|Summary sheet: Psilocybin mushrooms|
Psilocybin mushrooms (also known as magic mushrooms, psychedelic mushrooms, and shrooms) refers to a family of psychoactive mushrooms that contain the psychedelic tryptamine psilocybin. Psilocybin mushrooms occur on all continents and consist of more than 200 species, the most potent of which belong to the genus Psilocybe. Like other psychedelics, psilocybin mushrooms produce their effects by acting on serotonin receptors in the brain.
Imagery found on prehistoric rock art suggests that the use of psilocybin mushrooms predates recorded history. In Mesoamerica, they have been consumed in ritual ceremonies for 3000 years. They were introduced to the West in 1955 by Gordon R. Wasson. In the 1960s, psilocybin was widely used in the experimental research of mental disorders and in psychotherapy. Popularization by counterculture figures like Timothy Leary led to an explosion of recreational use and resulted in its prohibition in 1970. Today, psilocybin mushrooms are one of the most popular psychedelics and the subject of renewed interest by researchers and clinicians.
The intensity and duration of effects produced by psilocybin mushrooms can vary greatly depending on factors such as species and batch. Common doses of the popular strain P. cubensis range from 2 to 3.5 grams and last for 4 to 6 hours. Notable effects include geometric visual hallucinations, time distortion, enhanced introspection, and ego loss. Psilocybin mushrooms are commonly described by users to evoke entheogenic and mystical-type experiences that can facilitate introspection and personal growth.
Unlike most highly prohibited substances, psilocybin mushrooms are considered to be non-addictive and have low toxicity. Nevertheless, adverse psychological reactions such as anxiety, paranoia, delusions and psychosis can always occur, particularly among those predisposed to mental illness. For this reason, it is highly advised to use harm reduction practices if using this substance.
- 1 History and culture
- 2 Chemistry
- 3 Pharmacology
- 4 Subjective effects
- 5 Natural occurrence
- 6 Dosage and preparation
- 7 Research
- 8 Toxicity and harm potential
- 9 Legal status
- 10 See also
- 11 External links
- 12 Literature
- 13 References
History and culture
There is evidence that suggests that psychoactive mushrooms have been used by humans in religious ceremonies for thousands of years. Murals dated 9000 to 7000 BCE found in the Sahara desert in southeast Algeria depict horned beings dressed as dancers holding mushroom-like objects. 6,000-year-old pictographs discovered near the Spanish town of Villar del Humo illustrate several mushrooms that have been tentatively identified as Psilocybe hispanica, a hallucinogenic species native to the area.
Archaeological artifacts from Mexico have also been interpreted by some scholars as evidence for ritual and ceremonial usage of psychoactive mushrooms in the Mayan and Aztec cultures of Mesoamerica. In Nahuatl, the language of the Aztecs, the mushrooms were called teonanácatl, or "God's flesh". Following the arrival of Spanish explorers to the New World in the 16th century, chroniclers reported the use of mushrooms by the natives for ceremonial and religious purposes. Accounts describe mushrooms being eaten in festivities for the accession of emperors and the celebration of successful business trips by merchants. After the defeat of the Aztecs, the Spanish forbade traditional religious practices and rituals that they considered "pagan idolatry", including ceremonial mushroom use. For the next four centuries, the Indians of Mesoamerica hid their use of entheogens from the Spanish authorities.
American banker and amateur ethnomycologist R. Gordon Wasson studied the ritual use of psychoactive mushrooms by the native population of a Mazatec village in Mexico. In 1957, Wasson described the psychedelic visions that he experienced during these rituals in "Seeking the Magic Mushroom", an article published in the popular American weekly Life magazine. Later the same year they were accompanied on a follow-up expedition by French mycologist Roger Heim, who identified several of the mushrooms as Psilocybe species.
Heim cultivated the mushrooms in France, and sent samples for analysis to Albert Hofmann, a chemist employed by the Swiss pharmaceutical company Sandoz (now Novartis). Hofmann, who had in 1938 created LSD, led a research group that isolated and identified the psychoactive compounds from Psilocybe mexicana. He and his colleagues later synthesized a number of compounds chemically related to the naturally occurring psilocybin, to see how structural changes would affect psychoactivity. These included 4-HO-DET and 4-AcO-DMT. Sandoz marketed and sold pure psilocybin under the name Indocybin to physicians and clinicians worldwide without any reports of serious complications.
