While the exploration of serotonergic psychedelics as psychiatric medicines deepens, so does the pressure to better understand how these compounds act on the brain. We used a double-blind, placebo-controlled, crossover design and administered lysergic acid diethylamide (LSD), 3,4-methylenedioxymethamphetamine (MDMA), and d-amphetamine in 25 healthy participants. By using spectral dynamic causal...
3,4-Methylenedioxymethamphetamine (MDMA) is an entactogen with therapeutic potential. The two enantiomers of MDMA differ regarding their pharmacokinetics and pharmacodynamics but the chiral pharmacology of MDMA needs further study in clinical trials. Here, an achiral and an enantioselective high performance liquid chromatography-tandem mass spectrometry method for the quantification of MDMA and...
In vivo , psilocybin is rapidly dephosphorylated to psilocin which induces psychedelic effects by interacting with the 5-HT 2A receptor. Psilocin primarily undergoes glucuronidation or conversion to 4-hydroxyindole-3-acetic acid (4-HIAA). Herein, we investigated psilocybin’s metabolic pathways in vitro and in vivo , conducting a thorough analysis of the enzymes involved. Metabolism studies were...
The anxiolytic and sedative-like effects of 3-methyl-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole (DM506), a non-hallucinogenic compound derived from ibogamine, were studied in mice. The behavioral effects were examined using Elevated O-maze and novelty suppressed feeding (NSFT) tests, open field test, and loss of righting reflex (LORR) test. The results showed that 15 mg/kg DM506 induced acute...
Psychedelic compounds, including psilocybin, LSD (lysergic acid diethylamide), DMT (N,N -dimethyltryptamine), and 5-MeO-DMT (5-methoxy-N,N-dimethyltryptamine), all of which are serotonin 2A receptor agonists, are being investigated as potential treatments. This review aims to summarize the current clinical research on these 4 compounds and mescaline to guide future research. Their mechanism(s)...
Psychedelic drugs including psilocybin and LSD are undergoing clinical trials for a range of psychiatric and neurological conditions, and have particularly shown substantial promise in phase 2 studies of depression. In this article we outline key knowledge gaps that may be imperative for a successful implementation of psychedelic drugs as medicines as identified by members of the European...
Psilocybin is being studied for its therapeutic potential in various mental health disorders, such as depression, anxiety, and addiction. Initial studies suggested that psilocybin is generally safe when used under controlled conditions, but more research is needed to better understand its safety profile. We report safety pharmacology data from a pooled analysis of three randomized crossover...
Lysergic acid diethylamide (LSD) is currently investigated for several neurological and psychiatric illnesses. Various studies have investigated the pharmacokinetics and the pharmacokinetic-pharmacodynamic relationship of LSD in healthy participants, but data on urinary recovery and confirmatory studies are missing. The present study characterized the pharmacokinetics,...
There is renewed interest in the use of lysergic acid diethylamide (LSD) in psychiatric research and practice. Although acute subjective effects of LSD are mostly positive, negative subjective effects, including anxiety, may occur. The induction of overall positive acute subjective effects is desired in psychedelic-assisted therapy because positive acute experiences are associated with greater...
Background: Research with the Psychedelic Experience Questionnaire/Scale (PES) focuses on questions relating to mystical experience (Mystical Experience Questionnaire (MEQ)). The psychometric potential of the non-MEQ items of the PES remains largely unexplored. Aims: We investigated whether the PES also yields subscales besides the MEQ30 subscales. Methods: Data from 239 PES measurements (140...
Background: The interest in psychoactive agents for treating mental disorders has gathered a growing body of scientific interest. However, research on the relationship between altered states of consciousness (ASCs) and ketamine's antidepressant properties is still limited. Likewise, approaches to sustain early treatment success for the long-term are needed. Taking both aspects into account, the...
Mescaline, lysergic acid diethylamide (LSD), and psilocybin are classic serotonergic psychedelics. A valid, direct comparison of the effects of these substances is lacking. The main goal of the present study was to investigate potential pharmacological, physiological and phenomenological differences at psychoactive-equivalent doses of mescaline, LSD, and psilocybin. The present study used a...
Abstract Disclosure: C. Atila: None. F. Holze: None. R. Murugesu: None. N. Rommers: None. N. Hutter: None. N. Varghese: None. C.O. Sailer: None. A. Eckert: None. M. Heinrichs: None. M. Liechti: None. M. Christ-crain: None. Introduction: Despite adequate treatment, patients with arginine vasopressin deficiency (AVP-D), known as central diabetes insipidus (cDI), often report psychological...
