Hallucinogenic Drugs

Abstract

Hallucinogens constitute one of the oldest classes of drugs used by humanity, often in the context of spiritual practices. Classic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin, N,N ‐dimethyltryptamine (DMT), mescaline and 2,5‐dimethoxy‐4‐methylamphetamine (DOM) produce complex psychological and physical effects, including perceptual changes, cognitive shifts in reality and emotional alterations. These drugs primarily act on serotonin systems through 5‐hydroxytryptamine 2A (5HT 2A ) receptors, with additional activity through dopamine and glutamate systems. Investigation of the neurochemical and behavioural effects of this class of drugs has provided important insights into pharmacology and psychiatric conditions. Given their popularity as recreational drugs, investigation of their actions and effects continues to be an important endeavour. After a long hiatus, clinical studies in humans have resumed with these drugs in laboratories around the world. Key Concepts: Hallucinogens have been used for thousands of years by various societies, often in conjunction with spiritual practices. In present day, hallucinogens remain highly popular as recreational drugs. The chemical structure of hallucinogens consists of tryptamines (LSD and psilocybin) and phenethylamines (mescaline and DOM). The potency of hallucinogens is directly correlated to their ability to act as agonists at the serotonin receptor subtype, 5‐HT 2A . Drugs that act at sites other than 5‐HT 2A receptors can also produce hallucinogen‐like effects (e.g. ketamine, MDMA, salvinorin A, nitrous oxide, GHB). The signature effects of hallucinogens include perceptual changes, alterations in affect and shifts in cognitive ability. Negative responses associated with hallucinogens include ‘bad trips’ (severe anxiety and a disconnection with reality) as well as rare instances of ‘flashbacks’ and psychotic breaks. Human research with hallucinogens has recently been revitalised, augmenting the scientific advances made previously with animal studies.

Psychedelics not linked to mental health problems or suicidal behavior: A population study

“…The classical psychedelics lysergic acid diethylamide (LSD), psilocybin (magic mushrooms) and mescaline (peyote and other cacti) have their primary mechanism of action at the serotonin 2A (5-HT2A) receptor, elicit similar, often indistinguishable effects and show cross-tolerance (Bonson, 2012). Over 30 million adults in the United States (US) have tried psychedelics (approximately one in six adults aged 21–64 years) (Krebs and Johansen, 2013a).…”

“…Psychedelics are not known to harm the brain or other body organs or to cause addiction or compulsive use (Halberstadt, 2015; Bonson, 2012). Psychedelics are well known for inducing profound effects on the mind, which sometimes include confusion and emotional turmoil (McWilliams and Tuttle, 1973).…”

The link between use of psychedelic drugs and mental health problems

“…Overall, there is a lack of evidence that psychedelics increase the rate of mental health problems on a population level (Bonson, 2012; Catts and Catts, 2010). As Jorgen Bramness said in response to our population study of psychedelics and mental health: “The study shows, in agreement with previous studies, that we probably have exaggerated the danger of the use of psychedelics in general, and LSD in particular, at least if we are to judge on the basis of drug laws” (Tveito, 2013).…”