In the early 1960s, Harvard University became a testing ground for psilocybin, through the efforts of Timothy Leary and his associates Ralph Metzner and Richard Alpert. Leary obtained synthesized psilocybin from Hofmann through Sandoz pharmaceutical. Some studies, such as the Concord Prison Experiment, suggested promising results using psilocybin in clinical psychiatry. Leary and Alpert's zealous advocacy for widespread hallucinogen use led to a well-publicized termination from Harvard. In response to concerns about the increase in unauthorized use of psychedelic substances by the general public, psilocybin and other hallucinogens exoeruebce negative press and faced increasingly restrictive laws.
In the United States, laws were passed in 1966 that prohibited the production, trade, or ingestion of hallucinogenic substances. Sandoz stopped producing LSD and psilocybin the same year. Further backlash against LSD usage swept psilocybin along with it into the Schedule I category of illicit substances in 1970. Subsequent restrictions on the use of these substances in human research made funding for such projects difficult to obtain, and scientists who worked with psychedelic drugs faced being "professionally marginalized".
In the 1990s, hallucinogens and their effects on human consciousness were again the subject of scientific study, particularly in Europe. Advances in the neurosciences and the availability of brain imaging techniques have provided a reason for using substances like psilocybin to probe the "neural underpinnings of psychotic symptom formation including ego disorders and hallucinations". Recent studies in the United States have attracted attention from the popular press and thrust psilocybin into the vogue.
Psilocybin, or 4-phosphoryloxy-N,N-dimethyltryptamine (4-PO-DMT) is a prodrug that is converted into the pharmacologically active compound psilocin in the body by a dephosphorylation reaction mediated by alkaline phosphatase enzymes. Both psilocybin and psilocin are organic tryptamine compounds. They are chemically related to the amino acid tryptophan, and structurally similar to the neurotransmitter serotonin.
Tryptamines share a core structure comprised of a bicyclic indole heterocycle attached at R3 to an amino group via an ethyl side chain. Psilocybin is substituted at R4 of its indole heterocycle with a phosphoryloxy (-PO) functional group. It also contains two methyl groups CH3- bound to the terminal amine RN. This makes psilocybin the 4-phosphoryloxy ring-substituted analog of DMT..
Psilocybin and psilocin occur in their pure forms as white crystalline powders. Both are unstable in light, particularly while in solution, although their stability at low temperatures in the dark under an inert atmosphere is very good.
Psilocybin acts as a prodrug to psilocin, meaning it is not active until it is converted into psilocin in the body. Upon entering the body, psilocybin is dephosphorylated to psilocin in the intestinal mucosa by alkaline phosphatase and nonspecific esterase.
Psilocin's psychedelic effects are believed to come from its agonist activity on serotonin 5-HT2A/C and 5-HT1A receptors. While 5-HT2A receptor agonism is considered necessary for hallucinogenic activity, the role of other receptor subtypes is much less understood.
The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. These effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances of inducing a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.
- Sedation - Psilocybin is reported to be be relaxing, stoning and mildly sedating. This sense of sedation is often accompanied by compulsive yawning.
- Spontaneous bodily sensations - The "body high" of psilocybin can be described as a pleasurable, soft and all-encompassing tingling sensation or glow. This maintains a consistent presence that steadily rises with the onset and hits its limit once the peak has been reached. Once the peak of the experience or sensation is reached it can feel incredibly euphoric and tranquil or heavy and immobilizing depending on the dose.
- Perception of bodily heaviness- This effect corresponds to the general sense of sedation and relaxation that characterizes psilocybin experiences, this manifests as a bodily heaviness that discourages movement but is typically only prominent during the first half of the experience. This particular physical effect seems to be more commonly experienced and pronounced with certain “woodlover” species of mushrooms such as Psilocybe azurescens.
- Tactile enhancement - This effect is less prominent than with that of LSD or 2C-B but is still present and unique in its character. It is repeatedly described as feeling very primitive in its nature often times with the small hairs on the user's arms or legs feeling slightly itchy or even ticklish against the skin.
- Changes in felt bodily form - This effect is often accompanied by a sense of warmth or unity and usually occurs around the peak of the experience or directly after. Users can feel as if they are physically part of or conjoined with other objects. This is usually reported as feeling comfortable in its sensations and even peaceful.
