Lysergic acid diethylamide, commonly known as LSD (from German Lysergsäure-diethylamid), and known colloquially as acid or lucy, is a potent psychedelic drug.[12] Effects typically include intensified thoughts, emotions, and sensory perception.[13] At sufficiently high dosages, LSD manifests primarily mental, visual, and auditory hallucinations.[14][15] Dilated pupils, increased blood pressure, and increased body temperature are typical.[16]
Effects typically begin within half an hour and can last for up to 20 hours (although on average, experiences last 8–12 hours).[16][17] LSD is also capable of causing mystical experiences and ego dissolution.[15][18] It is used mainly as a recreational drug or for spiritual reasons.[16][19] LSD is both the prototypical psychedelic and one of the "classical" psychedelics, being the psychedelic with the greatest scientific and cultural significance.[12] LSD is synthesized as a solid compound, typically in the form of a powder or a crystalline material. This solid LSD is then dissolved in a liquid solvent, such as ethanol or distilled water, to create a solution. The liquid serves as a carrier for the LSD, allowing for accurate dosage and administration onto small pieces of blotter paper called tabs. LSD is typically either swallowed or held under the tongue.[13] In pure form, LSD is clear or white in color, has no smell, and is crystalline.[13] It breaks down with exposure to ultraviolet light.[16]
LSD is structurally related to substituted tryptamines, a class of compounds that includes psilocybin, the active compound found in psychedelic mushrooms. Thus, LSD shares some mechanisms of action and psychedelic effects with psilocybin and other tryptamines.[22][23][24]
The effects of LSD are thought to stem primarily from it being an agonist at the 5-HT2Aserotonin receptor. While exactly how LSD exerts its effects by agonism at this receptor is not fully understood, corresponding increased glutamatergic neurotransmission and reduced default mode network activity are thought to be key mechanisms of action.[7][12][25][26][27] LSD also binds to dopamineD1 and D2 receptors, which is thought to contribute to reports of LSD being more stimulating than compounds such as psilocybin.[28][29]
Swiss chemist Albert Hofmann first synthesized LSD in 1938 from lysergic acid, a chemical derived from the hydrolysis of ergotamine, an alkaloid found in ergot, a fungus that infects grain.[16][20] LSD was the 25th of various lysergamides Hofmann synthesized from lysergic acid while trying to develop a new analeptic, hence the alternate name LSD-25. Hofmann discovered its effects in humans in 1943, after unintentionally ingesting an unknown amount, possibly absorbing it through his skin.[30][31][32] LSD was subject to exceptional interest within the field of psychiatry in the 1950s and early 1960s, with Sandoz distributing LSD to researchers under the trademark name Delysid in an attempt to find a marketable use for it.[31]
In the 1960s, LSD and other psychedelics were adopted by, and became synonymous with, the counterculture movement due to their perceived ability to expand consciousness. This resulted in LSD being viewed as a cultural threat to American values and the Vietnam war effort, and it was designated as a Schedule I (illegal for medical as well as recreational use) substance in 1968.[36] It was listed as a Schedule 1 controlled substance by the United Nations in 1971 and currently has no approved medical uses.[16] As of 2017[update], about 10% of people in the United States have used LSD at some point in their lives, while 0.7% have used it in the last year.[37] It was most popular in the 1960s to 1980s.[16] The use of LSD among US adults increased 56.4% from 2015 to 2018.[38]
^Halpern JH, Suzuki J, Huertas PE, Passie T (June 7, 2014). "Hallucinogen Abuse and Dependence". In Price LH, Stolerman IP (eds.). Encyclopedia of Psychopharmacology A Springer Live Reference. Heidelberg, Germany: Springer-Verlag Berlin Heidelberg. pp. 1–5. doi:10.1007/978-3-642-27772-6_43-2. ISBN978-3-642-27772-6. Hallucinogen abuse and dependence are known complications resulting from ... LSD and psilocybin. Users do not experience withdrawal symptoms, but the general criteria for substance abuse and dependence otherwise apply. Dependence is estimated in approximately 2 % of recent-onset users
^Cite error: The named reference NHM-MDMA was invoked but never defined (see the help page).
^ abcdeCite error: The named reference Dol2015 was invoked but never defined (see the help page).
^ abc"What are hallucinogens?". National Institute of Drug Abuse. January 2016. Archived from the original on April 17, 2016. Retrieved April 24, 2016.
^Leptourgos P, Fortier-Davy M, Carhart-Harris R, Corlett PR, Dupuis D, Halberstadt AL, et al. (December 2020). "Hallucinations Under Psychedelics and in the Schizophrenia Spectrum: An Interdisciplinary and Multiscale Comparison". Schizophrenia Bulletin. 46 (6): 1396–1408. doi:10.1093/schbul/sbaa117. PMC7707069. PMID32944778. Thalamocortical connectivity was found altered in psychedelic states. Specifically, LSD was found to selectively increase effective connectivity from the thalamus to certain DMN areas, while other connections are attenuated. Furthermore, increased thalamic connectivity with the right fusiform gyrus and the anterior insula correlated with visual and auditory hallucinations (AH), respectively.
^Halpern JH, Lerner AG, Passie T (2018). A Review of Hallucinogen Persisting Perception Disorder (HPPD) and an Exploratory Study of Subjects Claiming Symptoms of HPPD. Current Topics in Behavioral Neurosciences. Vol. 36. pp. 333–360. doi:10.1007/7854_2016_457. ISBN978-3-662-55878-2. PMID27822679.
^Wong S, Yu AY, Fabiano N, Finkelstein O, Pasricha A, Jones BDM, et al. (August 2023). "Beyond Psilocybin: Reviewing the Therapeutic Potential of Other Serotonergic Psychedelics in Mental and Substance Use Disorders". Journal of Psychoactive Drugs: 1–17. doi:10.1080/02791072.2023.2251133. PMID37615379. S2CID261098164.
^Cite error: The named reference pmid24309097 was invoked but never defined (see the help page).
^Cite error: The named reference nichols_closes_shop was invoked but never defined (see the help page).
^Hofmann A (2009). LSD, my problem child: reflections on sacred drugs, mysticism, and science (4th ed.). Santa Cruz, CA: Multidisciplinary Association for Psychedelic Studies. ISBN978-0-9798622-2-9. OCLC610059315.
^ abcdefLee MA, Shlain B (1992). Acid dreams: the complete social history of LSD: the CIA, the Sixties, and beyond. New York: Grove Weidenfeld. ISBN0-8021-3062-3. OCLC25281992.
^Chwelos N, Blewett DB, Smith CM, Hoffer A (September 1959). "Use of d-lysergic acid diethylamide in the treatment of alcoholism". Quarterly Journal of Studies on Alcohol. 20 (3): 577–590. doi:10.15288/qjsa.1959.20.577. PMID13810249.
^Krebs TS, Johansen PØ (July 2012). "Lysergic acid diethylamide (LSD) for alcoholism: meta-analysis of randomized controlled trials". Journal of Psychopharmacology. 26 (7): 994–1002. doi:10.1177/0269881112439253. PMID22406913. S2CID10677273.
^United States Congress House Committee on Interstate and Foreign Commerce Subcommittee on Public Health and Welfare (1968). Increased Controls Over Hallucinogens and Other Dangerous Drugs. U.S. Government Printing Office. Archived from the original on July 13, 2020. Retrieved August 3, 2021.
^National Institute on Drug Abuse. "Hallucinogens". Archived from the original on June 3, 2020. Retrieved July 14, 2018.