Psychedelics are a subclass of
hallucinogenic drugs
Hallucinogens are a large, diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Most hallucinogens can be categorize ...
whose primary effect is to trigger non-ordinary states of consciousness (known as
psychedelic experience
A psychedelic experience (known colloquially as a trip) is a temporary altered state of consciousness induced by the consumption of a psychedelic substance (most commonly LSD, mescaline, psilocybin mushrooms, or DMT). For example, an acid tr ...
s or "trips").
[Pollan, Michael (2018). ''How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence''] Sometimes, they are called classic hallucinogens, serotonergic hallucinogens, or serotonergic psychedelics, and the term ''psychedelics'' is used more broadly to include all
hallucinogens; this article uses the narrower definition of ''psychedelics''. Psychedelics cause specific psychological, visual, and auditory changes, and often a substantially
altered state of consciousness.
[Leary, Timothy; Metzner, Ralph (1964). ''The Psychedelic Experience: A Manual Based on The Tibetan Book of the Dead''] Psychedelic states are often compared to
meditative,
psychodynamic or
transcendental
Transcendence, transcendent, or transcendental may refer to:
Mathematics
* Transcendental number, a number that is not the root of any polynomial with rational coefficients
* Algebraic element or transcendental element, an element of a field exten ...
types of alterations of mind.
The "classical" psychedelics, the psychedelics with the largest scientific and cultural influence, are mescaline
Mescaline or mescalin (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin.
Biological sou ...
, LSD, psilocybin, and DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
.
Most psychedelic drugs fall into one of the three families of chemical compounds: tryptamines
Substituted tryptamines, or serotonin analogues, are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring, joined to an amino (NH2) group via an ethy ...
, phenethylamines
Substituted phenethylamines (or simply phenethylamines) are a chemical class of organic compounds that are based upon the phenethylamine structure; the class is composed of all the derivative compounds of phenethylamine which can be formed by ...
, or lysergamides. They act via serotonin 2A receptor agonism. When compounds bind to serotonin 5-HT2A receptors, they modulate the activity of key circuits in the brain involved with sensory perception and cognition, however, the exact nature of how psychedelics induce changes in perception and cognition via the 5-HT2A receptor is still unknown, although reduction in default mode network
In neuroscience, the default mode network (DMN), also known as the default network, default state network, or anatomically the medial frontoparietal network (M-FPN), is a large-scale brain network primarily composed of the dorsal medial prefro ...
activity and increased functional connectivity
Resting state fMRI (rs-fMRI or R-fMRI) is a method of functional magnetic resonance imaging (fMRI) that is used in brain mapping to evaluate regional interactions that occur in a resting or task-negative state, when an explicit task is not being ...
between regions in the brain as a result may be one of the most relevant pharmacological mechanisms underpinning the psychedelic experience
A psychedelic experience (known colloquially as a trip) is a temporary altered state of consciousness induced by the consumption of a psychedelic substance (most commonly LSD, mescaline, psilocybin mushrooms, or DMT). For example, an acid tr ...
, particularly ego death. The psychedelic experience is often compared to non-ordinary forms of consciousness such as those experienced in meditation
Meditation is a practice in which an individual uses a technique – such as mindfulness, or focusing the mind on a particular object, thought, or activity – to train attention and awareness, and achieve a mentally clear and emotionally cal ...
, mystical experiences, and near-death experiences, which also appear to be partially underpinned by altered default mode network
In neuroscience, the default mode network (DMN), also known as the default network, default state network, or anatomically the medial frontoparietal network (M-FPN), is a large-scale brain network primarily composed of the dorsal medial prefro ...
activity. The phenomenon of ego death is often described as a key feature of the psychedelic experience.
Many psychedelic drugs are illegal worldwide under the UN conventions, with occasional exceptions for religious use or research contexts. Despite these controls, recreational use of psychedelics is common. Legal barriers have made the scientific study of psychedelics more difficult. Research has been conducted, however, and studies show that psychedelics are physiologically safe and rarely lead to addiction
Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use o ...
. Studies conducted using psilocybin in a psychotherapeutic
Psychotherapy (also psychological therapy, talk therapy, or talking therapy) is the use of psychological methods, particularly when based on regular personal interaction, to help a person change behavior, increase happiness, and overcome prob ...
setting reveal that psychedelic drugs may assist with treating depression, alcohol addiction, and nicotine addiction
Nicotine is a natural product, naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreational drug use, recreationally as a stimulant and anxiolytic. As ...
. Although further research is needed, existing results suggest that psychedelics could be effective treatments for certain forms of psychopathology. Proponents believe that the increase in consumption of psychedelics in defiance of the law is likely to result in more widespread legalization and decriminalization of the substances (as was the case with cannabis). In 2022, 28% of Americans have tried psychedelics.
