| Routes of|
|CompTox Dashboard (EPA)|
|Chemical and physical data|
|Molar mass||270.225 g·mol−1|
|3D model (JSmol)|
Baeocystin is a zwitterionic alkaloid and analog of psilocybin. It is found as a minor compound in most psilocybin mushrooms together with psilocybin, norbaeocystin, aeruginascin, and psilocin.  Baeocystin is an N-demethylated derivative of psilocybin, and a phosphorylated derivative of 4-HO-NMT (4-hydroxy-N-methyltryptamine). The structures at right illustrate baeocystin in its zwitterionic form.
Baeocystin was first isolated from the mushroom Psilocybe baeocystis ,  and later from P. semilanceata ,  Panaeolus renenosus , Panaeolus subbalteatus , and Copelandia chlorocystis .  It was first synthesized by Troxler et al. in 1959. 
Little information exists with regard to human pharmacology, but in the book Magic Mushrooms Around the World, author Jochen Gartz reports being aware of a study in which "10 mg of baeocystin were found to be about as psychoactive as a similar amount of psilocybin."  Gartz also reported in a research paper that a self-administered assay of 4 mg of baeocystin caused "a gentle hallucinogenic experience". 
While Gartz describes experiencing a "gentle hallucinogenic experience" from baeocystin, this could not be replicated in a mouse model in a 2019 study which found no evidence that baeocystin produces any hallucinogenic effects.  Researchers compared psilocybin which is a known hallucinogen to baeocystin by using the mouse head-twitch response. Upon comparison, baeocystin was indistinguishable from saline solution, indicating "...baeocystin alone would likely not induce hallucinogenic effects in vivo". This does contrast however with the human experiences mentioned above, although high quality data is scarce.
Psilocybin is a naturally occurring psychedelic prodrug compound produced by more than 200 species of fungi. The most potent are members of genus Psilocybe, such as P. azurescens, P. semilanceata, and P. cyanescens, but psilocybin has also been isolated from about a dozen other genera. Psilocybin is itself biologically inactive but is quickly converted by the body to psilocin, which has mind-altering effects similar, in some aspects, to those of lysergic acid diethylamide (LSD), mescaline, and dimethyltryptamine (DMT). In general, the effects include euphoria, visual and mental hallucinations, changes in perception, distorted sense of time, and perceived spiritual experiences. It can also cause adverse reactions such as nausea and panic attacks.
Psilocybe cubensis is a species of psilocybin mushroom of moderate potency whose principal active compounds are psilocybin and psilocin. Commonly called shrooms, magic mushrooms, golden halos, cubes, or gold caps, it belongs to the fungus family Hymenogastraceae and was previously known as Stropharia cubensis. It is the best-known psilocybin mushroom due to its wide distribution and ease of cultivation. This mushroom being optimal for home cultivation specifically, as was suggested in the 1970s, is primarily what led to cubensis being the psilocybin mushroom species most common on the black market as a street drug.
Psilocybin mushrooms, commonly known as magic mushrooms, are a polyphyletic informal group of fungi that contain psilocybin which turns into psilocin upon ingestion. Biological genera containing psilocybin mushrooms include Psilocybe, Panaeolus, Inocybe, Pluteus, Gymnopilus, and Pholiotina. Psilocybin mushrooms have been and continue to be used in indigenous New World cultures in religious, divinatory, or spiritual contexts. They are also used as recreational drugs. They may be depicted in Stone Age rock art in Africa and Europe, but are most famously represented in the Pre-Columbian sculptures and glyphs seen throughout North, Central and South America.
Psilocybe is a genus of gilled mushrooms, growing worldwide, in the family Hymenogastraceae. Most or nearly all species contain the psychedelic compounds psilocybin and psilocin.
Psilocybe semilanceata, commonly known as the liberty cap, is a species of fungus which produces the psychoactive compounds psilocybin, psilocin and baeocystin. It is both one of the most widely distributed psilocybin mushrooms in nature, and one of the most potent. The mushrooms have a distinctive conical to bell-shaped cap, up to 2.5 cm (1 in) in diameter, with a small nipple-like protrusion on the top. They are yellow to brown, covered with radial grooves when moist, and fade to a lighter color as they mature. Their stipes tend to be slender and long, and the same color or slightly lighter than the cap. The gill attachment to the stipe is adnexed, and they are initially cream-colored before tinting purple to black as the spores mature. The spores are dark purplish-brown in mass, ellipsoid in shape, and measure 10.5–15 by 6.5–8.5 micrometres.
Psilocin is a substituted tryptamine alkaloid and a serotonergic psychedelic substance. It is present in most psychedelic mushrooms together with its phosphorylated counterpart psilocybin. Psilocin is a Schedule I drug under the Convention on Psychotropic Substances. Acting on the 5-HT2A receptors, psilocin modulates the production and reuptake of serotonin. The mind-altering effects of psilocin are highly variable and subjective and resemble those of LSD and DMT.
Norbaeocystin is a psilocybin mushroom alkaloid and analog of psilocybin. It is found as a minor compound in most psilocybin mushrooms together with psilocin, psilocybin, aeruginascin, and baeocystin, from which it is a derivative.
