Psilocybin mushroom

"Magic Mushroom" redirects here. For other uses, see Magic Mushroom (disambiguation).

"Psychedelic mushroom" redirects here. It is not to be confused with Psychoactive mushroom.

Psilocybe cubensis

Psilocybin mushrooms are fungi that contain the psychoactive compounds psilocybin and psilocin. There are multiple colloquial terms for psilocybin mushrooms, the most common being shrooms or magic mushrooms.^[1][2] Biological genera containing psilocybin mushrooms include Agrocybe, Conocybe, Copelandia, Galerina, Gerronema, Gymnopilus, Hypholoma, Inocybe, Mycena, Panaeolus, Pluteus, and Psilocybe. There are approximately 190 species of psilocybin mushrooms and most of them fall in the genus Psilocybe.

History

Early

World-wide distribution of Psilocybe cubensis

There is some archaeological evidence for the use of psyilocybin-containing mushrooms in ancient times. Several mesolithic rock paintings from Tassili n'Ajjer (a prehistoric North African site identified with the Capsian culture) have been identified by author Giorgio Samorini as possibly depicting the shamanic use of mushrooms, possibly Psilocybe.^[3] Hallucinogenic species of Psilocybe have a history of use among the native peoples of Mesoamerica for religious communion, divination, and healing, from pre-Columbian times up to the present day. Mushroom-shaped statuettes found at archaeological sites seem to indicate that ritual use of hallucinogenic mushrooms is quite ancient.^[4] Mushroom stones and motifs have been found in Mayan temple ruins in Guatemala,^[5] though there is considerable controversy as to whether these objects indicate the use of hallucinogenic mushrooms or whether they had some other significance with the mushroom shape being simply a coincidence.^{[citation needed]} More concretely, a statuette dating from ca. 200 AD and depicting a mushroom strongly resembling Psilocybe mexicana was found in a west Mexican shaft and chamber tomb in the state of Colima. Hallucinogenic Psilocybe were known to the Aztecs as teonanácatl (literally "divine mushroom" - agglutinative form of teó (god, sacred) and nanácatl (mushroom) in Náhuatl) and were reportedly served at the coronation of the Aztec ruler Moctezuma II in 1502. Aztecs and Mazatecs referred to psilocybin mushrooms as genius mushrooms, divinatory mushrooms, and wondrous mushrooms, when translated into English.^[6] Bernardino de Sahagún reported ritualistic use of teonanácatl by the Aztecs, when he traveled to Central America after the expedition of Hernán Cortés.

After the Spanish conquest, Catholic missionaries campaigned against the "pagan idolatry," and as a result the use of hallucinogenic plants and mushrooms like other pre-Christian traditions was quickly suppressed.^[5] The Spanish believed the mushroom allowed the Aztecs and others to communicate with "devils". In converting people to Catholicism, the Spanish pushed for a switch from teonanácatl to the Catholic sacrament of the Eucharist. Despite this history, in some remote areas, the use of teonanácatl has remained.

The first mention of hallucinogenic mushrooms in the Western medicinal literature appeared in the London Medical and Physical Journal in 1799: a man had served Psilocybe semilanceata mushrooms that he had picked for breakfast in London's Green Park to his family. The doctor who treated them later described how the youngest child "was attacked with fits of immoderate laughter, nor could the threats of his father or mother refrain him."^[7]

Modern

Psilocybe subaeruginascens

In 1955, Valentina and R. Gordon Wasson became the first Westerners to actively participate in an indigenous mushroom ceremony. The Wassons did much to publicize their discovery, even publishing an article on their experiences in Life in 1957.^[8] In 1956 Roger Heim identified the hallucinogenic mushroom that the Wassons had brought back from Mexico as Psilocybe, and in 1958, Albert Hofmann first identified psilocin and psilocybin as the active compounds in these mushrooms.

Inspired by the Wassons' Life article, Timothy Leary traveled to Mexico to experience hallucinogenic mushrooms firsthand. Upon returning to Harvard in 1960, he and Richard Alpert started the Harvard Psilocybin Project, promoting psychological and religious study of psilocybin and other hallucinogenic drugs. After Leary and Alpert were dismissed by Harvard in 1963, they turned their attention toward promoting the psychedelic experience to the nascent hippie counterculture.

