Citation metadata

Date: Oct. 1, 2016
Publisher: Gale, a Cengage Company
Document Type: Drug overview; Topic overview
Length: 4,487 words

Document controls

Main content

Full Text: 

Official Names: Psilocybin (sill-o-SIGH-bin), mushrooms of the Psilocybe, Panaeolus, and Conocybe genera
Street Names: boomers, caps, cubes, fungus, hippy flip (with ecstasy), liberty caps, MX missile (with ecstasy), magic mushrooms, Mexican mushrooms, mushies, mushrooms, psychedelic mushrooms, psilocydes, purple passion, shrooms, sillies, silly putty, simple Simon
Drug Classification: Schedule I, hallucinogen

What Kind of Drug Is It?

Many species of mushroom throughout the world produce mind-altering effects when eaten. The mushrooms in the genus Psilocybe are perhaps best known for their psychedelic properties. Called "magic mushrooms," or just "shrooms," psilocybin-containing mushrooms can produce a wide variety of experiences for the user, from extreme mood swings to visions of bright colors, even to a feeling of time standing still.

For thousands of years, Native American priests used psilocybin in religious ceremonies, under carefully controlled conditions. In the last half of the twentieth century, however, "shrooms" gained popularity as a recreational drug--a drug used solely to get high, not to treat a medical condition. Magic mushrooms remained popular in the early 2000s, even though they are illegal.

In the 1950s and early 1960s, scientists conducted research on psilocybin, hoping that it could help people with schizophrenia and other mental disorders. Schizophrenia is a severe mental disorder that makes it difficult for people to behave normally and function adequately in their everyday lives. Some researchers thought psilocybin might even make criminals less likely to commit violence.

None of this research proved to have positive results. In fact, the naturally occurring chemicals in Psilocybe mushrooms have unpredictable effects, even on people who use them frequently. Psilocybin has no medical uses, and the U.S. government has named it a Schedule I controlled substance. As such, these mushrooms carry the highest penalties for users and dealers.


About 5,000 species of mushrooms have been discovered and named by scientists. Of these, about 100 species contain psilocybin. How and why did these plants evolve this way? Most botanists think the mind-altering chemicals serve as a defense for the plant. Animals eat the mushrooms, have a bad reaction to the psilocybin, and avoid these types of mushrooms after that.

Experimentation and Religious Ritual

Throughout history, human beings have experimented with altering their mental states. In both the Eastern and Western Hemispheres, in fact, cults of hallucinogen use can be traced back many thousands of years. The ancient Vedas (texts of India) mention a bright red mushroom, believed to be Amanita muscaria, that could be used to connect with the gods. The Greeks made a hallucinogen from a mold called ergot. In the Americas, the indigenous, or native, peoples created religious rituals around mushrooms, toad venom, and other plants that could bring on a variety of psychedelic, or mind-altering, experiences.

Psilocybin use in the Americas can be traced back to the Aztecs, although they were probably not the first to use it. Archaeologists found a statue dating to the year 100 that shows a shaman, or medicine man, seated under a mushroom. Most indigenous cultures approached magic mushroom use with great care. They chose only certain candidates for the experience and guided those individuals through the process. Mushrooms were used only on the most sacred holidays and only by the shamans and their students. Native cultures believed that psilocybin helped them talk to the gods, tell the future, and communicate with the spirits of the dead.

Although psilocybin use is illegal in the United States, some Native American groups are allowed to continue to use Psilocybe mushrooms in their religious ceremonies.

Europeans Ban It

When Europeans began settling the New World in the 1500s, they brought Christianity with them. Spanish, French, and British missionaries hoped to convert the native peoples to their religion. They viewed the use of psilocybin as being contrary to Christian practices, and they severely punished Native Americans who used the drug. However, mushroom use survived underground as the indigenous peoples conducted their rituals in secret.

