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Scientific Name(s): Lophophora williamsii (Lem. ex Salm-Dyck) J.M. Coult.
Common Name(s): Anhalonium, Mescaline, Peyote, Peyotl, Peytote, Ubatama

Medically reviewed by Last updated on Aug 22, 2023.

Clinical Overview


Clinical studies of peyote are lacking. CNS effects, including hallucinations, have been described. Peyote may have immune-related activity; however, clinical studies are lacking to support this use. Use of peyote is illegal in the United States, except for religious purposes by the Native American Church.


Use of peyote is illegal in the United States. Clinical studies of peyote do not provide a basis for dosage recommendations. No standardization of preparations exists.


Contraindications have not been identified; peyote use may increase the risk of psychoses in individuals with mental health conditions.


Avoid use. Information regarding safety and efficacy during pregnancy and lactation is lacking.


None well documented.

Adverse Reactions

Symptoms of mild to moderate toxicity, including hallucinations, tachycardia, agitation, and mydriasis, have been reported with peyote use. Peyote buttons are bitter and may cause vomiting and other GI effects when consumed.


Few toxicological studies of peyote have been conducted. Mescaline is distributed into the liver and brain. In one clinical study, no chromosomal abnormalities due to peyote use were detected.

Scientific Family


L. williamsii is a small, fleshy, spineless cactus plant native to Mexico and southern parts of the United States, preferring scrub or limestone conditions. The plant is slow growing, forming clusters of grey-green bulbous shoots (up to 12 cm wide) close to the ground. The tops of the shoots (called "buttons") are harvested and dried. Peyote produces pink (sometimes white or yellow) flowers that open during the day, forming small (2 cm), edible, flesh-colored fruits. When mature, the fruits are dry and off-white colored and contain small (1 to 1.5 mm), pear-shaped black seeds.(Duke 2002, Kapadia 1968, Kapadia 1970, USDA 2021) A synonym of L. williamsii is Echinocactus williamsii.


Peyote buttons dating back to at least 3000 BC have been found at Texas archaeological sites. For thousands of years, Native Americans have used peyote for ritual and healing purposes. The plant has been traditionally used for pain (eg, toothache), rheumatism, colds, blindness, and alcoholism. Peyote use is illegal in the United States, except for religious purposes by the Native American Church.(Blum 1977, Carod-Artal 2015, Carstairs 2010, El-Seedi 2005)

Mescaline‐like compounds were explored as hallucinogens for military and intelligence purposes from the 1940s to 1960s. The Germans were the first to test mescaline as a "truth drug" in a military context. In the 1940s, the United States military started testing hallucinogenic substances as "truth drugs" for interrogation and behavior manipulation. After tests carried out using mescaline and other drugs in the 1950s, derivatives of mescaline were synthesized by the army for the exploration of possible "speech‐inducing" effects.(Passie 2018)


Peyote contains more than 60 hallucinogenic alkaloids from the phenylethylamine family, the principal alkaloid being mescaline. The mescaline content found in L. williamsii is about 0.4% fresh (undried) and 3% to 6% dried.(Bruhn 2008, Carod-Artal 2015, Dinis-Oliveira 2019) Other identified compounds include tetrahydroisoquinoline alkaloids (including peliotine, anhalonidine, lophophorine, and anhalonine), tyramine and its derivatives, and other alkaloidal amides.(Duke 1992, Kapadia 1970, Ma 1986, Monte 1997)

Uses and Pharmacology

The secondary metabolites found in peyote produce psychosis-like symptoms and can alter perception, feelings, thoughts, and mood, without being addictive.(Dinis-Oliveira 2019) Peyote is reported to initiate states of introspection and insight that have been described as being of a spiritual nature. Hallucinogens (eg, LSD, mescaline, psilocin) bind with high affinity and activate the serotonin 5-hydroxytryptamine (5-HT2A) receptor.(López-Giménez 2018)


It has been proposed that some psychedelics (including mescaline) have the potential to attenuate or even resolve autoimmunity by targeting psychosomatic origins, maladaptive chronic stress responses, inflammatory pathways, immune modulation, and enteric microbiome populations. Of classic psychedelics reviewed (eg, LSD, psilocybin, mescaline, ibogaine, N,N-dimethyltryptamine, 5-methoxy-N,N-dimethyltryptamine), mescaline was noted to exhibit the highest binding affinity to the 5-HT2A and 5-HT2C receptors.(Thompson 2020)

CNS effects

Clinical data

The current status of mescaline as a controlled substance limits the availability of the drug for research. As a result, very few clinical studies concerning the activity and potential therapeutic effects of mescaline have been conducted since the early 1970s.(Dinis-Oliveira 2019)