Etymology and nomenclature
The term ''psychedelic
Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary states of consciousness (known as psychedelic experiences or "trips").Pollan, Michael (2018). ''How to Change Your Mind: What the New Science of ...
'' was coined by the psychiatrist Humphrey Osmond
Humphry Fortescue Osmond (1 July 1917 – 6 February 2004) was an English psychiatrist who expatriated to Canada, then moved to work in the United States. He is known for inventing the word ''psychedelic'' and for his research into interesting a ...
during written correspondence with author Aldous Huxley and presented to the New York Academy of Sciences by Osmond in 1957. It is irregularly derived from the Greek words ψυχή ''psychḗ'' 'soul, mind' and δηλείν ''dēleín'' 'to manifest', with the intended meaning "mind manifesting," the implication being that psychedelics can reveal unused potentials of the human mind. The term was loathed by American ethnobotanist
Ethnobotany is the study of a region's plants and their practical uses through the traditional knowledge of a local culture and people. An ethnobotanist thus strives to document the local customs involving the practical uses of local flora for m ...
Richard Schultes
Richard Evans Schultes (''SHULL-tees'';Jonathan Kandell ''The New York Times'', April 13, 2001, Accessed April 26, 2020. January 12, 1915 – April 10, 2001) was an American biologist. He may be considered the father of modern ethnobotany. He i ...
but championed by American psychologist Timothy Leary.
Aldous Huxley had suggested his own coinage ''phanerothyme'' (Greek ''phaneroein''- "visible" and Greek ''thymos'' "soul", thus "visible soul") to Osmond in 1956. Recently, the term entheogenic has come into use to denote the use of psychedelic drugs, as well as various other types of psychoactive substances, in a religious, spiritual, and mystical context.
In 2004, David E. Nichols
David Earl Nichols (born December 23, 1944, Covington, Kentucky) is an Americans, American pharmacologist and medicinal chemist.
Previously the Robert C. and Charlotte P. Anderson Distinguished Chair in Pharmacology at Purdue University, Nichol ...
wrote the following about the nomenclature used for psychedelic drugs:
Robin Carhart-Harris and Guy Goodwin write that the term ''psychedelic'' is preferable to ''hallucinogen'' for describing classical psychedelics because of the term ''hallucinogen''s "arguably misleading emphasis on these compounds' hallucinogenic properties."
While the term ''psychedelic'' is most commonly used to refer only to serotonergic hallucinogens, it is sometimes used for a much broader range of drugs, including empathogen–entactogens, dissociatives, and atypical hallucinogens such as ''salvia divinorum
''Salvia divinorum'' (Latin: "sage of the diviners"; also called ska maría pastora, seer's sage, yerba de la pastora, magic mint or simply salvia) is a plant species with transient psychoactive properties when its leaves are consumed by che ...
''. Thus, the term ''serotonergic psychedelic'' is sometimes used for the narrower class. It is important to check the definition of a given source. This article uses the more common, narrower definition of ''psychedelic''.
Examples
* LSD (Lysergic acid diethylamide) is a derivative of lysergic acid
Lysergic acid, also known as -lysergic acid and (+)-lysergic acid, is a precursor for a wide range of ergoline alkaloids that are produced by the ergot fungus and found in the seeds of '' Turbina corymbosa'' (ololiuhqui), '' Argyreia nervosa'' ...
, which is obtained from the hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water ...
of ergotamine. Ergotamine is an alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...
found in the fungus '' claviceps purpurea'', which primarily infects rye. LSD is both the prototypical psychedelic and the prototypical lysergamide. As a lysergamide, LSD contains both a tryptamine and phenethylamine
Phenethylamine (PEA) is an organic compound, natural monoamine alkaloid, and trace amine, which acts as a central nervous system stimulant in humans. In the brain, phenethylamine regulates monoamine neurotransmission by binding to trace amin ...
group within its structure. As a result of containing a phenethylamine group LSD agonises dopamine receptors as well as serotonin receptors, making it more energetic in effect in contrast to the more sedating effects of psilocin, which isn't a dopamine agonist.
* Psilocin (4-HO-DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
) is the dephosphorylated active metabolite An active metabolite is an active form of a drug after it has been processed by the body.
Metabolites of drugs
An active metabolite results when a drug is metabolized by the body into a modified form which continues to produce effects in the body ...
of the indole alkaloid
Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known differe ...
psilocybin and a substituted tryptamine
Substituted tryptamines, or serotonin analogues, are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring, joined to an amino group, amino (NH2) group ...