The popularization of entheogens by Wasson, Leary, authors Terence McKenna and Robert Anton Wilson, and others has led to an explosion in the use of hallucinogenic Psilocybe throughout the world. By the early 1970s, a number of psychoactive Psilocybe species were described from temperate North America, Europe, and Asia and were widely collected. Books describing methods of cultivating Psilocybe cubensis in large quantities were also published. The availability of hallucinogenic Psilocybe from wild and cultivated sources has made it among the most widely used of the hallucinogenic drugs.

At present, hallucinogenic mushroom use has been reported among a number of groups spanning from central Mexico to Oaxaca, including groups of Nahua, Mixtecs, Mixe, Mazatecs,^[9] Zapotecs, and others. An important figure of mushroom usage in Mexico was Maria Sabina.

Effects

Psilocybin

The effects of Psilocybin mushrooms come from psilocybin and psilocin. They do create short-term increases in tolerance of users, thus making it difficult to abuse them because the more often they are taken within a short period of time, the weaker the resultant effects are.^[10] Poisonous (sometimes lethal) wild picked mushrooms can be easily mistaken for psilocybin mushrooms. When psilocybin is ingested, it is broken down to produce psilocin, which is responsible for the hallucinogenic effects.^[10][11]

As with many psychedelic substances, the effects of psychedelic mushrooms are subjective and can vary considerably among individual users. The mind-altering effects of psilocybin-containing mushrooms typically last anywhere from 3 to 8 hours depending on dosage, preparation method, and personal metabolism. However, the effects can seem to last much longer because of psilocybin's ability to alter time perception.^[12][13]

Despite risks, mushrooms may do much less damage in the UK than other recreational drugs - whereas alcohol was considered to be the most damaging (although magic mushrooms are also much less readily available).

Some users suffer from hallucinogen persisting perception disorder although how many, and why, is unknown. Perceptual disturbances causing discomfort are rarely reported after using psylocybin, but they may be more likely if the drug is mixed with cannabis^[14]. There have been reports of such disturbances lasting 5 years or more^[15]. Magic mushrooms have also been controversially associated with long term effects such as panic attacks, depression and paranoid delusions.^[16] On the other hand, magic mushrooms were rated as causing some of the least damage in the UK compared to other recreational drugs by experts in a study by the Independent Scientific Committee on Drugs.^[17] Other researchers have said that the main chemical component (psilocybin) is "remarkably non-toxic to the body's organ systems", explaining that the risks are indirect: higher dosages are more likely to cause fear and may result in dangerous behavior.^[18]

One study found that the most desirable results may come from starting with very low doses first, and trying slightly higher doses over months. The researchers explain that the peak experiences occur at quantities that are only slightly lower than a sort of anxiety threshold. Although risks of experiencing fear and anxiety increased somewhat consistently along with dosage and overall quality of experience, at dosages exceeding the individual's threshold, there was suddenly greater increases in anxiety than before. In other words, after finding the optimum dose, there are diminishing returns for using more (since risks of anxiety now increase at a greater rate).^[18]

Sensory

Noticeable changes to the audio, visual, and tactile senses may become apparent around thirty minutes to an hour after ingestion. These shifts in perception visually include enhancement and contrasting of colors, strange light phenomena (such as auras or "halos" around light sources), increased visual acuity, surfaces that seem to ripple, shimmer, or breathe; complex open and closed eye visuals of form constants or images, objects that warp, morph, or change solid colors; a sense of melting into the environment, and trails behind moving objects. Sounds seem to be heard with increased clarity; music, for example, can often take on a profound sense of cadence and depth. Some users experience synesthesia, wherein they perceive, for example, a visualization of color upon hearing a particular sound.^[19]

Emotional

Psilocin

As with other psychedelics such as LSD, the experience, or "trip," is strongly dependent upon set and setting. A negative environment could likely induce a bad trip, whereas a comfortable and familiar environment would allow for a pleasant experience. Many users find it preferable to ingest the mushrooms with friends, people they're familiar with, or people who are also 'tripping'.^[20][21]

Spiritual and well being

In 2006, the United States government funded a randomized and double-blinded study by Johns Hopkins University which studied the spiritual effects of psilocybin in particular. That is, they did not use mushrooms specifically (in fact, each individual mushroom piece can vary wildly in psilocybin and psilocin content^[22]). The study involved 36 college-educated adults (average age of 46) who had never tried psilocybin nor had a history of drug use, and who had religious or spiritual interests. The participants were closely observed for eight-hour intervals in a laboratory while under the influence of psilocybin mushrooms^[23].