Psilocybe tampanensis is a very rare psychedelic mushroom in the family Hymenogastraceae. Originally collected in the wild in a sandy meadow near Tampa, Florida, in 1977, the fungus would not be found in Florida again until 44 years later. The original Florida specimen was cloned, and descendants remain in wide circulation. The fruit bodies (mushrooms) produced by the fungus are yellowish-brown in color with convex to conic caps up to 2.4 cm (0.9 in) in diameter atop a thin stem up to 6 cm (2.4 in) long. Psilocybe tampanensis forms psychoactive truffle-like sclerotia that are known and sold under the nickname "philosopher's stones". The fruit bodies and sclerotia are consumed by some for recreational or entheogenic purposes. In nature, sclerotia are produced by the fungus as a rare form of protection from wildfires and other natural disasters.
Panaeolus cinctulus, syn. Panaeolus subbalteatus, commonly known as the banded mottlegill, weed Panaeolus or subbs is a very common, widely distributed psilocybin mushroom. According to American naturalist and mycologist David Arora, Panaeolus cinctulus is the most common psilocybin mushroom in California.
O-Acetylpsilocin is a semi-synthetic psychoactive drug that has been suggested by David Nichols to be a potentially useful alternative to psilocybin for pharmacological studies, as they are both believed to be prodrugs of psilocin. However, some users report that O-acetylpsilocin's subjective effects differ from those of psilocybin and psilocin. Additionally, some users prefer 4-AcO-DMT to natural psilocybin mushrooms due to feeling fewer adverse side effects such as nausea and heavy body load, which are more frequently reported in experiences involving natural mushrooms. It is the acetylated form of the psilocybin mushroom alkaloid psilocin and is a lower homolog of 4-AcO-MET, 4-AcO-DET, 4-AcO-MiPT and 4-AcO-DiPT.
Ethocybin is a homologue of the mushroom alkaloid psilocybin, and a semi-synthetic psychedelic alkaloid of the tryptamine family. Effects of ethocybin are comparable to those of a shorter LSD or psilocybin trip, although intensity and duration vary depending on dosage, individual physiology, and set and setting.
Psilocybe baeocystis is a psilocybin mushroom of the family Hymenogastraceae. It contains the hallucinogenic compounds psilocybin, psilocin and baeocystin. The species is commonly known by various names such as bottle caps, knobby tops, blue bells, olive caps.
Conocybe is a genus of mushrooms with Conocybe tenera as the type species and at least 243 other species. There are at least 50 different species in North America.
Pholiotina cyanopus is a species of fungus that contains psychoactive compounds including psilocybin and the uncommon aeruginascin. Originally described as Galerula cyanopus by American mycologist George Francis Atkinson in 1918. It was transferred to Conocybe by Robert Kühner in 1935 before being transferred to Pholiotina by Rolf Singer in 1950. A 2013 molecular phylogenetics study found it to belong to a group of species currently assigned to Pholiotina that are more closely related to Galerella nigeriensis than to Pholiotina or Conocybe. It is likely that it will be moved to a different genus in the future, but this has not happened yet.
Panaeolus cyanescens is a mushroom in the Bolbitiaceae family. Panaeolus cyanescens is a common psychoactive mushroom and is similar to Panaeolus tropicalis.
Aeruginascin or N,N,N-trimethyl-4-phosphoryloxytryptamine is an indoleamine derivative which occurs naturally within the mushrooms Inocybe aeruginascens and Pholiotina cyanopus, and Psilocybe cubensis. Aeruginascin is the N-trimethyl analogue of psilocybin. It is closely related to the frog skin toxin bufotenidine (5-HTQ), a potent 5-HT3 receptor agonist, but the aeruginascin metabolite 4-HO-TMT shows strong binding at the 5-HT2 receptors similar to psilocin. The first scientific literature about the pharmacological effects of aeruginascin is from a study published by Gartz in 1989. Across 23 analyzed cases of accidental hallucinogenic mushroom poisonings, people who had ingested the mushroom Inocybe aeruginascens reported only euphoric experiences. This is in contrast to the slight and in some cases extremely dysphoric experiences reported from the accidental ingestion of non aeruginascin containing mushrooms (containing solely psilocybin and psilocin).
Panaeolus microsporus is a species of mushroom in the Bolbitiaceae family. It is a psychoactive species of the Panaeolus genus, containing alkaloids like psilocybin and psilosin. All Panaeolus species produce serotonin and serotonin derivatives.
Psilocybe serbica is a species of mushroom in the family Hymenogastraceae. The mushroom contains the psychotropic compounds psilocybin and psilocin, and also related tryptamine alkaloids baeocystin, norbaeocystin, and aeruginascin. It is closely related to Psilocybe aztecorum. It was reported as new to science by Meinhard Moser and Egon Horak in 1969. Molecular analysis published in 2010 has shown that P. serbica is the same species as Psilocybe bohemica described by Šebek in 1983, Psilocybe arcana described by Borovička and Hlaváček in 2001, and Psilocybe moravica by Borovička in 2003. Psilocybe serbica is common in Central Europe.