, which is produced in over 200 species of fungi. Of the Classical psychedelics psilocybin has attracted the greatest academic interest regarding its ability to manifest mystical experiences, although all psychedelics are capable of doing so to variable degrees. ''O''-Acetylpsilocin (4-AcO-DMT) is an acetylated analog of psilocin. Additionally, replacement of a methyl group at the dimethylated nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
with an isopropyl or ethyl group yields 4-HO-MIPT
4-HO-MiPT (miprocin, 4-hydroxy-''N''-methyl-''N''-isopropyltryptamine) is a synthetic substituted aromatic compound and a lesser-known psychedelic tryptamine. It is thought to be a serotonergic psychedelic, similar to magic mushrooms, LSD and ...
and 4-HO-MET
4-HO-MET (4-hydroxy-''N''-methyl-''N''-ethyltryptamine, metocin, or methylcybin), is a lesser-known psychedelic drug. It is a structural− and functional analog of psilocin as well as the 4-hydroxyl analog of methylethyltryptamine (MET). 4-HO-M ...
, respectively.
* Mescaline
Mescaline or mescalin (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin.
Biological sou ...
(3,4,5-trimethoxyphenethylamine) is a phenethylamine
Phenethylamine (PEA) is an organic compound, natural monoamine alkaloid, and trace amine, which acts as a central nervous system stimulant in humans. In the brain, phenethylamine regulates monoamine neurotransmission by binding to trace amin ...
alkaloid found in various species of cacti, the most well known being Peyote
The peyote (; ''Lophophora williamsii'' ) is a small, spineless cactus which contains psychoactive alkaloids, particularly mescaline. ''Peyote'' is a Spanish word derived from the Nahuatl (), meaning "caterpillar cocoon", from a root , "to gl ...
(''Lophophora williamsii'') and San Pedro (''Echinopsis pachanoi)''. Mescaline has effects comparable to those of LSD and psilocybin, albeit with a greater emphasis on colors and patterns.
* DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
(N,N-dimethyltryptamine) is an indole alkaloid
Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known differe ...
found in various species of plants. Traditionally it is consumed by tribes in South America in the form of ayahuasca
AyahuascaPronounced as in the UK and in the US. Also occasionally known in English as ''ayaguasca'' (Spanish-derived), ''aioasca'' (Brazilian Portuguese-derived), or as ''yagé'', pronounced or . Etymologically, all forms but ''yagé'' descen ...
. A brew is used that consists of DMT-containing plants as well as plants containing MAOIs
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especia ...
, specifically harmaline, which allows DMT to be consumed orally without being rendered inactive by monoamine oxidase
Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The first ...
enzymes in the digestive system. In the Western world DMT is more commonly consumed via the vaporisation of freebase DMT. Whereas Ayahuasca typically lasts for several hours, inhalation has an onset measured in seconds and has effects measured in minutes, being significantly more intense. Particularly in vaporised form, DMT has the ability to cause users to enter a hallucinatory realm fully detached from reality, being typically characterised by hyperbolic geometry, and described as defying visual or verbal description. Users have also reported encountering and communicating with entitites within this hallucinatory state. DMT is the archetypal substituted tryptamine
Substituted tryptamines, or serotonin analogues, are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring, joined to an amino group, amino (NH2) group ...
, being the structural scaffold of psilocybin and - to a lesser extent - the lysergamides.
* 2C-B
2C-B (4-Bromo-2,5-dimethoxyphenethylamine) is a psychedelic drug of the 2C family. It was first synthesized by Alexander Shulgin in 1974. In Shulgin's book '' PiHKAL'', the dosage range is listed as 12–24 mg. As a recreational drug, 2C-B is so ...
(2,5-dimethoxy-4-bromophenethylamine) is a substituted phenthylamine first synthesised in 1974 by Alexander Shulgin
Alexander Theodore "Sasha" Shulgin (June 17, 1925 – June 2, 2014) was an American medicinal chemist, biochemist, organic chemist, pharmacologist, psychopharmacologist, and author. He is credited with introducing 3,4-methylenedioxymethamph ...
. 2C-B is both a psychedelic and a mild entactogen, with its psychedelic effects increasing and its entactogenic effects decreasing with dosage. 2C-B is the most well known compound in the 2C family
2C (2C-''x'') is a general name for the family of psychedelic phenethylamines containing methoxy groups on the 2 and 5 positions of a benzene ring. Most of these compounds also carry lipophilic substituents at the 4 position, usually resulting in ...
, their general structure being discovered as a result of modifying the structure of mescaline.
Uses
Traditional
Psychedelics have a long history of use in traditional medicine
Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...
and traditional religion, for their perceived ability to promote physical and mental healing. In this context, they are often known as entheogens. Native American practitioners using mescaline-containing cacti (most notably peyote
The peyote (; ''Lophophora williamsii'' ) is a small, spineless cactus which contains psychoactive alkaloids, particularly mescaline. ''Peyote'' is a Spanish word derived from the Nahuatl (), meaning "caterpillar cocoon", from a root , "to gl ...
, San Pedro, and Peruvian torch
''Echinopsis peruviana'' (syn. ''Trichocereus peruvianus''), the Peruvian torch cactus, is a fast-growing columnar cactus native to the western slope of the Andes in Peru, between about above sea level.