One-third of the participants reported that the experience was the single most spiritually significant moment of their lives and more than two-thirds reported it was among the top five most spiritually significant experiences. Two months after the study, 79% of the participants reported increased well-being or satisfaction; friends, relatives, and associates confirmed this. They also reported anxiety and depression symptoms to be decreased or completely gone.

Despite highly controlled conditions to minimize adverse effects, 22% of subjects (8 of 36) had notable experiences of fear, some with paranoia. The authors, however, reported that all these instances were "readily managed with reassurance."^[23]

See psilocybin for more details

As medicine

For more health related information on the main psycho-active ingredient, see psilocybin

Psilocybe villarrealiae, which is only known to a small area of Mexico

There have been calls for medical investigation of the use of synthetic and mushroom-derived psilocybin for the development of improved treatments of various mental conditions, including chronic cluster headaches,^[24] following numerous anecdotal reports of benefits. There are also several accounts of psilocybin mushrooms sending both obsessive-compulsive disorders ("OCD") and OCD-related clinical depression (both being widespread and debilitating mental health conditions) into complete remission immediately and for up to months at a time, compared to current medications which often have both limited efficacy^[25] and frequent undesirable side-effects.^[26] One such study states:

"Developing drugs that are more effective and faster acting for the treatment of OCD is of utmost importance and until recently, little hope was in hand. A new potential avenue of treatment may exist. There are several reported cases concerning the beneficial effects of hallucinogenic drugs (psilocybin and LSD), potent stimulators of 5-HT2A and 5-HT2C receptors, in patients with OCD (Brandrup and Vanggaard, 1977, Rapoport, 1987, Moreno and Delgado, 1997) and related disorders such as body dysmorphic disorder (Hanes, 1996)."^[26]

"[I]f it can be established that this class of drug can indeed lead to rapid and substantial reduction in OCD symptoms, then it opens the way for a variety of future studies with new drugs that might possibly have the anti-OCD but not the psychedelic effects. [...] Psilocybin, LSD, and mescaline are extremely potent agonists at 5-HT2A and 5-HT2C receptors and their binding potency to these receptors is correlated with their human potency as hallucinogens (Glennon et al., 1984). The acute improvement in symptoms described in the published case reports (Brandrup and Vanggaard, 1977, Rapoport, 1987, Moreno and Delgado, 1997) suggests that interactions with 5-HT2A and 5-HT2C receptors may be an essential component of anti-OCD drug action. The observations that administration of the non-selective 5-HT antagonists metergoline or ritanserin exacerbate OCD symptoms further supports this view."^[26]

Dosage

Dosage of mushrooms containing psilocybin depends on the potency of the mushroom (the total psilocybin and psilocin content of the mushrooms), which varies significantly both between species and within the same species, but is typically around 0.5-2% of the dried weight of the mushroom. A typical dose of the rather common species, Psilocybe cubensis, is approximately 1 to 2.5 grams,^[27] while about 2.5 to 5 grams^[27] dried mushroom material is considered a strong dose. Above 5 dried grams is often considered a heavy dose.

Alkaloid Concentration of Dried Psilocybin Mushrooms^[28]

Name	Psilocybin [%]	Psilocin [%]	Baeocystin [%]	Total [%]
Conocybe cyanopus	0.930–0.450[29]	0.70-0.00[29]	0.030-0.100[29]	1.03–0.55
Conocybe smithii	n/a	n/a	0.40–0.80	0.40–0.80+ [29]
Gymnopilus purpuratus	0.34%	0.29%	0.05%	0.68% [30]
Gymnopilus validipes	0.12%[31]	–	–	0.12%+
Panaeolus cinctulus	0.150%–0.600[29]	0.00%[29]	0.001%–0.005[29]	0.151%–0.605
Psilocybe azurescens	1.78	0.38	0.35	2.51
Psilocybe baeocystis	0.85	0.59	0.10	1.54
Psilocybe bohemica	0.93[30]–1.34%	0.11–0.28[30]	0.02%[30]	1.06–1.47%
Psilocybe cubensis	0.63%[30]	0.25[30]–0.60%	0.02[30]–0.025%	0.90–1.26%
Psilocybe cyanescens	0.85	0.36	0.03	1.24
Psilocybe cyanofibrillosa	0.21	0.04	n/a	0.25+
Psilocybe hoogshagenii	0.60	0.10	n/a	0.70+
Psilocybe liniformans	0.16	n/a	0.005	0.17+
Psilocybe semilanceata	0.98%	0.02%	0.36%	1.36%
Psilocybe stuntzii	0.36	0.12	0.02	0.5
Psilocybe tampanensis	0.68	0.32	n/a	1.00+
Psilocybe weilii	0.61	0.27	0.05	0.93