- Nausea - This effect can be greatly lessened or even completely avoided if the individual has an empty stomach prior to ingestion. It is often recommended that one either refrain from eating for approximately 6 to 8 hours beforehand, or eat a light meal 3 to 4 hours before if they are feeling physically fatigued.
- Changes in felt gravity
- Excessive yawning - This effect seems to be uniquely pronounced among psilocybin and related tryptamines. It can occur to a lesser degree on LSD and very rarely on psychedelic phenethylamines like mescaline. It typically occurs in combination with watery eyes.
- Watery eyes
- Frequent urination
- Muscle contractions
- Olfactory hallucination
- Pupil dilation
- Runny nose
- Increased salivation
- Brain zaps - Although this effect is very rare, it can still occur for those susceptible to it. This component is however much less common and intense than it is with serotonin releasing agents such as MDMA.
- Seizure - This is a rare effect but can happen in a small population of those who are predisposed to them, particularly while in physically taxing conditions such as being dehydrated, undernourished, overheated, or fatigued.
- Colour enhancement - Relative to other psychedelics, this effect may appear to be more saturated.
- Pattern recognition enhancement
- Visual acuity enhancement - This effect typically occurs prominently at lower doses and becomes increasingly suppressed as one raises the dose.
- Drifting (melting, flowing, breathing and morphing) - In comparison to other psychedelics, this effect can be described as highly detailed, realistic, slow and smooth in motion and static in appearance.
- Colour shifting
- Colour tinting
- Visual haze
- After images
- Symmetrical texture repetition
- Perspective distortions
- Depth perception distortions
- Environmental orbism
- Scenery slicing
The visual geometry produced by psilocybin mushrooms can be described as more similar in appearance to that of 4-AcO-DMT, ayahuasca and 2C-E than LSD or 2C-B. It can be comprehensively described through its variations as intricate in complexity, abstract in form, organic in feel, structured in organization, brightly lit, and multicoloured in scheme, glossy in shading, soft in its edges, large in size, slow in speed, smooth in motion, rounded in its corners, non-immersive in-depth and consistent in intensity. It has a very "organic" feel and at higher dosages is significantly more likely to result in states of Level 8B visual geometry over level 8A.
Psilocybin and its various other forms produce a full range of high level hallucinatory states in a fashion that is more consistent and reproducible than that of many other commonly used psychedelics. These effects generally include:
- Internal hallucination (autonomous entities; settings, sceneries, and landscapes; perspective hallucinations and scenarios and plots) - This effect is very consistent in dark environments at appropriately high dosages. They can be comprehensively described through their variations as lucid in believability, interactive in style, new experiences in content, autonomous in controllability, geometry-based in style and almost exclusively of a personal, religious, spiritual, science-fiction, fantasy, surreal, nonsensical, or transcendental nature in their overall theme.
- External hallucination (autonomous entities; settings, sceneries, and landscapes; perspective hallucinations and scenarios and plots) - These are more common within dark environments and can be comprehensively described through their variations as lucid in believability, interactive in style, new experiences in content, autonomous in controllability, geometry-based in style and almost exclusively of a personal, religious, spiritual, science-fiction, fantasy, surreal, nonsensical or transcendental nature in their overall theme.
The cognitive effects and general head space of psilocybin is described by many as extremely relaxing, profound and stoning in style when compared to other commonly used psychedelics such as LSD or 2C-B which tend to be energetic and stimulating, it is also regarded as being significantly less clearheaded than other commonly used tryptamines such as DMT and ayahuasca.
- Emotion enhancement - This effect can be described as being more prominent, consistent and profound when compared to other traditional psychedelics such as mescaline or LSD. This can lead to strong feelings of compassion, urgency and even completely sporadic moments of intense emotional significance that can also be periodically affected by enhancement and suppression cycles.
- Empathy, affection, and sociability enhancement - This effect differs from MDMA and other entactogens in that it isn't as central to the experience, feels less forced and more natural and is experienced at a less consistent rate. The sociability enhancement in particular only occurs rarely and it appears to be more emotional.
- Language suppression - This effect can be described as a perceived inability or general unwillingness to talk aloud despite feeling perfectly capable of formulating coherent thoughts within one's internal narrative. It is much more common among inexperienced users.