Description
The plant is bluish-green i ...
) have reported success in treating alcoholism
Alcoholism is, broadly, any drinking of alcohol (drug), alcohol that results in significant Mental health, mental or physical health problems. Because there is disagreement on the definition of the word ''alcoholism'', it is not a recognize ...
, and Mazatec practitioners routinely use psilocybin mushrooms for divination and healing. The psychoactive brew ayahuasca
AyahuascaPronounced as in the UK and in the US. Also occasionally known in English as ''ayaguasca'' (Spanish-derived), ''aioasca'' (Brazilian Portuguese-derived), or as ''yagé'', pronounced or . Etymologically, all forms but ''yagé'' descen ...
is used in Peru and other parts of South America for spiritual and physical healing as well as in religious festivals.
A number of frequently mentioned or traditional psychedelics such as ''Ayahuasca
AyahuascaPronounced as in the UK and in the US. Also occasionally known in English as ''ayaguasca'' (Spanish-derived), ''aioasca'' (Brazilian Portuguese-derived), or as ''yagé'', pronounced or . Etymologically, all forms but ''yagé'' descen ...
'' (which contains DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
), '' San Pedro'' (which contains mescaline
Mescaline or mescalin (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin.
Biological sou ...
), '' Psilocybe mushrooms'' (which contain psilocin/ psilocybin) and '' Tabernanthe iboga'' (which contains the unique psychedelic ibogaine) all have a long and extensive history of spiritual, shamanic
Shamanism is a religious practice that involves a practitioner (shaman) interacting with what they believe to be a spirit world through altered states of consciousness, such as trance. The goal of this is usually to direct spirits or spiritu ...
and traditional usage by indigenous peoples
Indigenous peoples are culturally distinct ethnic groups whose members are directly descended from the earliest known inhabitants of a particular geographic region and, to some extent, maintain the language and culture of those original people ...
in various world regions, particularly in Latin America
Latin America or
* french: Amérique Latine, link=no
* ht, Amerik Latin, link=no
* pt, América Latina, link=no, name=a, sometimes referred to as LatAm is a large cultural region in the Americas where Romance languages — languages derived f ...
but in the case of iboga, Gabon
Gabon (; ; snq, Ngabu), officially the Gabonese Republic (french: République gabonaise), is a country on the west coast of Central Africa. Located on the equator, it is bordered by Equatorial Guinea to the northwest, Cameroon to the north ...
, Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
.
Different countries have come to be associated with particular psychedelic entheogens, such as the entheogenic use of psilocybe mushrooms by the native Mazatec people of Oaxaca
Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...
, Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
.
Psychedelic therapy
Psychedelic therapy (or psychedelic-assisted therapy) is the proposed use of psychedelic drugs to treat mental disorder
A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitti ...
s. As of 2021, psychedelic drugs are controlled substances in most countries and psychedelic therapy is not legally available outside clinical trials, with some exceptions.
The procedure for psychedelic therapy differs from that of therapies
A therapy or medical treatment (often abbreviated tx, Tx, or Tx) is the attempted remediation of a health problem, usually following a medical diagnosis.
As a rule, each therapy has indications and contraindications. There are many different ...
using conventional psychiatric medications. While conventional medications are usually taken without supervision at least once daily, in contemporary psychedelic therapy the drug is administered in a single session (or sometimes up to three sessions) in a therapeutic context. The therapeutic team prepares the patient for the experience beforehand and helps them integrate insights from the drug experience afterwards. After ingesting the drug, the patient normally wears eyeshades and listens to music to facilitate focus on the psychedelic experience, with the therapeutic team interrupting only to provide reassurance if adverse effects such as anxiety or disorientation arise.
As of 2022, the body of high-quality evidence on psychedelic therapy remains relatively small and more, larger studies are needed to reliably show the effectiveness and safety of psychedelic therapy's various forms and applications. On the basis of favorable early results, ongoing research is examining proposed psychedelic therapies for conditions including major depressive disorder
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introdu ...
, and anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
and depression linked to terminal illness. The United States Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
has granted "breakthrough therapy" status, which expedites the assessment of promising drug therapies for potential approval, to psilocybin therapy for treatment-resistant depression and major depressive disorder.
Recreational
Recreational use of psychedelics is common. A US survey published in 2013 found that 13.4% of adults had used a psychedelic.
Microdosing
Psychedelic microdosing is the practice of using sub-threshold doses ( microdoses) of psychedelics in an attempt to improve creativity, boost physical energy level, emotional balance, increase performance on problems-solving tasks and to treat anxiety, depression and addiction. The practice of microdosing has become more widespread in the 21st century with more people claiming long-term benefits from the practice.
