ABSTRACT Psychedelics such as psilocybin and lysergic acid diethylamide (LSD) exert hallucinogenic effects through stimulation of serotonin 5-HT2A receptors (5-HT2ARs) in the cerebral cortex. In recent years, numerous reports have demonstrated that psychedelics are effective in treating various psychiatric disorders such as major depressive disorder (MDD), t...
A Phase 1 trial comprising 15 patients has found that repeated high-dose administration of psilocybin was more effective than low-dose psilocybin or placebo in reducing symptoms of obsessive-compulsive disorder (OCD). Psilocybin was generally well-tolerated, with no reports of serious adverse events.
BackgroundPosttraumatic stress disorder (PTSD) and major depressive disorder are often comorbid in humans. Psilocybin reportedly has beneficial therapeutic effects on depression, possibly by promoting neuroplasticity. PTSD is associated with the dysregulation of neuroplasticity in the hippocampus and medial prefrontal cortex (mPFC). We hypothesized that psil...
In the past decade, interest in studying psychedelic compounds as potential therapeutic agents has resurged. These studies carefully exclude individuals at risk for developing psychotic symptoms in response to psychedelic use. Given the potential for psychedelics to be established as treatments in psychiatry, it is important to more robustly understand their...
BACKGROUND: Major depressive disorder is one of the most debilitating psychiatric disorders worldwide. First-line treatments such as selective serotonin reuptake inhibitors have significant limitations, including delayed onset of therapeutic effects and treatment resistance in about 30% of patients. Increasing evidence suggests that acute administration of s...
Patients with treatment-resistant depression who received psilocybin-assisted psychotherapy showed clinically meaningful improvement in depressive symptoms relative to placebo, a Phase 2b trial has found. However, the study did not show a significant effect on the primary outcome of treatment response 6 weeks after the first of two doses of psilocybin. Study...
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...
BACKGROUND: Psilocybin is among the serotonergic psychedelics closest to potential FDA approval, with growing evidence of therapeutic benefit across psychiatric conditions. As clinical trials expand, systematic characterization of adverse events (AEs) remains essential. While transient hypertensive responses are well documented, hypotensive events such as ne...
Psychedelic-assisted therapy (PAT) has demonstrated substantial efficacy across a range of mental disorders. However, heterogeneity between patients confers differential responsiveness. This systematic review aims to explore factors which may predict therapeutic responses to PAT. A systematic search was performed from inception through to March 2024 and stud...
Psychedelic drugs are increasingly under investigation as potential therapeutic agents for mental health conditions and are being increasingly used recreationally. Psychedelic use may result in an episode of intense psychological distress, commonly referred to as a "bad trip." Bad trips represent a potentially volatile, erratic, and dangerous situation, whic...
While psychedelics have shown initial promise in the treatment of migraine, experimental studies have relied on small and homogenous samples, which limit the reliability and generalizability of findings. These limitations underscore the complementary value of other research designs that leverage larger and more representative samples. This cross-sectional st...
This commentary critically examines the interpretation and analytic choices in Goodwin et al.’s (2026) analysis of therapeutic alliance in psilocybin treatment for treatment-resistant depression. While the authors conclude that alliance did not meaningfully contribute to treatment efficacy, we argue that this interpretation is not supported by the reported r...
BACKGROUND: Current treatments for obsessive-compulsive disorder (OCD), including serotonin reuptake inhibitors and cognitive-behavioral therapy, are often insufficient. Psilocybin, a 5HT2a agonist psychedelic, has shown promise for treating OCD, but rigorous evidence is still needed. AIMS: This randomized clinical trial evaluated safety, tolerability, and b...
In Canada, the use of both prescription medications and psychedelics has become increasingly prevalent. As of 2022, approximately 16.5% of Canadians-about 6.3 million individuals-were prescribed at least one antidepressant, with fluoxetine remaining one of the most commonly used options (IQVIA, 2023). Benzodiazepine use, including drugs like alprazolam, rang...
Psilocybin is a hallucinogen with complex neurobiological and behavioral effects. Underlying these effects are changes in brain neuroplasticity. We hypothesized psilocybin given during adolescence, a time of heightened neuroplasticity, particularly in the forebrain, would affect emotional behavior and the associated underlying neuroanatomy, neurocircuitry, a...
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...
