Early history
- See also: Entheogenic drugs and the archaeological record, Aztec use of entheogens, and Entheogenics and the Maya
Psychedelics occurring in plants, fungi, and animals have been used by indigenous peoples throughout the world for thousands of years. These psychedelics and their sources include psilocybin and psilocin in psilocybin-containing mushrooms (teonanacatl), dimethyltryptamine (DMT) in ayahuasca (a combination typically of Psychotria viridis and Banisteriopsis caapi), bufotenin in Anadenanthera trees, 5-MeO-DMT in the Colorado River Toad, mescaline in peyote (peyotl) and San Pedro cacti, and ergine and isoergine in morning glories (ololiuqui, tlitliltzin) and ergot, among others. The kykeon of the Eleusinian Mysteries in Ancient Greece might have been a psychedelic, for instance ergot or psilocybin-containing mushrooms. The earliest archeological evidence of the use of psychedelic plants and fungi by humans dates back roughly 10,000years.
Western characterization
- See also: History of entheogenic drugs and History of LSD
Psychedelics were discovered by the Western world and the scientific community relatively late. The use of hallucinogenic snuffs by indigenous South American people was first observed by Western explorers like Christopher Columbus as early as 1496. The first written description of an observed psychedelic experience, with cohoba, was published by Ramon Pane in 1511. Spanish explorers observed the use of psilocybin-containing mushrooms (teonanacatl) in Mexico as early as 1519 with the arrival of Hernán Cortés. Spanish ethnographer Bernardino de Sahagún traveled to Mexico in 1529 and described the use of these mushrooms in his books. The botanists Richard Spruce and Alfred Russel Wallace observed and described the use of ayahuasca in the Amazon in the 1850s.
The phenethylamine psychedelic mescaline
Mescaline is sometimes described as the "first psychedelic", as it was the first to be discovered and characterized by the Western world. American physician John Raleigh Briggs, living in Texas, learned of peyote from Native Americans and Mexicans, who told him that it produced "beautiful visions" and made them journey into the "spirit world". He obtained mescal buttons from Mexico and published a journal article about trying a very low dose of them in May 1887. This article is said to have brought peyote into North American pharmacology. Briggs described the physiological effects of his experience, such as increased heart rate, and of experiencing "intoxication". The article was read by George Davis, of Parke, Davis and Company, who then obtained the buttons from Briggs in June 1887. Parke-Davis attempted to market peyote as a cardiac stimulant and for other uses, but met with little success. The German pharmacologist Louis Lewin obtained mescal buttons from Parke-Davis during a trip to the United States in 1887 and began studying them and sharing his findings.
The first known published description of a hallucinogenic peyote experience was by American neurologist Silas Weir Mitchell in December 1896. After reading Mitchell's article, others, including psychologist and sexologist Havelock Ellis, American psychologist William James, and German pharmacologist, chemist, and Lewin rival Arthur Heffter, among others, tried peyote and described their experiences. Heffter isolated and ingested mescaline from peyote, experiencing psychedelic effects with the pure compound, in 1897, and published his findings in 1898.
Austrian chemist Ernst Späth synthesized mescaline for the first time in 1919. The German pharmaceutical company Merck then began distributing pharmaceutical mescaline in 1920. The German psychiatrist Kurt Beringer, a student of Lewin and an acquaintance of Hermann Hesse and Carl Jung, became the father of psychedelic psychiatry and conducted experiments with mescaline in more than 60people starting in 1921. He published his monograph on the subject, Der Meskalinrausch (Mescaline Intoxication), in 1927. German–American psychologist Heinrich Klüver published his monograph, Mescal: The Divine Plant and Its Psychological Effects, in English in 1928. He is said to have been the first to attempt to provide a phenomenological description of the psychedelic experience.