In 1957, an amateur mycologist named R. Gordon Wasson (1898-1986) published a story about his experiences with psilocybin use among the Native Americans of Mexico. The story ran in 1958 in Life, one of the most popular monthly magazines of that era.

Dangers Lead to Restricted Use

The timing of Wasson's magazine article was important. A new, rebellious generation of young Americans had emerged after World War II (1939-1945). They were eager to try mind-altering drugs. Serious scientists such as Swiss chemist Albert Hofmann (1906-2008) were busy synthesizing hallucinogens in the laboratory. Hofmann isolated psilocybin and found a way of making it without using the mushrooms. He also discovered LSD (lysergic acid diethylamide). (An entry on LSD is available in this encyclopedia.) Some people believed that substances such as psilocybin might be fun to try. Others thought the substance might be an effective treatment for mental illness. Still others, including the U.S. government, began experiments with mind control using hallucinogens.

What all of these people discovered was that hallucinogens such as psilocybin and LSD do not act predictably. A person's reaction to the substance depends on many factors, including family history of mental illness and the expectations that the person has when taking the drug. Even people who have taken psilocybin many times could suddenly have a "bad trip"--an intense negative experience where the user has hallucinations or visions or other perceptions of things that are not really present. Bad trips create a heightened sense of danger; paranoia or abnormal feelings of suspicion and fear; and panic.

Researchers abandoned psilocybin for use with mental patients and criminals. Even so, its use as a recreational drug increased among young people in the 1960s. In 1965, President Lyndon Johnson (1908-1973) recommended altering the existing drug laws to make all hallucinogens illegal. The law was passed as the Drug Abuse Control Amendment (DACA) of 1965.

More Restrictions

The DACA bill, however, did not name psilocybin or its related compound, psilocin. Therefore, use of these two substances remained legal for another three years. In 1968, psilocybin and psilocin were specifically made illegal. Keeping "magic mushrooms" off the black market has never been easy, though.

The mushrooms grow wild in the Pacific Northwest and in the warmer regions of the South--especially Florida. Trained spotters can find them. A network of black market growers exchange spores (seeds), which are still legal. They grow mushrooms in homes and greenhouses. Even today, several hundred arrests are made each year, in every part of the United States, for possession of Psilocybe mushrooms.

Milder in their effects than LSD, "magic mushrooms" appeared on the rave scene in the 1990s and enjoyed a brief surge in popularity. According to the "2003 National Survey on Drug Use and Health (NSDUH)," however, overall hallucinogen use was down in the early part of the twenty-first century in the United States. Various personal accounts of psilocybin use are available on the Internet. Such testimonies document both the "enjoyable" aspects of the drug and its ability to cause panic and frightening episodes.

What Is It Made Of?

Psilocybin's full chemical name is phosphorylated 4-hydroxydimethyltryptamine (FOSS-FOR-ih-lay-tid 4-high-DROK-see-dy-meth-uhl-TRIP-tuh-meen). It is a naturally occurring compound found in mushrooms of the genus Psilocybe, the genus Panaeolus, and the genus Conocybe. About 100 species contain psilocybin. The most widely used psilocybin-containing mushrooms in the United States are Psilocybe mexicana, Psilocybe cyanescens (also known as "wavy caps"), and Psilocybe cubensis.

Within the mushroom, psilocybin is an indole alkaloid. It is often accompanied by other alkaloid compounds with mind-altering properties, including psilocin, baeocystin, and norbaeocystin. The amounts of these compounds vary widely from species to species and even from one individual mushroom to another. The psilocybin content of a single mushroom can range from 0.03 percent to 1.3 percent of the weight of the mushroom.

Almost all mushrooms are composed of 80 to 90 percent water. Drying the mushrooms and removing the water concentrates the psilocybin. Therefore, dried mushrooms have a higher potency, or strength, than fresh mushrooms. Whether consumed fresh or dried, however, the mushrooms have a strong, unpleasant, dirt-like flavor that can produce nausea.

