Psychedelic drugs have long been known to be capable of inducing mystical or transcendental experiences. However, given the common "recreational" nature of much present-day psychedelic use, with typical doses tending to be lower than those commonly taken in the 1960s, the extent to which illicit use of psychedelics today is associated with mystical experiences is not known. Furthermore the mild...
Abstract Aims It is still unclear if cognitive abnormalities in human 3,4‐methylenedioxymeth‐amphetamine ( MDMA ) users existed before the beginning of use or if other confounders could explain the deficits. The present study was conducted in order to assess the relationship between beginning MDMA use and subsequent cognitive performance and to overcome previous methodological shortcomings....
Abstract Introduction and Aims. Simultaneous polysubstance use (SPU) is a common phenomenon, yet little is known about its role in substance use initiation. Design and Methods. In the present study, 226 cannabis users completed structured interviews about their substance use history. For each substance ever used, participants provided details of their age of first use, their use in the...
The prevalent view today is that schizophrenia is a syndrome rather than a specific disease. Liability to schizophrenia is highly heritable. It appears that multiple genetic and environmental factors operate together to push individuals over a threshold into expressing the characteristic clinical picture. One environmental factor which has been curiously neglected is the evidence that certain...
Drug interaction with P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) may influence its tissue disposition including blood-brain barrier transport and result in potent drug-drug interactions. The limited data obtained using in-vitro models indicate that methadone, buprenorphine, and cannabinoids may interact with human P-gp; but almost nothing is known about drugs of abuse and...
This study used a web-based questionnaire to investigate user perceptions of the benefits and harms of hallucinogenic drug use. Over 600 forms were submitted. Users were asked to comment on the acute and prolonged effects of different drugs and to provide more specific information on how particular drugs have harmed and/or helped them. Subjects reported relatively less harm associated with the...
Ayahuasca is a psychoactive beverage used for magico-religious purposes in the Amazon. Recently, Brazilian syncretic churches have helped spread the ritual use of ayahuasca abroad. This trend has raised concerns that regular use of this N,N-dimethyltryptamine-containing tea may lead to the medical and psychosocial problems typically associated with drugs of abuse. Here we assess potential drug...
Increase in recreational ketamine use may be a cause for concern. We aimed here at assessing, in a sample of ketamine misusers, concordance between the typical near-death experience (NDE) features and the on-drug psychoactive effects the subjects experienced. In 2003-2005, a sample of previous ketamine misusers recollecting a ketamine-related NDE were recruited through snowballing and screened...
OBJECTIVE: The last decade has seen increasing evidence of dysfunctions in the endogenous cannabinoid system in schizophrenia and of its relationship with the typical cognitive impairment of the disorder. Studies in animal models, healthy volunteers, and psychotic patients clearly suggest an antipsychotic-like effect of cannabidiol. This study investigated the effects of cannabidiol on...
Delta(9)-Tetrahydrocannabinol (Delta(9)-THC), the principal psychoactive constituent of the Cannabis sativa plant, and other agonists at the central cannabinoid (CB(1)) receptor may induce characteristic psychomotor effects, psychotic reactions and cognitive impairment resembling schizophrenia. These effects of Delta(9)-THC can be reduced in animal and human models of psychopathology by two...