Tryptamine and lysergamide psychedelics
Austrian anthropologist and ethnobotanist Blas Pablo Reko, traveling through Central and South America, wrote of the use of teonanacatl by native Mexican people in Oaxaca in 1919. Reko subsequently sent samples of teonanacatl (Psilocybe mexicana) as well as Ipomoea violacea (morning glory) seeds to Swedish anthropologist Henry Wassén in 1937. Reko had obtained the mushroom sample from Austrian engineer Robert Weitlaner who was working in Mexico. Eventually, Wassén forwarded Reko and Weitlaner's mushroom sample to Harvard University, where the mushrooms came to the attention of American ethnobotanist Richard Evans Schultes. However, they had decomposed so badly that they could not be identified. Prior to Wassén obtaining specimens around 1936, the existence of teonanacatl was very controversial and was debated and even denied by some. In 1938, a small group of Westerners, which included Weitlaner's daughter and American anthropologist Jean Basset Johnson, attended a mushroom ceremony. They were the first Westerners known to do so and described the event. Schultes published reviews of teonanacatl being a hallucinogenic mushroom in the late 1930s. Schultes obtained specimens of three of the hallucinogenic mushrooms used in ceremonies, including Psilocybe caerulescens, Panaeolus campanulatus, and Stropharia cubensis, but further investigations of the mushrooms were interrupted by World War II.
Ergine (lysergic acid amide; LSA) and isoergine (isolysergic acid amide; iso-LSA) were first identified from hydrolysis of ergot alkaloids in 1932 and 1936, respectively. In 1938, Swiss chemist Albert Hofmann, working at Sandoz Laboratories, synthesized lysergic acid diethylamide (LSD), a synthetic derivative of ergine, while developing new oxytocic drugs derived from ergot. LSD was not further investigated and was placed in storage for 5years. In 1943 however, Hofmann worked with LSD again and accidentally discovered its hallucinogenic effects when minute amounts of the potent psychedelic absorbed through his skin. His subsequent self-experiment with LSD three days later on April 19 is the psychedelic holiday Bicycle Day. Hofmann and his colleague, psychiatrist Werner Stoll, first described LSD in 1943 and first described its psychedelic effects in 1947. LSD began being distributed by Sandoz Laboratories for research purposes under the brand name Delysid in 1949.
Schultes described the indigenous and shamanic use of dimethyltryptamine (DMT)-containing psychedelic plants in 1954 and also described the use of hallucinogenic morning glories in the 1950s. The psychedelic effects of synthesized DMT were described by Hungarian chemist and psychiatrist Stephen Szára in 1956. Osmond described the hallucinogenic and other effects of morning glory seeds in clinical studies in 1955. Hofmann identified and described ergine and isoergine as the active constituents of morning glory seeds in 1960. Their hallucinogenic effects were first described by Hofmann in 1963.
In 1952, couple and amateur ethnomycologists R. Gordon Wasson and Valentina Wasson learned of the ritual use of hallucinogenic mushrooms in the 16th century in Mexico from the published work of Schultes. They made several trips to Mexico in search of the mushrooms. In mid-1955, the Wassons participated in a mushroom ceremony with Mazatec curandera Maria Sabina in Huautla de Jiménez, Oaxaca, Mexico. Gordon Wasson published his experience in an article for Life magazine titled "Seeking the Magic Mushroom" in 1957, while Valentina Wasson published her experience as "I Ate the Sacred Mushroom" in This Week magazine the same year. Later in 1957, a second expedition was made by the Wassons to Mexico with French mycologist Roger Heim. Heim identified several of the mushrooms as belonging to the genus Psilocybe. They collected samples of the mushrooms and Heim sent a sample to Hofmann. Hofmann identified psilocybin as the active constituent in 1958 and developed a chemical synthesis for it. Sandoz Pharmaceuticals began distributing tablets of psilocybin under the brand name Indocybin in 1960.
