Based on its in vitro profile and preliminary evidence, 4-bromo-2,5-dimethoxyphenethylamine (2C-B) may have psychoactive properties that are similar to 3,4-methylenedioxymethamphetamine (MDMA) and psilocybin, which are investigated for the treatment of posttraumatic stress disorder and depressive disorders. We compared acute effects of 2C-B (10, 20, and 30 m...
The acute subjective effects of serotonin (5-HT)2A receptor stimulation with psilocybin in humans are mostly positive. However, negative effects such as anxiety, paranoid thinking, or loss of trust towards other people are common effects, depending on the dose administered, the personality traits of the person consuming it (set), or the environment in which ...
BACKGROUND: Patients with chronic cluster headache (CCH) suffer from poor sleep, which may impact their brain microstructure and parenchymal clearance of waste products. Psilocybin has shown promise for the treatment of CCH and has been linked to increased neuroplasticity with possible influences on brain microstructure. AIMS: To investigate the effects of p...
Maintaining effective blinding is a major methodological challenge in psychedelic research. This study provides a comprehensive evaluation of blinding integrity in 120 healthy volunteers who received either psilocybin, MDMA, or methylphenidate (active placebo) in a double-blind, randomized controlled trial. Using a multi-level assessment incorporating forced...
This pilot study will examine the safety, tolerability, acceptability, and efficacy of combination psilocybin + psychotherapy to decrease PTSD symptoms. Participants will be randomized into two different treatment groups, allowing the investigators to directly compare PE augmented with psilocybin and psilocybin-assisted psychotherapy. The Primary objective i...
PsiConnect is a large-scale neuroimaging study designed to investigate context-dependent neural and subjective effects of psilocybin using multimodal neuroimaging. It combines functional, structural, and diffusion-weighted MRI with EEG to examine brain activity in 62 participants before and after a 19 mg dose of psilocybin. The design includes resting-state ...
Affective biases are important neuropsychological mechanisms by which emotions modulate cognition, behaviour and the subjective experience of mood. Previous studies have shown that the rapid-acting antidepressant, ketamine, and serotonergic psychedelic, psilocybin, modulate affective biases in a translational rat model. Both treatments differ from convention...
Introduction: Psilocybin therapy has demonstrated efficacy for cancer-related anxiety and depression, but resource-intensive individual treatment models raise important questions for psychedelic public health about equitable access and scalability. In our prior Phase 1/2 study of group retreat psilocybin therapy for patients with metastatic cancer, we observ...
Prolonged grief disorder (PGD) affects approximately 10% of bereaved individuals and is now formally recognized in both the DSM-5-TR and ICD-11. Despite its prevalence, PGD often responds poorly to traditional therapeutic approaches. This manuscript outlines the protocol for an early-stage open-label feasibility trial investigating the use of psilocybin, a p...
BACKGROUND: Major depression is a prevalent condition among patients with life-threatening illnesses, such as cancer, and recent findings suggest that psilocybin may hold promising treatment potential. Contemporary trials of psilocybin generally employ a model that includes psychotherapeutic support consisting of preparation and integration sessions surround...
Background/Objectives: Psilocybin has re-emerged as a promising intervention for neuropsychiatric disorders including major depressive disorder, treatment-resistant depression, anxiety associated with life-threatening illness, obsessive compulsive disorder, and substance use disorders. However, conventional randomized controlled trials (RCTs)-the current gol...
The goal of this clinical trial is to learn if psilocybin, given with psychological support, is safe and helps treat anorexia nervosa in young adults. Anorexia nervosa is a serious eating disorder that currently has no approved medicine. Psilocybin is a psychedelic substance that may help the brain form new connections, which could make it easier for people ...
We carried out a systematic review of modern-era (1990-2025) placebo-controlled studies assessing the acute and post-acute effects of lysergic acid diethylamide, dimethyltryptamine and psilocybin on cognitive and psychological functions. From February 28 to March 19, 2025, PubMed and APA PsychINFO were systematically searched for placebo-controlled studies e...
Background: Although psychedelics have regained attention as potential treatment tools for various mental disorders, little research has examined their impact on temporal perception. Aims: This double-blinded placebo-controlled study aimed to investigate changes in temporal perception under psilocybin, both through performance during the Temporal Bisection T...
OBJECTIVE: The goals of this study were to examine the therapeutic effects and safety of psilocybin given as a pulsed regimen for the prevention of migraine and to consider the blinding integrity of an active control agent. BACKGROUND: The administration of a single low dose of psilocybin was observed to have lasting therapeutic effects in one small pilot tr...
Psilocybin is a classic psychedelic drug known to alter subjective experience and elicit long-term psychological changes, enhancing cognitive flexibility and reducing rigid self-related beliefs. Combined with compassion motivational primes that involve generating mental representations of compassion, it may increase the potential for activating the care-affi...
BACKGROUND AND AIMS: There is an urgent unmet need for novel treatments for methamphetamine (MA) use disorder. We explored the qualitative experiences of people participating in a study of psilocybin-assisted psychotherapy (PAT) to treat MA use disorder. DESIGN AND SETTING: Qualitative study of participants enrolled in a single arm, open-label pilot study of...
Introduction: The subjective effects of psilocybin on obsessive-compulsive disorder (OCD) are under-explored. Therefore, we conducted a qualitative study of participant experiences from the first randomized placebo-controlled trial of single-dose psilocybin combined with unstructured and non-directive support for individuals with treatment-refractory OCD. Ou...
PURPOSE/BACKGROUND: The therapeutic effects of psilocybin treatment are thought to be influenced by the subjective dose-dependent psychedelic experience, as well as the individual participant's mindset and the treatment environment. However, the relative contribution of an individual's pretreatment clinical characteristics and their subjective psychedelic ex...
Humphry Osmond coined the term ‘psychedelic’ in 1956, conjoining ‘psyche’ for ‘soul’ and ‘delic’ from ‘dêlos’ for ‘to manifest’ or ‘illuminate.’ Soul-illumination is an adjective that describes a psychological state or process. However, Osmond’s intention was to use the adjective to name- not just a state- but a category of drug that can induce the subjectiv...