A study among healthy volunteers showed that a relatively large dose of mescaline (500 mg as mescaline sulfate) increased frontal cerebral blood flow.(Nichols 2016) A retrospective study among Native American Church members who used peyote occasionally for religious purposes showed no evidence of psychological or cognitive deficits according to standard neuropsychological tests of memory and attentional/executive functions.(Halpern 2005) Other analyses have also shown that use of mescaline and other psychedelics does not contribute to long-term mental health issues; however, this is still being debated.(Krebs 2013, Nesvåg 2015) Survey results from 452 adults who had used mescaline at least once in their life revealed that their most memorable mescaline experience was either in the top 5 or was the single most personally or spiritually meaningful experience in their lives for approximately 33% of respondents. In respondents diagnosed with a psychiatric disorder, the majority (86% with depression, 80% with anxiety, 76% with PTSD, 76% with alcohol misuse, and 68% with drug misuse) reported unexpected improvement in their condition after mescaline use. Greater intensity of insight during their mescaline experience was associated with improvement in those with depression, alcohol misuse, and drug misuse, whereas a greater intensity in mystical-type of experience was associated with improvements in those with PTSD.(Agin-Liebes 2021)

Hallucinogens (including mescaline) have been proposed for the treatment of some pathologies, including alcoholism and depression.(Dinis-Oliveira 2019) However, unlike for other hallucinogens (eg, LSD), recent clinical trials evaluating mescaline for such uses are lacking.


Use of peyote is illegal in the United States. Clinical studies of peyote do not provide a basis for dosage recommendations. No standardization of preparations exists.

Mescaline is mainly administered orally, but can also be smoked and insufflated. Tablets containing mescaline are typically ingested, or more commonly the cactus "buttons" are chewed or used to prepare infusions (eg, peyote cactus tea); when used via this route (eg, for hallucinogenic properties, in religious or therapeutic rituals), doses usually range from 200 to 400 mg of mescaline sulfate or 178 to 356 mg of mescaline hydrochloride, with the average amount contained in 3 to 6 cactus buds or roughly 10 to 20 g of dried peyote. However, concentrations of the compounds rely heavily on the species, geoclimatic and development conditions, cactus age, and the harvested part, among other factors, making it difficult to accurately estimate doses without previous extraction of mescaline.(Dinis-Oliveira 2019, Nichols 2004, Nichols 2016)

The time to onset of events is 1 to 3 hours and the duration is 10 to 12 hours. The half-life of ingested mescaline in humans is about 6 hours.(Dinis-Oliveira 2019)

Pregnancy / Lactation

Avoid use. Clinical information regarding safety and efficacy during pregnancy or lactation is lacking.


None well documented.

Adverse Reactions

Epidemiological studies suggest few adverse effects associated with the use of peyote for religious purposes. Peyote use may increase the risk of psychoses in individuals with mental health issues.(Halpern 2005) Peyote buttons are bitter and may cause vomiting and other GI effects when consumed.(Carstairs 2010) In animal studies, mescaline doses exceeding 20 to 60 mg/kg produced hypotension, bradycardia, and respiratory depression. Cardiovascular and respiratory effects in humans may be variable and dose dependent.(Barceloux 2012) Occurrence of flashbacks after using peyote are rare.(Dinis-Oliveira 2019)


Mescaline from peyote is distributed to the liver and brain.(Henry 2003) A review of the California Poison Control System database records from 1997 to 2008 suggest mild to moderate toxicity from peyote consumption or insufflation; adverse reactions include hallucinations, tachycardia, agitation, and mydriasis.(Carstairs 2010) No chromosomal abnormalities were found among Native Americans who used subhallucinogenic doses of peyote for ceremonial purposes compared with controls.(Dorrance 1975) Serious effects from peyote ingestion have been rarely described and include Mallory-Weiss lacerations from severe vomiting and botulism from ingestion of improperly stored peyote buttons.(Dinis-Oliveira 2019) Addiction and dependence are mostly absent, and most intoxications appear to be mild and unlikely to produce life-threatening symptoms.(Dinis-Oliveira 2019)

Symptoms of mescaline poisoning are consistent with a sympathomimetic toxidrome (eg, hyperreflexia, tachycardia, agitation, muscle stiffness, ataxia, seizures, mydriasis, sialorrhea, hyperthermia, paresthesia).(Dinis-Oliveira 2019)