French scientists Césaire Phisalix and Gabriel Bertrand isolated bufotenin from Bufo toads in 1893 and named it. The compound was first isolated to purity by Austrian chemist Hans Handovsky in 1920. Clinical studies assessed the effects of bufotenin and were published starting in 1956. However, the findings of these studies were conflicting, and bufotenin developed a long-standing reputation of being inactive and toxic. American ethnobotanist Jonathan Ott and colleagues subsequently showed in 2001 that bufotenin is in fact a psychedelic and does not necessarily produce major adverse effects, although marked nausea and vomiting are prominent. The related psychedelic 5-MeO-DMT was first synthesized by Japanese chemists Toshio Hoshino and Kenya Shimodaira in 1935. It was later isolated from Dictyoloma incanescens in 1959. Subsequently, 5-MeO-DMT was isolated from numerous other plants and fungi. The compound was isolated from the skin of toads, specifically the Colorado River toad (Incilius alvarius, formerly Bufo alvarius), by Italian chemist and pharmacologist Vittorio Erspamer in 1967. A 1984 pamphlet by Albert Most (real name Ken Nelson), titled Bufo Alvarius: the Psychedelic Toad of the Sonoran Desert, described how to obtain and use Colorado River toad secretions as a psychedelic drug, and this started its recreational use.
Mid-20th-century research, popularization, and prohibition
- See also: Psychedelic era and Counterculture of the 1960s §Marijuana, LSD, and other recreational drugs
Extensive clinical research on almost exclusively LSD, mescaline, and psilocybin was conducted in the 1950s and 1960s. However, the amount of research done on psilocybin was nowhere near that of LSD. Psychedelics like LSD started to become more visible in the mainstream sphere in the 1950s. English writer Aldous Huxley tried mescaline, which he had obtained from English psychiatrist Humphry Osmond, in 1953, and described its effects in his 1954 book The Doors of Perception. British politician Christopher Mayhew tried mescaline in 1955 and this was reported on in the media. Osmond, in correspondence with Huxley, coined the term "psychedelic", meaning "mind-manifesting", in 1956.
Psychedelics became widely recreationally used by the public, for instance by the hippies, during the counterculture of the 1960s. Harvard psychologists Timothy Leary and Richard Alpert began studying LSD and psilocybin in the early 1960s and ended up being fired from the university in 1963. Sandoz Laboratories ceased distribution of Delysid in 1965. Psychedelics became controlled substances in the United States and internationally in the 1960s and 1970s. By the end of the 1960s, psychedelic clinical research throughout the world had largely ceased.
Besides public research, it was eventually learned that the United States government had also conducted research into psychedelics, as possible mind-control and truth-serum drugs, in the 1940s through the 1970s, for instance Project MKUltra by the Central Intelligence Agency (CIA) and the Edgewood Arsenal research by the U.S. Army.
Creation of other synthetic psychedelics
The synthetic mescaline analogue 2,6-dibromomescaline was described by Arthur Heffter in 1901, although he is not known to have tested it and its psychedelic effects weren't reported until much later. The psychedelic effects of 3,4-methylenedioxyamphetamine (MDA), a synthetic analogue of mescaline that had been derived from amphetamine in 1910, were discovered by American chemist and pharmacologist Gordon Alles in 1930, but weren't subsequently published until 1959. 3,4,5-Trimethoxyamphetamine (TMA), another synthetic mescaline analogue, was first described in 1947 and its psychedelic effects were described in 1955. 2,4,5-Trimethoxyphenethylamine (2C-O), a synthetic positional isomer of mescaline, was synthesized and claimed to be psychedelic similarly to mescaline in 1931, but later trials found it to be inactive. Various synthetic tryptamine psychedelics, such as diethyltryptamine (DET), 4-PO-DET (CEY-19), and 4-HO-DET (CZ-74), were developed in the late 1950s. In addition, the synthetic α-alkyltryptamine analogues α-methyltryptamine (AMT; Indopan) and α-ethyltryptamine (AET; Monase), which are psychedelics and/or entactogens, were marketed and clinically used at non-hallucinogenic doses as antidepressants in the early 1960s, but were quickly withdrawn due to physical toxicity. Numerous synthetic psychedelic tryptamines were known by the mid-1970s.
