the US and UK adult population with regard to sex, age, and ethnicity (N = 9732), we investigated potential associations between self-reported psychedelic use and meditation practice.

The follow-up survey was completed by 7667 respondents (79% retention rate), with 100 respondents reporting psychedelic use during the 2-month study period (1.3% of follow-up respondents). In covariate-adjusted regression models, psychedelic use during the study period was associated with greater increases in the number of days of mindfulness meditation practice in the past week (B = 0.40, p = 0.004). Among those who reported psychedelic use during the study period, covariate-adjusted regression models revealed that the subjective experience of insight during respondents' most intense psychedelic experience in that period was also associated with greater increases in the number of days of mindfulness and loving-kindness or compassion meditation practice in the past week (B = 0.42, p = 0.021; B = 0.38, p = 0.017). Notably, more days of loving-kindness or compassion meditation practice in the past week at baseline was associated with less severe subjective feelings of death or dying during respondents' most intense psychedelic experience in the study period (B = −0.29, p = 0.037).

Psychedelic use might lead to greater engagement with meditation practices such as mindfulness meditation, while meditation practices such as loving-kindness or compassion medication might buffer against certain challenging experiences associated with psychedelic use.

People with terminal illnesses often experience psychological distress and associated disability. Recent clinical trial evidence has stimulated interest in the therapeutic use of psychedelics at end of life. Much uncertainty remains, however, mainly due to methodological difficulties that beset existing trials. We conducted a scoping review of pipeline clinical trials of psychedelic treatment for depression, anxiety, and existential distress at end of life.

Proposed, registered, and ongoing trials were identified from 2 electronic databases (ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform). Recent reviews and both commercial and non-profit organization websites were used to identify additional unregistered trials.

In total, 25 studies were eligible, including 13 randomized controlled trials and 12 open-label trials. Three trials made attempts beyond randomization to assess expectancy and blinding effectiveness. Investigational drugs included ketamine (n = 11), psilocybin (n = 10), 3,4-methylenedioxymethamphetamine (n = 2), and lysergic acid diethylamide (n = 2). Three trials involved microdosing, and fifteen trials incorporated psychotherapy.

A variety of onging or upcoming clinical trials are expected to usefully extend evidence regarding psychedelic-assisted group therapy and microdosing in the end-of-life setting. Still needed are head-to-head comparisons of different psychedelics to identify those best suited to specific indications and clinical populations. More extensive and rigorous studies are also necessary to better control expectancy, confirm therapeutic findings and establish safety data to guide the clinical application of these novel therapies.

The non-selective serotonin 2A (5-HT2A) receptor agonist lysergic acid diethylamide (LSD) holds promise as a treatment for some psychiatric disorders. Psychedelic drugs such as LSD have been suggested to have therapeutic actions through their effects on learning. The behavioural effects of LSD in humans, however, remain incompletely understood. Here we examined how LSD affects probabilistic reversal learning (PRL) in healthy humans.

Healthy volunteers received intravenous LSD (75 μg in 10 mL saline) or placebo (10 mL saline) in a within-subjects design and completed a PRL task. Participants had to learn through trial and error which of three stimuli was rewarded most of the time, and these contingencies switched in a reversal phase. Computational models of reinforcement learning (RL) were fitted to the behavioural data to assess how LSD affected the updating (‘learning rates’) and deployment of value representations (‘reinforcement sensitivity’) during choice, as well as ‘stimulus stickiness’ (choice repetition irrespective of reinforcement history).

Raw data measures assessing sensitivity to immediate feedback (‘win-stay’ and ‘lose-shift’ probabilities) were unaffected, whereas LSD increased the impact of the strength of initial learning on perseveration. Computational modelling revealed that the most pronounced effect of LSD was the enhancement of the reward learning rate. The punishment learning rate was also elevated. Stimulus stickiness was decreased by LSD, reflecting heightened exploration. Reinforcement sensitivity differed by phase.

Increased RL rates suggest LSD induced a state of heightened plasticity. These results indicate a potential mechanism through which revision of maladaptive associations could occur in the clinical application of LSD.

A resurgence of research investigating the administration of psychedelic compounds alongside psychotherapy suggests that this treatment is a promising intervention for anxiety, depression, and existential distress in people with cancer. However, psychedelic treatment that induces a mind-altering experience potentially poses barriers to vulnerable cancer patients, and health-care practitioners may have concerns about referring their patients to trials investigating this approach. The aim of the current study was to investigate the perceptions of cancer health-care practitioners based in New Zealand and the USA related to psychedelic-assisted therapy.

This study utilized a cross-sectional survey of cancer health-care practitioners in New Zealand and the USA via convenience sampling to identify their perceptions about the concept of conducting psychedelic-assisted therapy with cancer patients.