In the 1950s, scientists produced a synthetic version of psilocybin in the form of powder and pills. These products are no longer available. They would be highly dangerous if used recreationally because of their potency.

How Is It Taken?

Archaeologists have found evidence that ancient native cultures took psilocybin by inserting tubes into their rectums and having liquid preparations poured through the tubes. Modern people simply chew and eat small pieces of the dried mushroom. Since the mushrooms have an unpleasant taste, users sometimes pour boiling water over the mushroom, mix in honey or sugar, and drink the "tea" that results. The mushrooms are also eaten in combination with honey or other more pleasant-tasting foods. The most dedicated users chew the foul-tasting mushrooms longer, knowing that the psilocybin will reach the bloodstream faster through the tissues of the mouth than it will if swallowed and digested.

Typically, psilocybin is not injected, smoked, or snorted. Users of magic mushrooms tend to seek a more natural experience and do not resort to needles or other drug paraphernalia.

Are There Any Medical Reasons for Taking This Substance?

Psilocybin and other hallucinogens have been studied for use in psychotherapy and the treatment of mental illness. At one time researchers thought that psilocybin might help to make criminals less violent. In a study conducted between 1961 and 1963 by Professor Timothy Leary (1920-1996) and Ralph Metzner (1936- ), this theory was put to the test. The researchers attempted to prove that psilocybin could be used to reform criminals at the Massachusetts Correctional Institute in Concord.

As part of the study, a group of inmates was given two high doses of psilocybin over six weeks, along with several sessions of therapy. It was hoped that in the drug-induced state, inmates would gain new insights about themselves, understand what they wanted out of life, and decide to leave the life of crime. The real test came when the inmates were released from prison. The researchers found that their test subjects had the same rate of returning to prison for new crimes as the inmates who were not part of the study. In addition, the test inmates ended up having more parole violations than the average parolee.

Other researchers looked into whether psilocybin might lessen the symptoms of obsessive-compulsive disorder (OCD), since some users reported that the drug eased their compulsions. This had not been widely studied as of 2005. Since the effects of psilocybin vary so much from dose to dose, and since so little is known about how it actually works in the brain, it is not considered a good candidate for treatment of any illness.

Usage Trends

Psilocybin has never been widely used, but it has never been ignored, either. From the days in the 1500s when Spanish missionaries tried to stamp out its use among the indigenous peoples of the Americas, to the 1957 Life magazine article that popularized "magic mushrooms," people have experimented with psilocybin. Mushrooms continued to be used in the 1960s and early 1970s as part of the "hippie era," and their effects were praised by such well-known drug gurus as Timothy Leary and Richard Alpert (better known as Ram Dass; 1931- ). In fact, Leary described his first experience with magic mushrooms as a religious experience.

A study conducted by Australia's Bond University attempted to corelate the personality traits of hallucinogen abusers compared with drug abusers using other types of drugs. The researchers compared subjects in both Israel and Australia in order to eliminate the possibility of cultural variation, and reported that psychedelic users scored significantly higher on mystical beliefs (e.g., oneness with God and the universe) and life values of spirituality and concern for others than the other groups, and lower on the value of financial prosperity, irrespective of culture of origin,

By the end of the 1980s, psilocybin use had dropped considerably. Some drug users were reluctant to try magic mushrooms because various species of mushrooms are poisonous. It can be hard to tell which ones are poisonous and which ones are not. Also, reports of fatalities--not from overdose but from bizarre behavior while under the influence--have helped to curb the desire for magic mushrooms.

The most recent data on use of psilocybins in the general U.S. population comes from the National Survey on Drug Use and Health (NSDUH) of the Substance Abuse and Mental Health Services Administration (SAMHSA) for 2013. According to the study, 22,850,000 Americans reported that they had used psilocybin at least once during their lifetime, and increase of about 10 percent over the previous year (2012). The largest percentage of those users were in the age group 26 years and over (19,209,000), followed by those in the age group 18 to 25 (3,347,000). Few additional data on psilocybin use in the United States are available because, as an informational leaflet from the National Institute on Drug Abuse says, "It is difficult to gauge the extent of use of these hallucinogens because most data sources that quantify drug use exclude these drugs."