The concentration of active psilocybin mushroom compounds varies not only from species to species, but also from mushroom to mushroom inside a given species, subspecies or variety. The same holds true even for different parts of the same mushroom. In the species Psilocybe samuiensis Guzmán, Bandala and Allen, the dried cap of the mushroom contains the most psilocybin at about 0.23%–0.90%.^[32] The mycelia contain about 0.24%–0.32%.^[32]

Legality

Main article: Legal status of psilocybin mushrooms

Psilocybe cyanofriscosa

Psilocybin and psilocin are listed as Schedule I drugs under the United Nations 1971 Convention on Psychotropic Substances.^[33] Schedule I drugs are deemed to have a high potential for abuse and are not recognized for medical use. However, psilocybin mushrooms are not covered by UN drug treaties.

From a letter, dated Sept 13, 2001, from Herbert Schaepe, Secretary of the UN International Narcotics Control Board, to the Dutch Ministry of Health:^[34]

As you are aware, mushrooms containing the above substances are collected and used for their hallucinogenic effects. As a matter of international law, no plants (natural material) containing psilocine and psilocybin are at present controlled under the Convention on Psychotropic Substances of 1971. Consequently, preparations made of these plants are not under international control and, therefore, not subject of the articles of the 1971 Convention. It should be noted, however, that criminal cases are decided with reference to domestic law, which may otherwise provide for controls over mushrooms containing psilocine and psilocybin. As the Board can only speak as to the contours of the international drug conventions, I am unable to provide an opinion on the litigation in question.

Psilocybin mushrooms are regulated or prohibited in many countries, often carrying severe legal penalties (for example, the U.S. Psychotropic Substances Act, the UK Misuse of Drugs Act 1971 and Drugs Act 2005, and the Canadian Controlled Drugs and Substances Act).

Magic mushrooms in their fresh form still remain legal in some countries including Spain, Austria, and Canada. On November 29, 2008, The Netherlands announced it would ban the cultivation and use of psilocybin-containing fungi beginning December 1, 2008.^[35] The UK ban on fresh mushrooms (dried ones were illegal as they were considered a psilocybin-containing preparation) introduced in 2005 came under much criticism, but was rushed through at the end of the 2001-2005 Parliament; until then magic mushrooms had been sold in the UK.

New Mexico appeals court ruled on June 14, 2005, that growing psilocybin mushrooms for personal consumption could not be considered "manufacturing a controlled substance" under state law. However it still remains illegal under federal law.^[36][37]

See also

Fungi portal

• Entheogen
• Ethnomycology
• List of Psilocybin mushrooms
• Mario Bros. mushroom
• Medicinal mushrooms
• Mystical psychosis
• Psychedelic
• Psychedelic drug
• Psychonautics
• Shamanism
• Terence McKenna

