Creative thinking and empathy are crucial for everyday interactions and subjective well-being. This is emphasized by studies showing a reduction in these skills in populations where social interaction and subjective well-being are significantly compromised (e.g., depression). Anecdotal reports and recent studies suggest that a single administration of psiloc...
A growing body of evidence shows that existential and spiritual well-being in cancer patients is associated with better medical outcomes, improved quality of life, and serves as a buffer against depression, hopelessness, and desire for hastened death. Historical and recent research suggests a role for psilocybin-assisted psychotherapy in treating cancer-rela...
Introduction: Cannabis has been historically classified as a hallucinogen. However, subjective cannabis effects do not typically include hallucinogen-like effects. Empirical reports of hallucinogen-like effects produced by cannabis in controlled settings, particularly among healthy research volunteers, are rare and have mostly occurred after administration o...
Research on the clinical applications of psychedelic-assisted psychotherapy has demonstrated promising early results for treatment of alcohol dependence. Detailed description of the content and methods of psychedelic-assisted psychotherapy, as it is conducted in clinical settings, is scarce. Methods: An open-label pilot (proof-of-concept) study of psilocybin...
How do psychedelic drugs produce their characteristic range of acute effects in perception, emotion, cognition, and sense of self? How do these effects relate to the clinical efficacy of psychedelic-assisted therapies? Efforts to understand psychedelic phenomena date back more than a century in Western science. In this article I review theories of psychedeli...
RationaleAlthough psilocybin and dextromethorphan (DXM) are hallucinogens, they have different receptor mechanisms of action and have not been directly compared.ObjectiveThis study compared subjective, behavioral, and physiological effects of psilocybin and dextromethorphan under conditions that minimized expectancy effects.MethodsSingle, acute oral doses of...
Lysergic acid diethylamide (LSD) is used recreationally and in clinical research. The aim of the present study was to characterize the pharmacokinetics and exposure-response relationship of oral LSD. We analyzed pharmacokinetic data from two published placebo-controlled, double-blind, cross-over studies using oral administration of LSD100 and 200 µg in 24 an...
BackgroundA resurgence of neurobiological and clinical research is currently underway into the therapeutic potential of serotonergic or 'classical' psychedelics, such as the prototypical psychedelic drug lysergic acid diethylamide (LSD), psilocybin (4-phosphoryloxy-N,Ndimethyltryptamine), and ayahuasca - a betacarboline- and dimethyltryptamine (DMT)-containi...
There has been growing clinical, public, and media awareness and concern about the availability and potential harmfulness of so-called 'legal highs', which are more appropriately called new or novel psychoactive substances (NPS). A cat-and-mouse process has emerged wherein unknown chemists and laboratories are producing new, and as yet nonproscribed, compoun...
Despite the widespread application of drug modelling in psychiatric research, the relative value of different models has never been formally compared in the same analysis. Here we compared the effects of five drugs (cannabis, psilocybin, amphetamine, ketamine and alcohol) in relation to psychiatric symptoms in a two-part subjective analysis. In the first par...
RationaleAlthough reports of dextromethorphan (DXM) abuse have increased recently, few studies have examined the effects of high doses of DXM.ObjectiveThis study in humans evaluated the effects of supratherapeutic doses of DXM and triazolam.MethodsSingle, acute oral doses of DXM (100, 200, 300, 400, 500, 600, 700, and 800 mg/70 kg), triazolam (0.25 and 0.5 m...
RationaleThis dose-effect study extends previous observations showing that psilocybin can occasion mystical-type experiences having persisting positive effects on attitudes, mood, and behavior.ObjectivesThis double-blind study evaluated psilocybin (0, 5, 10, 20, 30 mg/70 kg, p.o.) administered under supportive conditions.MethodsParticipants were 18 adults (1...
Psilocybin and related hallucinogenic compounds are increasingly used in human research. However, due to limited information about potential subjective side effects, the controlled medical use of these compounds has remained controversial. We therefore analysed acute, short- and long-term subjective effects of psilocybin in healthy humans by pooling raw data...
RationaleAlthough psilocybin has been used for centuries for religious purposes, little is known scientifically about its acute and persisting effects.ObjectivesThis double-blind study evaluated the acute and longer-term psychological effects of a high dose of psilocybin relative to a comparison compound administered under comfortable, supportive conditions....
The neurometabolic effects of the hallucinogen psilocybin (PSI; 0.2 mg/kg), the entactogen 3,4-methylenedioxyethylamphetamine (MDE; 2 mg/kg) and the stimulant d-methamphetamine (METH; 0.2-0.4 mg/kg) and the drugs' interactions with a prefrontal activation task were investigated in a double-blind, placebo-controlled human [F-18]fluorodeoxyglucoseFDG-positron ...
The aim of this study was to contribute to the characterization of the entactogen (ecstasy) substance group. The psychopathological, neuroendocrine and autonomic effects of common recreational doses of the entactogen 3,4-methylenedioxyethylamphetamine (MDE), the hallucinogen psilocybin, the stimulant d-methamphetamine and placebo were investigated in a doubl...
Five cases of poisoning by indigenous mushroom Hikageshibiretake (Psilocybe argentipes) are reported. As this mushroom contains psilocybin, in general, clinical features were similar to those seen by pure psilocybin. Acute toxic stuporous state with complete amnesia in the culminating period occurred in one case, psychedelic state with dreamy consciousness i...
