"Magic mushrooms" is the most common name given to hallucinogenic fungi containing the psychoactive alkaloids psilocybin and psilocin. In recent years, fungis' sclerotia, commonly called "magic truffles" have become a form of supply of psychoactive Psilocybe alkaloids since Psilocybe sclerotia are not specifically included in the laws banning the sale, the p...
Introduction and aimsSimultaneous polysubstance use (SPU) is a common phenomenon, yet little is known about its role in substance use initiation.Design and methodsIn 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, th...
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...
ContextResearchers conducted extensive investigations of hallucinogens in the 1950s and 1960s. By the early 1970s, however, political and cultural pressures forced the cessation of all projects. This investigation reexamines a potentially promising clinical application of hallucinogens in the treatment of anxiety reactive to advanced-stage cancer.ObjectiveTo...
Psilocybin has been used for centuries for religious purposes; however, little is known scientifically about its long-term effects. We previously reported the effects of a double-blind study evaluating the psychological effects of a high psilocybin dose. This report presents the 14-month follow-up and examines the relationship of the follow-up results to dat...
Action of a hallucinogenic substance, psilocybin, on internal time representation was investigated in two double-blind, placebo-controlled studies: Experiment 1 with 12 subjects and graded doses, and Experiment 2 with 9 subjects and a very low dose. The task consisted in repeated reproductions of time intervals in the range from 1.5 to 5s. The effects were a...
Schizophrenia patients exhibit impairments in prepulse inhibition (PPI) of the startle response. Hallucinogenic 5-HT(2A) receptor agonists are used for animal models of schizophrenia because they mimic some symptoms of schizophrenia in humans and induce PPI deficits in animals. Nevertheless, one report indicates that the 5-HT(2A) receptor agonist psilocybin ...
Hallucinogenic psilocybin is known to alter the subjective experience of time. However, there is no study that systematically investigated objective measures of time perception under psilocybin. Therefore, we studied dose-dependent effects of the serotonin (5-HT)2A/1A receptor agonist psilocybin (4-phosphoryloxy-N, N-dimethyltryptamine) on temporal processin...
The recurrence of flashbacks without acute or chronic hallucinogen consumption has been recognized in the DSM IV criteria as the hallucinogen persisting perception disorder (HPPD). Perceptual disturbances may last for 5 years or more and represent a real psychosocial distress. We reported here a case of a 18-year-old young man presenting HPPD after a mixed i...
PrincipleThe various mushroom poisoning syndromes are summarised together with elements underlining uncertainty and lack of knowledge. For each of the classical syndromes concerned, classified in delays inferior or superior to 6 hours, the toxins and their mechanisms of action, the main mushrooms responsible, the symptoms and their treatment are all presente...
In the context of excessive use of natural or synthetic psychoactive substances, with stimulating, psychedelic and hallucinogenic effects, an increase, if not a recurrence, in consumption of Psilocybe semilanceata has been observed in France over some fifteen years. Psilocybin and psilocin are the active compounds, responsible for the hallucinogenic effects ...
Tryptamine produces pharmacologic effects in man and the chronic spinal dog which are similar to those produced by LSD, mescaline, psilocin, DMT, DOM and DOB. These effects include tachycardia, tachypnea, mydriasis, hyperreflexia, behavioral changes and in man, hallucinations. Chronic spinal dogs treated chronically with LSD became tolerant to its ability to...
The objective was to determine the behavioral effects and duration of action of bromocriptine (BC) doses from 6 to 60 mg/kg i.p. Cats were housed in large outdoors cages designed for prolonged observation using an ethological approach. Baseline behavior was measured after a 3 month period of habituation. The frequency of 12 behaviors was then scored continuo...
Previous studies from our laboratory have demonstrated that there are a number of important dissociations between the effects of hallucinogenic drugs on the activity of serotonin-containing dorsal raphe neurons and behavior in freely moving cats. In the present study, we extended this analysis to serotonergic units in the nucleus centralis superior (NCS) and...
The disruption of the temporal distribution of investigatory responses by rats in a novel hole-board following lysergic acid diethylamide-25 (LSD), as described in a companion paper (Geyer and Light, 1979), was found to be a characteristic effect of a variety of hallucinogens. Similar effects were produced by indoleamine hallucinogens, such as LSD, N,N-dimet...
Tactile startle responding by male Sprague-Dawley rats given 60 presentations of air-puff stimuli (37.5 psi) was measured after the intraperitoneal administration of graded doses of hallucinogens and other psychoactive drugs. Among the drugs tested were the indoleamine-derived compounds, lysergic acid diethylamide (LSD), N,N-dimethyltryptamine and psilocin, ...
The hallucinogenic indoleamine drugs N,N-dimethyltryptamine (N,N-DMT), psilocybin, bufotenin, 5-methoxy-N,N-dimethyltryptamine, and N-methyltryptamine, increased rat plasma prolactin (PRL) levels. The increase in plasma PRL produced by N,N-DMT, psilocybin, and bufotenin was inhibited by methysergide, a serotonin receptor blocker. Parachlorophenylalanine (PCP...
The startle reflex was measured in 7 groups of 10 rats each after intraperitoneal injection of saline or 0.25, 0.50, 0.75, 1.0, 2.0, 4.0 or 8.0 mg/kg psilocybin. Low doses (0.75-2.0 mg/kg) increased startle amplitude whereas high doses (4.0-8.0 mg/kg) depressed startle. Selected low (0.71 mg/kg) or high (5.70 mg/kg) doses of psilocin also had a biphasic dose...
Male albino rats were trained to respond differentially on the left or right lever in a 2-lever chamber on the basis of which drug had been given intra-peritoneally (IP) 30 min before experimentation. In 1 group 1.9 mg/kg of delta9-THC and control injections (vehicle) served as the discriminative stimuli associated with each lever and in another group the dr...