Notes

1. ^ Kuhn, Cynthia; Swartzwelder, Scott and Wilson, Wilkie (1998 & 2003). Buzzed: The Straight Facts about the Most Used and Abused Drugs from Alcohol to Ecstasy. W.W. Norton & Company Inc. p. 83. ISBN 0-393-32493-1. 
2. ^ "Taking care of ourselves". Cornell University: Women's Resource Center. http://wrc.dos.cornell.edu/handbook/Chapter5.html. Retrieved 2007-04-04. 
3. ^ "The oldest Representations of Hallucinogenic Mushrooms in the World.". www.samorini.net/. Archived from the original on 2006-01-16. http://web.archive.org/web/20060116104741/www.samorini.net/doc/sam/sah_int.htm. Retrieved 2007-04-04. 
4. ^ John M. Allegro"The Sacred Mushroom And The Cross"
5. ^ ^{a b} Stamets, Paul (1996) [1996]. Psilocybin Mushrooms of the World. Ten Speed Press. p. 11. ISBN 0898158397. 
6. ^ Stamets, Paul (1996) [1996]. Psilocybin Mushrooms of the World. Ten Speed Press. p. 7. ISBN 0898158397. 
7. ^ Everard Brande (1799). "On A Poisonous Species of Agaric". London Medical and Physical Journal 11 (November 16): 41–44. http://www.erowid.org/references/refs_view.php?A=ShowDoc1&ID=6331. 
8. ^ Wasson RG (1957). "Seeking the magic mushroom". Life (May 13): 100–120.  article reproduced online
9. ^ Johnson, Jean Bassett (1939). "The Elements of Mazatec Witchcraft". Gothenburg, Sweden: Ethnological Studies, No. 9. 
10. ^ ^{a b} "Psilocybin Fast Facts". National Drug Intelligence Center. http://www.usdoj.gov/ndic/pubs6/6038/index.htm. Retrieved 2007-04-04. 
11. ^ The Good Drugs Guide. "Magic Mushrooms–Frequently Asked Questions". Frequently Asked Questions. The Good Drugs Guide. http://www.thegooddrugsguide.com/mushrooms/faq.htm#01. Retrieved 2007-01-04. 
12. ^ Erowid and contributors (2006). "Effects of Psilocybin Mushrooms" (shtml). Erowid. http://www.erowid.org/plants/mushrooms/mushrooms_effects.shtml. Retrieved 2006-12-01. 
13. ^ The Good Drugs Guide. "Psychedelic Effects of Magic Mushrooms". The Good Drugs Guide. http://www.thegooddrugsguide.com/mushrooms/psychedelic.htm. Retrieved 2006-12-01. 
14. ^ [Espiard et al., 2005 M.L. Espiard, L. Lecardeur, P. Abadie, I. Halbecq and S. Dollfus, Hallucinogen persisting perception disorderafter psilocybin consumption: a case study, Eur. Psychiatry 20 (2005), pp. 458–460]
15. ^ [G. Aldurra and J.W. Crayton, Improvement of hallucinogen persisting perception disorder by treatment with a combination offluoxetine and olanzapine: case report, J. Clin. Psychopharmacol. 21 (2001), pp. 343–344.]
16. ^ University of New South Wales, Faculty of Medicine, Magic Mushrooms fact sheet
17. ^ Drugs that Cause the Most Harm, in The Economist
18. ^ ^{a b} John Hopkins probes "Sacred" Mushroom Chemical, newswise.com
19. ^ D.M. Turner"Psilocybin Mushrooms:The Extraterrestrial Invasion Of Earth"
20. ^ Stamets, Paul (1996) [1996]. Psilocybin Mushrooms of the World. Ten Speed Press. ISBN 0898158397. 
21. ^ Simon G.Powell"The Psilocybin Solution:Prelude To A Paradigm Shift"
22. ^ Stafford PJ. (1992). Psychedelics Encyclopedia. Berkeley, California: Ronin Publishing. ISBN 0-914171-51-8.
23. ^ ^{a b} "RR Griffiths, WA Richards, U McCann, R Jesse. Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance" (PDF). Psychopharmacology187(3):268-83. August 2006. http://www.csp.org/psilocybin/Hopkins-CSP-Psilocybin2006.pdf. Retrieved 2008-09-25. 
24. ^ Clusterbusters. "Psilocybin Mushrooms". http://www.clusterbusters.com/hallucinogens.html. Retrieved 2006-12-01. 
25. ^ "Effects of Psilocybin in Obsessive-Compulsive Disorder". http://www.sex.org/research/psilo/azproto.html. :"In spite of the established efficacy of potent 5-HT reuptake inhibitors in the treatment of OCD ... the length of time required for improvement of patients undergoing treatment with 5-HT reuptake inhibitors appears to be quite long ... and the percentage of patients having satisfactory responses may only approach 50 percent, and most patients that do improve only have a 30 to 50% decrease in symptoms (Goodman et al., 1990)"
26. ^ ^{a b c} "Effects of Psilocybin in Obsessive-Compulsive Disorder". http://www.maps.org/research/psilo/azproto.html. 
27. ^ ^{a b} Erowid (2006). "Dosage Chart for Psychedelic Mushrooms" (shtml). Erowid. http://www.erowid.org/plants/mushrooms/mushrooms_dose.shtml. Retrieved 2006-12-01. 
28. ^ "Approximate Alkaloid Content of selected Psilocybe mushrooms". www.erowid.org. 2009-03-27. http://www.erowid.org/plants/mushrooms/mushrooms_info4.shtml. Retrieved 2010-05-30. 
29. ^ ^{a b c d e f g} "The Psilocybe Mushroom FAQ, Version 1.2". www.sporelab.com. http://www.sporelab.com/faq-psil.htm#Panaeolus%20subbalteatus. Retrieved 2010-01-04. 
30. ^ ^{a b c d e f g} "Dr. Gartz Series Extraction (www.tacethno.com)". http://www.tacethno.com/info/psilocybe/gartz1.txt. Retrieved 2010-05-30. 
31. ^ Psilocybin Mushrooms of the World. Books.google.com. http://books.google.com/books?id=10HiGVo94FUC&pg=PA183&lpg=PA183&dq=%22gymnopilus+spectabilis%22+psilocybin&source=bl&ots=wZYizsNhrw&sig=_LJY10J4SvD8yfZTzA9_nkVsYwk&hl=en&ei=zcBbS9HwBI7AsQOgkPSwCg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CAcQ6AEwADgK#v=onepage&q=%22gymnopilus%20spectabilis%22%20psilocybin&f=false. Retrieved 2010-05-30. 
32. ^ ^{a b} USA (2010-04-01). "Abstract:J Ethnopharmacol. 1994 Jul 8;43(2):73-80. Ethnomycology, biochemistry, and cultivation of Psilocybe samuiensis Guzmán, Bandala and Allen, a new psychoactive fungus from Koh Samui, Thailand. Gartz J, Allen JW, Merlin MD". Ncbi.nlm.nih.gov. http://www.ncbi.nlm.nih.gov/pubmed/7967658. Retrieved 2010-05-30. 
33. ^ "List of psychotropic substances under international control" (PDF). International Narcotics Control Board. August 2003. http://www.incb.org/pdf/e/list/green.pdf. Retrieved 2007-06-25. 
34. ^ Schaepe, Herbert (2001-09-13). "UN's INCB Psilocybin Mushroom Policy". Erowid.org. http://www.erowid.org/plants/mushrooms/mushrooms_law12.shtml. Retrieved 2010-05-30. 
35. ^ "RTÉ News: 'Shrooms to become illegal in Holland". RTÉ News. November 2008. http://www.rte.ie/news/2008/1128/mushrooms.html. Retrieved 2008-11-28. 
36. ^ "FindLaw". caselaw.lp.findlaw.com. http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=nm&vol=05ca-099&invol=2. Retrieved 2010-01-03. 
37. ^ "Erowid Psilocybin Mushroom Vault : Legal Status". www.erowid.org. http://www.erowid.org/plants/mushrooms/mushrooms_law.shtml. Retrieved 2010-01-03. 