A 2022 study recognized signatures of psilocybin microdosing in natural language
In neuropsychology, linguistics, and philosophy of language, a natural language or ordinary language is any language that has evolved naturally in humans through use and repetition without conscious planning or premeditation. Natural languages ...
and concluded that low amount of psychedelics have potential for application, and ecological observation of microdosing schedules.
Pharmacology
While the method of action of psychedelics is not fully understood, they are known to show affinities for various 5-HT (serotonin) receptors in different ways and levels, and may be classified by their activity at different 5-HT sub-types, particularly 5-HT1A, 5-HT2A, and 5-HT2C. It is almost unanimously agreed that psychedelics produce their effect by acting as strong partial agonist
An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...
s at the 5-HT2A receptors. How this produces the psychedelic experience is unclear, but it is likely that it acts by increasing excitation in the cortex, possibly by specifically facilitating input from the thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, ...
, the major relay for sensory information input to the cortex. Additionally, researchers discovered that many psychedelics are potent psychoplastogen Psychoplastogens are a group of small molecule drugs that produce rapid and sustained effects on neuronal structure and function, intended to manifest therapeutic benefit after a single administration. Several existing psychoplastogens have been ...
s, compounds capable of promoting rapid and sustained neural plasticity.
Tryptamines
Tryptamine, along with other trace amine
Trace amines are an endogenous group of trace amine-associated receptor 1 (TAAR1) agonists – and hence, monoaminergic neuromodulators – that are structurally and metabolically related to classical monoamine neurotransmitters. Compared to the ...
s, is found in the central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all par ...
of mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s. It is hypothesized to play a role as a neuromodulator on classical monoamine neurotransmitters, such as dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...
, serotonin, and norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
(epinephrine
Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...
). Tryptamine acts as a non-selective serotonin receptor agonist to activate serotonin receptors, and a serotonin–norepinephrine–dopamine releasing agent (SNDRA) to release more monoamine neurotransmitter, with a preference for evoking serotonin and dopamine release
Release may refer to:
* Art release, the public distribution of an artistic production, such as a film, album, or song
* Legal release, a legal instrument
* News release, a communication directed at the news media
* Release (ISUP), a code to ident ...
over norepinephrine (epinephrine) release. Psychedelic tryptamines found in nature include psilocin, DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
, 5-MeO-DMT
5-MeO-DMT (5-methoxy-''N'',''N''-dimethyltryptamine) or O-methyl-bufotenin is a psychedelic of the tryptamine class. It is found in a wide variety of plant species, and also is secreted by the glands of at least one toad species, the Colorado Ri ...
, and tryptamines that have been synthesized in the laboratory include 4-HO-MET
4-HO-MET (4-hydroxy-''N''-methyl-''N''-ethyltryptamine, metocin, or methylcybin), is a lesser-known psychedelic drug. It is a structural− and functional analog of psilocin as well as the 4-hydroxyl analog of methylethyltryptamine (MET). 4-HO-M ...
, 4-HO-MiPT
4-HO-MiPT (miprocin, 4-hydroxy-''N''-methyl-''N''-isopropyltryptamine) is a synthetic substituted aromatic compound and a lesser-known psychedelic tryptamine. It is thought to be a serotonergic psychedelic, similar to magic mushrooms, LSD and ...
, and 5-MeO-DALT
5-MeO-DALT or ''N,N''- di allyl-5-methoxy tryptamine is a psychedelic tryptamine first synthesized by Alexander Shulgin.
Chemistry
The full name of the chemical is ''N''-allyl-''N''-indol-3-yl)ethyl group">ethyl] propene, prop-2-en-1- amine. It i ...
.
Phenethylamines
Phenethylamine
Phenethylamine (PEA) is an organic compound, natural monoamine alkaloid, and trace amine, which acts as a central nervous system stimulant in humans. In the brain, phenethylamine regulates monoamine neurotransmission by binding to trace amin ...
is also a trace amine
Trace amines are an endogenous group of trace amine-associated receptor 1 (TAAR1) agonists – and hence, monoaminergic neuromodulators – that are structurally and metabolically related to classical monoamine neurotransmitters. Compared to the ...
but to a lesser extent acts as a neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Neuro ...
in the human central nervous system (CNS). Phenethylamine instead regulates monoamine neurotransmission by binding to trace amine-associated receptor 1 (TAAR1), which plays a significant role in regulating neurotransmission in dopamine, norepinephrine, and serotonin neurons in the CNS and inhibiting vesicular monoamine transporter 2
The solute carrier family 18 member 2 (SLC18A2) also known as vesicular monoamine transporter 2 (VMAT2) is a protein that in humans is encoded by the ''SLC18A2'' gene. SLC18A2 is an integral membrane protein that transports monoamines—particul ...
(VMAT2) in monoamine neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. N ...
s. When VMAT2 is inhibited monoamine neurotransmitters such as dopamine cannot be released into the synapse via typical release mechanisms. Mescaline is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class.