- Analysis enhancement - This effect is consistent in its manifestation and outrospection dominant.
- Enhancement and suppression cycles - This can be described as constant waves of extremely stimulated and profound thinking which are spontaneously surpassed in a cyclic fashion by waves of general thought suppression and mental intoxication. These two states seem to switch between each other in a consistent loop once every 20 to 60 minutes.
- Feelings of impending doom - This effect is usually only experienced during the come up phase but typically completely passes or subsides once the primary effects begin. It should be noted that this effect is relatively consistent and normal for psilocybin and related tryptamines which is why a positive and well-informed mindset is key. Less regularly this aspect can also occur during the peak but will most often be met afterwards with sensations of euphoria, catharsis or rejuvenation.
- Cognitive euphoria
- Autonomous voice communication
- Suggestibility enhancement
- Conceptual thinking
- Thought connectivity
- Thought deceleration
- Thought loops
- Thought organization
- Confusion - This effect occurs at a higher rate than other psychedelics such as LSD or DMT. It is more commonly observed in users who are inexperienced with psilocybin, or psychedelics in general
- Novelty enhancement
- Creativity enhancement
- Déjà vu
- Increased music appreciation
- Immersion enhancement
- Memory enhancement
- Memory suppression
- Simultaneous emotions
- Personal bias suppression
- Ego replacement - Although this effect is rare and more likely to occur with certain psychedelics like DMT or ayahuasca, it can still spontaneously occur, usually with higher doses.
- Personality regression - Although this effect is rare it can still manifest spontaneously and is thought to depend primarily on the user's set and setting.
- Rejuvenation - While this component can occur spontaneously at any point, it typically follows a difficult phase of the experience, if not the entire experience itself. It is however almost always felt during the offset of a psilocybin experience and tends to slowly transition into the after effects which are generally described as positive. These positive or mindful after effects are sometimes referred to as an "afterglow" and is both common and consistent for psilocybin and related tryptamines.
- Addiction suppression
- Time distortion
- Synaesthesia - In its fullest manifestation, this is a very rare and non-reproducible effect. Increasing the dosage can increase the likelihood of this occurring, but seems to only be a prominent part of the experience among those who are already predisposed to synaesthetic states.
- Dosage independent intensity
- Cannabis - Cannabis majorly amplifies the sensory and cognitive effects of psilocybin mushrooms. This should be used with extreme caution, especially if one is not experienced with psychedelics. This interaction can also amplify the anxiety, confusion and delusion producing aspects of cannabis significantly. Those who choose to use this combination are advised to start off with only a fraction of their usual cannabis dose, and slow down the pace of their normal intake considerably.
- Dissociatives - Dissociatives can enhance the geometry, euphoria, dissociation and hallucinatory effects of psilocybin mushrooms. Dissociative-induced holes, spaces, and voids while under the influence of psilocybin can result in significantly more vivid visuals than dissociatives alone, along with more intense internal hallucinations, confusion, nausea, delusions and chances of a psychotic reaction.
- MDMA - MDMA enhances the visual, physical and cognitive effects of psilocybin. The synergy between these substances is unpredictable, and it is advised to start with lower dosages than one would take for either substance individually. The toxicity of this combination is unknown, although there is some evidence that suggests this may increase the the neurotoxic effects of MDMA.
- Alcohol - This interaction is not typically recommended due to alcohol’s ability to cause dehydration, nausea, and physical fatigue which can negatively affect an experience if taken in moderate to high dosages. This combination is, however, considered to be reasonably safe in low doses and when used responsibly, this can often "take the edge off a trip" as well as dull its psychedelic effects in a fashion somewhat similar to benzodiazepines, albeit in a more physically draining way. With psilocybin mushrooms in particular it is often recommended that the user waits until the "come down" phase if they wish to consume any alcohol due to the sometimes already nauseating and disorienting physical effects of mushrooms, especially within the first 2 - 3 hours of the experience.
- Benzodiazepines - Depending on the dosage, benzodiazepines can slightly to completely reduce the intensity of the cognitive, physical and visual effects of a psilocybin trip. They can be very efficient at largely stopping or mitigating a bad trip at the cost of amnesia and reduced trip intensity. Caution is advised when acquiring them for this purpose, however, due to the very high addiction potential that benzodiazepines possess.