References

• Allen, John W. (1997). Magic Mushrooms of the Pacific Northwest. Seattle: Raver Books and John W. Allen. ISBN 1-58214-026-X. 
• Letcher, Andy (2006). Shroom: A Cultural History of the Magic Mushroom. London: Faber and Faber Limited. ISBN 0-060-82828-5. 
• Nicholas, L. G; Ogame, Kerry (2006). Psilocybin Mushroom Handbook: Easy Indoor and Outdoor Cultivation. Quick American Archives. ISBN 0-932551-71-8. 
• Stamets, Paul (1993). Growing Gourmet and Medicinal Mushrooms. Berkeley: Ten Speed Press. ISBN 1-58008-175-4. 
• Stamets, Paul; Chilton, J.S. (1983). Mushroom Cultivator, The. Olympia: Agarikon Press. ISBN 0-9610798-0-0. 
• Stamets, Paul (1996). Psilocybin Mushrooms of the World. Berkeley: Ten Speed Press. ISBN 0-9610798-0-0. 
• Kuhn, Cynthia; Swartzwelder, Scott; Wilson, Wilkie (1998 & 2003). Buzzed: The Straight Facts about the Most Used and Abused Drugs from Alcohol to Ecstasy. New York: W.W. Norton & Company Inc. ISBN 0-393-32493-1. 
• R. Gordon Wasson, The Wondrous Mushroom: Mycolatry in Mesoamerica
• Alvaro Estrada, Maria Sabina: Her Life and Chants
• Terence McKenna, Food of the Gods
• Ole Högberg, Flugsvampen och människan. Section concerning the berserker myth is published online [1]^{[dead link]} In Swedish and PDF format ISBN 91-7203-555-2

External links

• The Vaults of Erowid - Psilocybin Mushrooms
• Jeremy Bigwood: Scientific Publications (archived at Wayback Machine)
• International Legal Status of Psilocybin Mushrooms Ananda Schouten, Erowid, 2004
• UN's INCB Psilocybin Mushroom Policy Herbert Schaepe, 2001
• Hallucinogenic mushrooms EMCDDA, Lisbon, June 2006
• Hallucinogenic mushrooms: the challenge of responding to naturally occurring substances in an electronic age EMCDDA, Drugs in Focus 15
• Psilocybes in Medicine from the "International Journal of Psychoactive Mushrooms" FMRC