Alexander Shulgin, an American chemist working at Dow Chemical Company, tried mescaline by 1960. This experience has been described as "the most consequential mescaline trip of the sixties", as it caused Shulgin to redirect his focus and life's work to psychedelic chemistry. Starting in the 1960s, Shulgin synthesized and gradually described hundreds of novel synthetic psychedelics as well as entactogens in scientific publications and published books such as PiHKAL (1991) and TiHKAL (1997). Notable major examples of these drugs have included the DOx psychedelic DOM, the 2C psychedelic 2C-B, and the MDxx entactogen MDMA, among others. However, MDMA was not an original creation of Shulgin's but had previously been first synthesized in 1912 and had surfaced as a recreational drug related to MDA by the mid- to late-1960s. Instead, Shulgin had merely served to help popularize and spread awareness about MDMA and its unique effects.
MDMA became outlawed in the mid-1980s. In response to this, the Multidisciplinary Association for Psychedelic Studies (MAPS) was founded by Rick Doblin in 1986 and began efforts to develop MDMA and other psychedelics as medicines. American chemist David E. Nichols has developed numerous novel psychedelics and entactogens from the 1970s to present. Swiss chemist Daniel Trachsel, sometimes referred to as the "German Shulgin", has also developed and published numerous novel psychedelics as well as entactogens since the 1990s.
NBOMe psychedelics such as 25I-NBOMe, derived from structural modification of 2C psychedelics, were first described by Ralf Heim and colleagues by 2000. The NBOMe drugs were subsequently encountered as novel recreational drugs by 2010, and by 2012 had eclipsed other psychedelics like LSD and psilocybin-containing mushrooms in popularity, at least for a time.
Psychedelics, serotonin, and their actions
Serotonin, also known as 5-hydroxytryptamine (5-HT) and originally called enteramine, was discovered by Vittorio Erspamer in the 1930s and its structural identity was fully characterized in the late 1940s and early 1950s. Serotonin was discovered in the brain by Betty Twarog and Irvine Page in 1953. It was quickly noticed that LSD contains the serotonin-like tryptamine scaffold within its chemical structure. Shortly thereafter, it was found that LSD showed serotonin-like effects and could antagonize serotonin in certain assays. Studies in the 1960s and 1970s showed that various serotonin antagonists could block the behavioral effects of psychedelics in animals. It was first proposed that LSD may be acting as an agonist of serotonin receptors by N. E. Andén and colleagues in 1968. The serotonin receptors, including the serotonin 5-HT2 receptors, were identified by the late 1970s. Mediation of the hallucinogenic effects of psychedelics specifically by serotonin 5-HT2 receptor agonism was proposed by Richard Glennon and other researchers by the early 1980s. The human serotonin 5-HT2A receptor was first cloned in 1990. The hallucinogenic effects of psilocybin in humans were shown to be blocked by the selective serotonin 5-HT2A receptor antagonist ketanserin by Franz Vollenweider and colleagues in 1998, solidifying theoretical notions that agonism of the serotonin 5-HT2A receptor mediates the hallucinogenic effects of serotonergic psychedelics.
Psychedelic renaissance
- See also: List of investigational hallucinogens and entactogens
Since the prohibition of the 1960s and 1970s, clinical research into psychedelics started to resume by the 1990s, for instance the studies of DMT by Rick Strassman, and they have once again started to be developed as pharmaceutical drugs for potential medical use. A so-called "psychedelic renaissance", in which interest in psychedelics has resurged, began in the late 2010s and early 2020s. Michael Pollan's 2018 book How to Change Your Mind, which was also adapted into a Netflix series in 2022, was especially impactful in terms of increasing mainstream awareness and interest in psychedelics. More than 100clinical trials of four major psychedelics, including psilocybin, LSD, ayahuasca, and MDMA, were identified as being underway in 2024.