- Psychedelics - When used in combination with other psychedelics, the physical, cognitive and visual effects of each substance intensify and synergize strongly with each other. The synergy between those substances is unpredictable, and for this reason, is generally not advised. If choosing to combine psychedelics, it is recommended to start with lower dosages than one would take for either substance individually.
There are currently 0 anecdotal reports which describe the effects of this compound within our experience index.
Additional experience reports can be found here:
Biological genera containing psilocybin mushrooms include Copelandia, Galerina, Gymnopilus, Inocybe, Mycena, Panaeolus, Pholiotina, Pluteus, and Psilocybe. Over 100 species are classified in the genus Psilocybe.
Risk of species confusion
As psilocybin mushrooms are capable of being harvested in nature, there is a major risk in misidentifying mushroom species and accidentally consuming poisonous, if not lethal varieties. This can be avoided by educating oneself in advance on how to properly identify the correct species of mushroom and the potential look-alike mushrooms found within one's local area. It is recommended to not learn to do this by oneself, but instead, have someone experienced in mushroom-picking as a mentor.
Dosage and preparation
The dosage of psilocybin mushrooms 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 0.5–2.0% of the dried weight of the mushroom.
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, the dried cap of the mushroom contains the most psilocybin at about 0.23%–0.90%. The mycelium contains about 0.24%–0.32%.
Psilocybe cubensis (also known as cubes) is one of the most commonly used species of psilocybin mushrooms. The doses for oral consumption for dried cubensis mushrooms are generally considered to be:
- Threshold: 0.25 - 0.50 grams
- Light: 0.5 - 1.5 grams
- Common: 2 - 3.5 grams
- Strong: 3.5 - 5 grams
- Heavy: 5 grams +
Preparation methods for this compound within our tutorial index include:
- Simple psilocybin mushroom growing technique
- Outdoor mushroom cultivation
- Mushroom chocolates
- Mushroom tea
While further research is needed to establish the utility of psilocybin and other psychedelics in treating depression, a pilot study has observed significantly decreased depression scores in terminal cancer patients six months after treatment with psilocybin. An open-label study was carried out in 2016 in the UK to investigate the feasibility, safety and efficacy of psilocybin in treating patients with unipolar treatment-resistant depression with promising results; although the study was small and involved only twelve patients, seven of those patients met formal criteria for remission one week following psilocybin treatment and five of those were still in remission from their depression at three months.
The mechanism behind this is not known as of yet, but researchers have suggested that psilocin's deactivation of the medial prefrontal cortex (mPFC) may be relevant to its antidepressant effects, as the mPFC is known to be elevated in depression and normalized after effective treatment. mPFC hyperactivity has been associated with trait rumination. Another possible factor to psilocybin's potential against depression may be that depressed patients with high levels of dysfunctional attitudes were found to have low levels of 5-HT(2A) agonism.
Toxicity and harm potential
Psilocybin is non-addictive, is not known to cause brain damage, and has an extremely low toxicity relative to dose. Similar to other psychedelic drugs, there are relatively few physical side effects associated with acute psilocin exposure. Various studies have shown that in reasonable doses in a careful context, it presents little to no negative cognitive, psychiatric or toxic physical consequences.
The toxicity of psilocybin and psilocin is extremely low. In rats, the median lethal dose (LD50) of psilocybin when administered orally is 280 milligrams per kilogram (mg/kg). Psilocybin comprises approximately 1% of the weight of Psilocybe cubensis mushrooms and so nearly 1.7 kilograms (3.7 lb) of dried mushrooms or 17 kilograms (37 lb) of fresh mushrooms would be required for a 60 kilogram (130 lb) person to reach the 280 mg/kg LD50 value of rats. Based on the results of animal studies, the lethal dose of psilocybin has been extrapolated to be 6 grams, 1000 times greater than the effective dose of 6 milligrams.
Despite its lack of physical toxicity, however, it is still strongly recommended that one use harm reduction practices if choosing to use this substance.
Tolerance and addiction potential
Psilocybin is not habit-forming with a low abuse potential and the desire to use it can actually decrease with use. Cases of abuse and addiction have been documented but are rare. Notably, there it has been claimed that is virtually no withdrawal syndrome when the chronic use of this substance is ceased.