Lysergamides
Amide
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it is ...
s of lysergic acid
Lysergic acid, also known as -lysergic acid and (+)-lysergic acid, is a precursor for a wide range of ergoline alkaloids that are produced by the ergot fungus and found in the seeds of '' Turbina corymbosa'' (ololiuhqui), '' Argyreia nervosa'' ...
are collectively known as lysergamides, and include a number of compounds with potent agonist and/or antagonist activity at various serotonin and dopamine receptors. Lysergamides contain both Tryptamine and Phenethylamine structure although it is class as a complex Tryptamine. LSD (Lysergic Acid Diethylamide) is one of many lysergamides. A wide range of lysergamides have emerged in recent years, inspired by existing scientific literature. Others, have appeared from chemical research. 1P-LSD
1P-LSD or 1-propionyl-lysergic acid diethylamide is a psychedelic drug of the lysergamide class that is a derivative and functional analogue of LSD and a homologue of ALD-52. It has been sold online as a designer drug since 2015. It modifies t ...
is a derivative
In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. F ...
and functional analogue of LSD and a homologue of ALD-52. It modifies the LSD molecule by adding a propionyl group to the nitrogen molecule of LSD's indole.
Psychedelic experiences
Although several attempts have been made, starting in the 19th and 20th centuries, to define common phenomenological
Phenomenology may refer to:
Art
* Phenomenology (architecture), based on the experience of building materials and their sensory properties
Philosophy
* Phenomenology (philosophy), a branch of philosophy which studies subjective experiences and a ...
structures of the effects produced by classic psychedelics, a universally accepted taxonomy does not yet exist. At lower doses, features of psychedelic experiences include sensory alterations, such as the warping of surfaces, shape suggestibility, and color variations. Users often report intense colors that they have not previously experienced, and repetitive geometric shapes are common. Higher doses often cause intense and fundamental alterations of sensory perception, such as synesthesia
Synesthesia (American English) or synaesthesia (British English) is a perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second sensory or cognitive pathway. People who re ...
or the experience of additional spatial or temporal dimensions.
Classic psychedelics are considered to be those found in nature like psilocybin, DMT
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
, mescaline
Mescaline or mescalin (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin.
Biological sou ...
, and LSD which is derived from naturally occurring ergotamine, and non-classic psychedelics are considered to be newer analogs and derivatives of pharmacophore lysergamides, tryptamine, and phenethylamine
Phenethylamine (PEA) is an organic compound, natural monoamine alkaloid, and trace amine, which acts as a central nervous system stimulant in humans. In the brain, phenethylamine regulates monoamine neurotransmission by binding to trace amin ...
structures like 2C-B
2C-B (4-Bromo-2,5-dimethoxyphenethylamine) is a psychedelic drug of the 2C family. It was first synthesized by Alexander Shulgin in 1974. In Shulgin's book '' PiHKAL'', the dosage range is listed as 12–24 mg. As a recreational drug, 2C-B is so ...
. Many of these psychedelics cause remarkably similar effects, despite their different chemical structure. However, many users report that the three major families have subjectively different qualities in the "feel" of the experience, which are difficult to describe. Some compounds, such as 2C-B, have extremely tight "dose curves", meaning the difference in dose between a non-event and an overwhelming disconnection from reality can be very slight. There can also be very substantial differences between the drugs; for instance, 5-MeO-DMT
5-MeO-DMT (5-methoxy-''N'',''N''-dimethyltryptamine) or O-methyl-bufotenin is a psychedelic of the tryptamine class. It is found in a wide variety of plant species, and also is secreted by the glands of at least one toad species, the Colorado Ri ...
rarely produces the visual effects typical of other psychedelics. Tryptamines are well documented to cause classic psychedelic states, such as increased empathy, visual distorsions (drifting, morphing, breathing, melting of various surfaces and objects), auditory hallucinations, ego dissolution or ego death with high enough dose, mystical and spiritual experiences, closed eye hallucinations and complete detachment from reality with a high enough dose.
Potential adverse effects
Despite the contrary perception of much of the public, psychedelic drugs are not addictive and are physiologically safe. As of 2016, there have been no known deaths due to overdose of LSD, psilocybin, or mescaline.
Risks do exist during an unsupervised psychedelic experience, however; Ira Byock wrote in 2018 in the ''Journal of Palliative Medicine
The ''Journal of Palliative Medicine (JPM)'' is the journal of both the Center to Advance Palliative Care and the Hospice and Palliative Nurses Association. JPM covers aspects of end of life medical care.
Anesthesiology and palliative medi ...
'' that psilocybin is safe when administered to a properly screened patient and supervised by a qualified professional with appropriate set and setting. However, he called for an "abundance of caution" because in the absence of these conditions a range of negative reactions is possible, including "fear, a prolonged sense of dread, or full panic." He notes that driving or even walking in public can be dangerous during a psychedelic experience because of impaired hand-eye coordination and fine motor control
Fine motor skill (or dexterity) is the coordination of small muscles in movement with the eyes, hands and fingers. The complex levels of manual dexterity that humans exhibit can be related to the nervous system. Fine motor skills aid in the growt ...