Participants perceived that (1) psychedelic-assisted therapy has the potential to provide benefit for cancer patients, (2) research in this area across a variety of domains is important, (3) work should consider spiritual and indigenous perspectives of health, and (4) there was willingness to refer patients to trials in this area, especially patients with advanced disease who were no longer going through curative treatment. Participants in the USA had greater awareness of psychedelics than the New Zealand sample; however, New Zealand participants more strongly believed that spiritual/indigenous factors should be considered in psychedelic-assisted therapy.

Cancer health-care practitioners in our sample considered research investigating the potential for psychedelic-assisted therapies to be important and may be more open to studies that start in palliative and end-of-life contexts.

Lysergic acid diethylamide (LSD) a semi synthetic hallucinogen, was first synthetized by Albert Hofmann in 1938 and its psychological properties were not discovered until 1943. There was a brief renaissance of its use in psychiatry, specifically in assisted psychotherapy for the treatment of alcoholism, neurosis and psychosomatic disorders. However, research with LSD and others psychedelics substances rapidly came to an end with its broad international prohibition in the 1970´s.

This work aims to provide an understanding on the potential benefits of LSD in mental disorders, as well as its mechanism of action and effects on human brain.

A non-systematic review was performed on PubMed database, using the key words “LSD, mental disorder, neuroimaging, cerebral plasticity, psychedelics, substance use disorder”. Websites of the Berkley Foundation and Multidisciplinary Association For Psychedelic Studies (MAPS) were also searched.

Significant evidence has emerged that LSD may have a role in the treatment for some mental disorder, including drug and alcohol dependence and anxiety associated with life threatening diseases. Evidence based on modern neuroimaging technique suggest that LSD alters the brain blood flow, electrical activity, and network communication patterns. Preclinical evidence also demonstrated that psychedelics affect neuroplasticity after acute and chronic administration.

Based on the available evidence LSD when administered safely in a methodologically supervised psychotherapeutic setting can have a potential use for certain psychiatric conditions, suggesting that larger controlled studies are warranted

No significant relationships.

After a long moratorium since the Controlled Substances Act was passed in 1970, there has been a resurgence of research on the potential therapeutic benefits of psychedelic (PE) compounds. It has been widely believed that the PE effect is a result of the interaction between the drug and the mindset of the patient (the “set”) with the external physical and social conditions (the “setting”). In order to control non-pharmacological variables and improve therapeutic outcome two types of psychological approaches to PE use have emerged traditionally. One is based on psychoanalytically informed talk therapy with low to moderate doses of a PE agent with the goal of facilitating a discharge of emotionally charged mental contents (psycholytic therapy). The other used one or several high doses of a PE to create an “overwhelming experience,” which was then followed up in integrative sessions (psychedelic therapy).

Currently, it is unclear which one is better than another, these two methods are frequently mixed, and all-together carry the name of psychedelic-assisted psychotherapy. There has also been some discrepancy about what is the right “set” and “setting”.

To add some anchor points for (and at the same time warn about the limitations of) the reemerging field of psychedelic-assisted psychotherapy the authors refer to anthropological observations in cultures, where PE use has a long practice historically.

As part of healing ceremonials PE has usually been administered in a tight community with shared cosmology (“set”) and ritual context (“setting”).

These are difficult-to-reach conditions for someone coming from Western tradition.

No significant relationships.

Ayahuasca is an hallucinogenic tea prepared from the Amazonian vine Banisteriopsis caapi and the leaves of the plant Psychotria Viridis. Banisteriopsis caapi contains monoamine oxidase inhibitors (MAO) that render the N, N-dimethyltryptamine (DMT) of Psychotria Viridis active. This brew is being used as a sacrament in syncretic religions in urban areas of Brazil and worldwide with the purpose of enabling a spiritual experience as well as healing for a variety of conditions such as drug addiction, depression and anxiety disorders.

This work aims to provide an understanding on the potential benefits of ayahuasca in psychiatric symptoms, as well as its neuropsychological functioning, neuroimaging and adverse events.

A non-systematic review was performed on PubMed database and Google Scholar, using the key words “Ayahuasca, Drug Addiction, Psychedelics, DMT, Neuroplasticity”. The review included experimental studies in humans, observational studies, systemic review articles and clinical trials.

In a randomized placebo-controlled trial, ayahuasca had a significant antidepressant effect when compared to the placebo group. Long term ayahuasca usage was associated with structural alterations in the medial parts of the brain with no evidence of increased psychopathology or worse neuropsychological functioning. According to reviewed studies the incident of prolonged psychotic reaction among ayahuasca users is rare and the causal relation with ayahuasca is sometimes difficult to establish.

Despite the promising results, more controlled double-blinded studies with larger populations are necessary to better understand the therapeutic potentials and side effects of ayahuasca.

No significant relationships.