Tolerance to the effects of psilocin are built almost immediately after ingestion. After that, it takes about 3 days for the tolerance to be reduced to half and 7 days to be back at baseline (in the absence of further consumption). Psilocin presents cross-tolerance with all psychedelics, meaning that after the consumption of psilocin all psychedelics will have a reduced effect.
Although many psychoactive substances are safe to use on their own, they can quickly become dangerous or even life-threatening when combined with other substances. The following lists some known dangerous combinations, but may not include all of them. A combination that appears to be safe in low doses can still increase the risk of injury or death. Independent research should always be conducted to ensure that a combination of two or more substances is safe to consume. Some interactions listed have been sourced from Tripsit.
- Tramadol - Tramadol lowers the seizure threshold and psychedelics may act as triggers for seizures, particularly in those who are predisposed to them.
- Stimulants - Stimulants affect many parts of the brain. Combined with psychedelics, stimulation can turn into uncontrollable anxiety, panic, thought loops and paranoia. This interaction may cause elevated risk of psychosis.
- Lithium - Lithium is often used as treatment for bipolar disorder. It may possibly cause elevated risk of seizures and psychosis due to its glutaminergic and GABAergic effects.
Internationally, psilocybin (but not psilocybin mushrooms) is a Schedule I drug under the Convention on Psychotropic Substances.
"The cultivation of plants from which psychotropic substances are obtained is not controlled by the Vienna Convention. . . . Neither the crown (fruit, mescal button) of the Peyote cactus nor the roots of the plant Mimosa hostilis nor Psilocybe mushrooms themselves are included in Schedule 1, but only their respective principals, mescaline, DMT, and psilocin."
- Austria: Psilocybin containing mushrooms are illegal to possess in dried form, to sell and to offer, give or get somebody under the SMG (Suchtmittelgesetz Österreich). It is illegal to grow them with the intention of "producing psychotropic substances" (as psilocin and psilocybin) mentioned in BGBl. III Nr. 148/1997 .
- Brazil: Possession, production and sale is illegal as it is listed on Portaria SVS/MS nº 344, but mushrooms fall under religious use laws.
- British Virgin Isles: The sale of mushrooms is illegal, but possession and consumption is legal.
- Bulgaria: The sale of mushrooms is illegal, but possession and consumption is legal.
- Belgium: Possession and sale of mushrooms have been illegal since 1988.
- Canada: Psilocybin and psilocin are illegal to possess, obtain or produce without a prescription or license as they are Schedule III under the Controlled Drugs and Substances Act.
- Czech Republic: The distribution (including sale) of mushrooms is illegal, but consumption is legal. The possession of over 40 hallucinogenic caps is considered a crime if they contain more than 50mg of psilocin or the corresponding amount of psilocybin. The possession of more than 40g of hallucinogenic mycelium is considered a crime. If these limits are not exceeded, the act is considered a minor offense and a fine of up to 15 thousand CZK may be imposed.
- Cyprus: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Denmark: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Finland: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Germany: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Greece: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Ireland: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Iceland: The sale of Psilocybin mushrooms is illegal, but possession and consumption is legal.
- Japan: Psilocybin mushrooms are illegal to possess, grow, sale, and consume.
- Latvia: Hallucinogenic mushrooms, psilocin and psilocybin are Schedule I controlled substances.
- Mexico: The possession, growth, sale and consumption of mushrooms is illegal. Rules are relaxed regarding religious use however.
- The Netherlands: The possession, growth, sale and consumption of mushrooms is illegal. However, due to a legal loophole, psilocybin truffles can be legally possessed, grown, sold and consumed.
- New Zealand: Psilocybin is a Class A substance.
- Norway: Possession, growth, sale and consumption of mushrooms is illegal. Spores, even though not containing psilocybin, are also illegal.
- Sweden: Sveriges riksdag added psilocybin mushrooms to schedule I ("substances, plant materials and fungi which normally do not have medical use") as narcotics in Sweden as of Aug 1, 1999, published by Medical Products Agency.
- Turkey: The possession, growth, sale and consumption of mushrooms is illegal.
- United Kingdom: According to the 2005 Drugs Act, fresh and prepared psilocybin mushrooms are Class A.
- United States: Psilocybin and psilocin are Schedule I drugs under the Controlled Substances Act of 1970. This means it is illegal to manufacture, buy, possess, process, or distribute without a license from the Drug Enforcement Administration (DEA).
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