Disruptions of the hypothalamic-pituitary axis can cause an arginine vasopressin deficiency, also known as central diabetes insipidus. Patients with this condition are at high risk of additional oxytocin deficiency owing to the close anatomical proximity of oxytocin-producing neurons; however, no conclusive evidence for such a deficiency has been reported. We aimed to use...
N,N-dimethyltryptamine (DMT) is distinct among classic serotonergic psychedelics because of its short-lasting effects when administered intravenously. Despite growing interest in the experimental and therapeutic use of intravenous DMT, data are lacking on its clinical pharmacology. We conducted a double-blind, randomized, placebo-controlled crossover trial in 27 healthy participants to test...
Abstract Psychedelics have emerged as promising candidate treatments for various psychiatric conditions, and given their clinical potential, there is a need to identify biomarkers that underlie their effects. Here, we investigate the neural mechanisms of lysergic acid diethylamide (LSD) using regression dynamic causal modelling (rDCM), a novel technique that assesses whole-brain effective...
This study aimed to investigate the efficacy and safety of lysergic acid diethylamide (LSD)-assisted therapy in patients who experienced anxiety with or without association with a life-threatening illness. The study is an investigator-initiated 2-center trial that used a double-blind, placebo-controlled, 2-period, random-order, crossover design with 2 sessions with either oral LSD (200 μg) or...
Classic psychedelics have been shown to exert therapeutic potential for the treatment of various psychiatric disorders, neuropsychiatric diseases, and neuronal damage. Besides their psychopharmacological activity, psychedelics have been reported to modulate immune functions. There has thus far been a sparse exploration of the direct immune-modulating effect of psychedelics on human immune cells...
Psilocybin is being investigated as a potential treatment for psychiatric and neurological disorders. Only a few studies have evaluated the pharmacokinetics (PKs) of psilocybin and have used body weight‐adjusted dosing. Data on PKs and the PK‐pharmacodynamic (PD) relationship of fixed doses that are commonly used are unavailable. The present study characterized the PKs and PK‐PD relationship of...
Abstract Rationale 4-Thio-substituted phenylalkylamines such as 2,5-dimethoxy-4-ethylthiophenethylamine (2C-T-2) and 2,5-dimethoxy-4- n -propylthiophenethylamine (2C-T-7) produce psychedelic effects in humans and have been distributed as recreational drugs. Objectives The present studies were conducted to examine the structure–activity relationships (SAR) of a series of 4-thio-substituted...
Abstract Background Lysergic acid diethylamide (LSD) is currently being investigated in psychedelic-assisted therapy. LSD has a long duration of acute action of 8–11 hours. It produces its acute psychedelic effects via stimulation of the serotonin 5-hydroxytryptamine-2A (HT2A) receptor. Administration of the 5-HT2A antagonist ketanserin before LSD almost fully blocks the acute subjective...
To investigate if clinical features associated with acute cannabis intoxication in patients presenting to Emergency Departments for medical assistance differ according to patient age and sex. We analysed presentations in the Euro-DEN Plus dataset from 2014 to 2019 in which cannabis was the only drug involved (except for alcohol), and age, sex and alcohol co-ingestion had been recorded. Age was...
Background: Cognition that is not dominated by thinking in terms of opposites (opposite diminishing) or by making judgments (non-judging) can be found both in Buddhist/mindfulness contexts and in mental states that are fostered by dissociative psychedelics (N-methyl-D-aspartate antagonists) such as ketamine. Especially for the Buddhist/mindfulness case, both opposite diminishing and non-judging...
Background: 3,4-Methylenedioxymethamphetamine (MDMA) has shown initial promise as an adjunct in psychotherapy to treat posttraumatic stress disorder (PTSD). Its efficacy and safety have been demonstrated across phase I–III studies. However, the mechanism underlying the potential utility of MDMA to treat PTSD in humans has not yet been thoroughly investigated. Preliminary evidence suggests that...
Objective and hypothesis 4‐Substituted derivatives of 2,5‐dimethoxyamphetamine (referred to as DOX derivatives) exhibit psychedelic and euphoria‐inducing effects, mainly mediated by 5‐HT 2A receptor activation; for this reason, they are used recreationally but also bear therapeutic potential. Studies in humans and animals revealed that 4‐substitution with halogens results in high clinical...