. In some cases, individuals taking psychedelics have performed dangerous or fatal acts because they believed they possessed superhuman powers.
The usage of most psychedelics entails some risk of eliciting flashbacks of the drug experience even after the effects have worn off, albeit rarely. HPPD or other after-effects may also occur. Psilocybin-induced states of mind share features with states experienced in psychosis
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavior ...
, and while a causal relationship between psilocybin and the onset of psychosis has not been established as of 2011, researchers have called for investigation of the relationship. Many of the persistent negative perceptions of psychological risks are unsupported by the currently available scientific evidence, with the majority of reported adverse effects not being observed in a regulated and/or medical context. A population study Population study is an interdisciplinary field of scientific study that uses various statistical methods and models to analyse, determine, address, and predict population challenges and trends from data collected through various data collection m ...
on associations between psychedelic use and mental illness published in 2013 found no evidence that psychedelic use was associated with increased prevalence of any mental illness.
Potential therapeutic effects
Psychedelic substances which may have therapeutic uses include psilocybin, LSD, and mescaline. During the 1950s and 1960s, lack of informed consent
Informed consent is a principle in medical ethics and medical law, that a patient must have sufficient information and understanding before making decisions about their medical care. Pertinent information may include risks and benefits of treatme ...
in some scientific trials on psychedelics led to significant, long-lasting harm to some participants. Since then, research regarding the effectiveness of psychedelic therapy has been conducted under strict ethical guidelines, with fully informed consent and a pre-screening to avoid people with psychosis
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavior ...
taking part. Although the history behind these substances has hindered research into their potential medicinal value, scientists are now able to conduct studies and renew research that was halted in the 1970s. Some research has shown that these substances have helped people with such mental disorders as obsessive-compulsive disorder (OCD), post-traumatic stress disorder
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on ...
(PTSD), alcoholism
Alcoholism is, broadly, any drinking of alcohol (drug), alcohol that results in significant Mental health, mental or physical health problems. Because there is disagreement on the definition of the word ''alcoholism'', it is not a recognize ...
, depression, and cluster headaches
Cluster headache (CH) is a neurological disorder characterized by recurrent severe headaches on one side of the head, typically around the eye(s). There is often accompanying eye watering, nasal congestion, or swelling around the eye on the af ...
.
It has long been known that psychedelics promote neurite growth and neuroplasticity and are potent psychoplastogen Psychoplastogens are a group of small molecule drugs that produce rapid and sustained effects on neuronal structure and function, intended to manifest therapeutic benefit after a single administration. Several existing psychoplastogens have been ...
s. There is evidence that psychedelics induce molecular and cellular adaptations related to neuroplasticity and that these could potentially underlie therapeutic benefits. Psychedelics have also been shown to have potent anti-inflammatory activity and therapeutic effects in animal models of inflammatory diseases including asthma, and cardiovascular disease and diabetes.
Surrounding culture
Psychedelic culture includes manifestations such as psychedelic music
Psychedelic music (sometimes called psychedelia) is a wide range of popular music styles and genres influenced by 1960s psychedelia, a subculture of people who used psychedelic drugs such as LSD, psilocybin mushrooms, mescaline, and cannabis to ...
, psychedelic art, psychedelic literature, psychedelic film
Psychedelic film is a film genre characterized by the influence of psychedelia and the experiences of psychedelic drugs. Psychedelic films typically contain visual distortion and experimental narratives, often emphasizing psychedelic imagery. The ...
, and psychedelic festivals
A festival is an event ordinarily celebrated by a community and centering on some characteristic aspect or aspects of that community and its religion or cultures. It is often marked as a local or national holiday, mela, or eid. A festival co ...
.[St John, Graham]
"Neotrance and the Psychedelic Festival."
''Dancecult: Journal of Electronic Dance Music Culture,'' 1(1) (2009). Examples of psychedelic music would be rock bands like the Grateful Dead
The Grateful Dead was an American rock music, rock band formed in 1965 in Palo Alto, California. The band is known for its eclectic style, which fused elements of rock, Folk music, folk, country music, country, jazz, bluegrass music, bluegrass, ...
and Jefferson Airplane
Jefferson Airplane was an American rock band based in San Francisco, California, that became one of the pioneering bands of psychedelic rock. Formed in 1965, the group defined the San Francisco Sound and was the first from the Bay Area to ac ...
. Many psychedelic bands and elements of the psychedelic subculture originated in San Francisco
San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of Ca ...
during the mid to late 1960s.