Index Terms



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Agin-Liebes G, Haas TF, Lancelotta R, Uthaug MV, Ramaekers JG, Davis AK. Naturalistic use of mescaline is associated with self-reported psychiatric improvements and enduring positive life changes. ACS Pharmacol Transl Sci. 2021;4(2):543-552.33860184
Barceloux DG. Medical Toxicology of Drug Abuse: Synthesized Chemicals and Psychoactive Plants. Hoboken, NJ: John Wiley & Sons; 2012.
Blum K, Futterman SL, Pascarosa P. Peyote, a potential ethnopharmacologic agent for alcoholism and other drug dependencies: possible biochemical rationale. Clin Toxicol. 1977;11(4):459-472. doi:10.3109/15563657708988210201426
Bruhn JG, El-Seedi HR, Stephanson N, Beck O, Shulgin AT. Ecstasy analogues found in cacti. J Psychoactive Drugs. 2008;40(2):219-222. doi:10.1080/02791072.2008.1040063518720674
Carod-Artal FJ. Hallucinogenic drugs in pre-Columbian Mesoamerican cultures. Neurologia. 2015;30(1):42-49. doi:10.1016/j.nrl.2011.07.00321893367
Carstairs SD, Cantrell FL. Peyote and mescaline exposures: a 12-year review of a statewide poison center database. Clin Toxicol (Phila). 2010;48(4):350-353. doi:10.3109/1556365090358674520170392
Dinis-Oliveira RJ, Pereira CL, da Silva DD. Pharmacokinetic and pharmacodynamic aspects of peyote and mescaline: clinical and forensic repercussions. Curr Mol Pharmacol. 2019;12(3):184-194. doi:10.2174/187446721166618101015413930318013
Dorrance DL, Janiger O, Teplitz RL. Effect of peyote on human chromosomes. Cytogenetic study of the Huichol Indians of Northern Mexico. JAMA. 1975;234(3):299-302.1174242
Duke J. Handbook of Biologically Active Phytochemicals and Their Activities. CRC Press Inc; 1992.
Duke JA, Bogenschutz-Godwin MJ, duCellier J, Duke PK. Handbook of Medicinal Herbs. 2nd ed. CRC Press; 2002.
El-Seedi HR, De Smet PA, Beck O, Possnert G, Bruhn JG. Prehistoric peyote use: alkaloid analysis and radiocarbon dating of archaeological specimens of Lophophora from Texas. J Ethnopharmacol. 2005;101(1-3):238-242. doi:10.1016/j.jep.2005.04.02215990261
Halpern JH, Sherwood AR, Hudson JI, Yurgelun-Todd D, Pope HG Jr. Psychological and cognitive effects of long-term peyote use among Native Americans. Biol Psychiatry. 2005;58(8):624-631. doi:10.1016/j.biopsych.2005.06.03816271313
Henry JL, Epley J, Rohrig TP. The analysis and distribution of mescaline in postmortem tissues. J Anal Toxicol. 2003;27(6):381-382. doi:10.1093/jat/27.6.38114516493
Kapadia GJ, Fayez MB. Peyote constituents: chemistry, biogenesis, and biological effects. J Pharm Sci. 1970;59(12):1699-1727. doi:10.1002/jps.26005912025499699
Kapadia GJ, Highet RJ. Peyote alkaloids. IV. Structure of peyonine, novel beta-phenethylpyrrole from Lophophora williamsii. J Pharm Sci. 1968;57(1):191-192. doi:10.1002/jps.26005701465652132
Krebs TS, Johansen PØ. Psychedelics and mental health: a population study. PLoS One. 2013; 8(8):e63972. doi:10.1371/journal.pone.006397223976938
López-Giménez JF, González-Maeso J. Hallucinogens and serotonin 5-HT2A receptor-mediated signaling pathways. Curr Top Behav Neurosci. 2018;36:45-73. doi:10.1007/7854_2017_47828677096
Lophophora williamsii. USDA, NRCS. 2021. The PLANTS Database (, 27 July 2021). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Ma WW, Jiang XY, Cooks RG, et al. Cactus alkaloids, LXI. Identification of mescaline and related compounds in eight additional species using tlc and ms/ms. J Nat Prod. 1986;49(4):735-737. doi:10.1021/np50046a0503783171
Monte AP, Waldman SR, Marona-Lewicka D, et al. Dihydrobenzofuran analogues of hallucinogens. 4. Mescaline derivatives. J Med Chem. 1997;40(19):2997-3008. doi:10.1021/jm970219x9301661
Nesvåg R, Bramness JG, Ystrom E, Suzanne Krebs T, Johansen PØ. The link between use of psychedelic drugs and mental health problems. J Psychopharmacol. 2015;29(9):1035-1036.26395581
Nichols DE. Hallucinogens. Pharmacol Ther. 2004;101(2):131-181. doi:10.1016/j.pharmthera.2003.11.00214761703
Nichols DE. Psychedelics. Pharmacol Rev. 2016;68 (2):264-355. doi:10.1124/pr.115.01147826841800
Passie T, Benzenhöfer U. MDA, MDMA, and other "mescaline-like" substances in the US military's search for a truth drug (1940s to 1960s). Drug Test Anal. 2018;10(1):72-80. doi:10.1002/dta.229228851034
Thompson A, Szabo A. Psychedelics as a novel approach to treating autoimmune conditions. Immunol Lett. 2020;228:45-54. doi:10.1016/j.imlet.2020.10.00133035575

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