Legal status
Many psychedelics are classified under Schedule I of the United Nations Convention on Psychotropic Substances
The Convention on Psychotropic Substances of 1971 is a United Nations treaty designed to control psychoactive drugs such as #Amphetamine-type stimulants, amphetamine-type stimulants, barbiturates, benzodiazepines, and Psychedelic drug, psychede ...
of 1971 as drugs with the greatest potential to cause harm and no acceptable medical uses. In addition, many countries have analogue laws; for example, in the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
, the Federal Analogue Act of 1986 automatically forbids any drugs sharing similar chemical structures or chemical formulas to illicit or prohibited substances if sold for human consumption.
U.S. states such as Oregon and Colorado have also instituted decriminalization and legalization measures of psychedelics and states like New Hampshire and others are attempting to do the same.
See also
* Aztec use of entheogens
* Bwiti
* Cognitive liberty
* Concord Prison Experiment
The Concord Prison Experiment, conducted from 1961 to 1963, was designed to evaluate whether the experiences produced by the psychoactive drug psilocybin, derived from psilocybin mushrooms, combined with psychotherapy, could inspire prisoners to l ...
* Designer Drugs
A designer drug is a structural or functional analog of a controlled substance that has been designed to mimic the pharmacological effects of the original drug, while avoiding classification as illegal and/or detection in standard drug tests. Des ...
* Dissociative drug
* Drug harmfulness
Recreational drug use indicates the use of one or more psychoactive drugs to induce an altered state of consciousness either for pleasure or for some other casual purpose or pastime by modifying the perceptions and emotions of the user. When a ...
* Entheogenic drugs and the archaeological record
Entheogenic drugs have been used by various groups for thousands of years. There are numerous
historical reports as well as modern, contemporary reports of indigenous groups using entheogens, chemical substances used in a religious, shamanic, or s ...
* Entheogenics and the Maya
The consumption of hallucinogenic plants as entheogens goes back to thousands of years. Psychoactive plants contain hallucinogenic particles that provoke an altered state of consciousness, which are known to have been used during spiritual ritua ...
* Hallucinogenic fish
* Hallucinogenic plants in Chinese herbals For over two millennia, texts in Chinese herbology and traditional Chinese medicine have recorded medicinal plants that are also hallucinogens and psychedelics. Some are familiar psychoactive plants in Western herbal medicine (e.g., , i.e. ''Hyoscya ...
* ''Hamilton's Pharmacopeia
''Hamilton's Pharmacopeia'' is an American docuseries, which premiered on Viceland on October 26, 2016. The show follows Hamilton Morris as he explores the history, chemistry and social impact of psychoactive substances. It chronicles Morris' ...
''
* History of lysergic acid diethylamide
The psychedelic drug (or entheogen) lysergic acid diethylamide (LSD) was first synthesized on November 16, 1938, by the Swiss chemist Albert Hofmann in the Sandoz (now Novartis) laboratories in Basel, Switzerland.Albert Hofmann; translated from ...
* Ibogaine
* List of psychedelic plants
This is a list of plant species that, when consumed by humans, are known or suspected to produce psychoactive effects: changes in nervous system function that alter perception, mood, consciousness, cognition or behavior. Many of these plants a ...
* Marsh Chapel Experiment
* Morning glory
* Mystical psychosis
Mystical psychosis is a term coined by Arthur J. Deikman in the early 1970s to characterize first-person accounts of psychotic experiences that are strikingly similar to reports of mystical experiences. According to Deikman, and authors from a nu ...
* '' PiHKAL''
*
* Serotonergic cell groups
* Serotonin syndrome
* '' Tabernanthe iboga''
* ''TiHKAL
''TIHKAL: The Continuation'' is a 1997 book written by Alexander Shulgin and Ann Shulgin about a family of psychoactive drugs known as tryptamines. A sequel to '' PIHKAL: A Chemical Love Story'', ''TIHKAL'' is an acronym that stands for "Tryp ...
''
* Research chemical
Research chemicals are chemical substances used by scientists for medical and scientific research purposes. One characteristic of a research chemical is that it is for laboratory research use only; a research chemical is not intended for human o ...
* List of psychedelic drugs
The following is a list of psychedelic drugs of various chemical classes, including both naturally occurring and synthetic compounds. Serotonergic psychedelics are usually considered the "classical" psychedelics, whereas the other classes are oft ...
* List of designer drugs
Categories
Notes
References
Further reading
*
*
*
*
*
*
* Winstock, Ar; Timmerman, C; Davies, E; Maier, Lj; Zhuparris, A; Ferris, Ja; Barratt, Mj; Kuypers, Kpc (2021).
Global Drug Survey (GDS) 2020 Psychedelics Key Findings Report
'.
External links
Psychedelic Timeline
by Tom Frame. Psychedelic Times.
* PsychonautWiki.orgbr>a community-driven online encyclopedia
{{Serotonin receptor modulators
Drug classes defined by psychological effects
5-HT2A agonists
Hallucinations