Legal Use

Some people can use psilocybin legally. These include certain Native American groups who use the mushrooms for religious reasons. In addition, due to a legal loophole, psilocybin mushrooms were sold legally in Japan up until mid-2002. Vendors could sell the shrooms for "non-consumptive" uses. Shop owners peddled them as "decorations" and for "aroma therapy," but once the mushrooms were purchased, buyers often did as they pleased with them. According to BBC News, in 2002 the Japanese government put a stop to all buying and selling of magic mushrooms. "[T]hose found in possession of magic mushrooms could face up to seven years in prison," which is the same sentence given for those convicted of cocaine possession.

Effects on the Body

Psilocybin enters the central nervous system and disrupts the levels of serotonin in the brain and body. Serotonin is an important neurotransmitter. In normal balance, serotonin controls moods, regulates anxiety, and helps the brain process information from the five senses. It also influences digestion, blood flow, and other organ performance. When a user eats a psilocybin-containing mushroom, the psilocybin activates serotonin receptors in the place of serotonin. This brings on changes in perception and mood swings. It can cause tremors, nausea, and sleeplessness.

A Strange and Risky Experience

A psilocybin user will typically eat 1 to 5 grams of the drug, or the equivalent of two to four mushrooms. If the user chews on the mushrooms or holds them in his or her mouth for several minutes, the effects of the drug begin in about ten minutes. Eating and swallowing the mushrooms delay the effects for about thirty to forty-five minutes. When the psilocybin passes through the digestive system and into the liver, it is changed into psilocin, the active tryptamine compound. The psilocin moves through the bloodstream to the brain.

At the onset of a psilocybin experience, the user may feel a tingling throughout the body. Some people experience anxiety at this point. As the drug's effects heighten over the next two hours, the user may undergo extreme mood swings, feeling euphoria and an urge to laugh, or feeling frightened or deeply depressed. Changes occur in all of the senses. Users might "see" sounds or "taste" colors. Vision is altered. Although the user does not see things that aren't there--the true meaning of "hallucination"--the user will perceive that colors become more brilliant, that boundaries are distorted, and that his or her own body has changed significantly. Sometimes these distortions of vision become permanent, and people discover that they have become overly sensitive to all movement and to the behavior of light.

The drug alters the sense of time as well. Users report feeling that time is standing still, or moving backward. They may feel that the boundaries between their bodies and the earth have dissolved. This loss of sense of self is called "ego dissolution." Researchers think it plays an important role in the religious uses of the drug, but it can be frightening for people who use psilocybin just to get high.

Since serotonin plays a role in the thinking process, users on a psilocybin trip may experience distortions in thinking. These can be positive, leading to a sort of religious ecstasy and sense of communication with higher powers. The distortion can just as easily be negative, leading to panic, fear of self and others, and misunderstanding when others try to help. Whether the sensations are pleasant or nightmarish, little can be done to ease them. The user must simply wait for the drug to exit the brain. This usually occurs within two to six hours.

Psilocybin Dangers and Mental Disorders

Psilocybin users have reported that, after using mushrooms, they often experience mood swings over the following days. People who suffer from schizophrenia or other mood disorders can trigger lasting episodes of mental illness by taking psilocybin. Anyone with a family history of schizophrenia or other psychiatric conditions should never take psilocybin.

Scientists note that psilocybin is not habit-forming, but it does quickly produce tolerance. This increases the danger of panic reaction and also introduces the danger of overdose. While not fatal, overdoses of psilocybin can bring on mental illness in otherwise healthy people. Psilocybin may also damage the heart.

Psilocybin has been linked to flashbacks, which occur when a user re-lives experiences of a drug trip after the drug has worn off. Flashbacks are more common in people who suffered from mental disorders before they took the drug.

Some people are allergic to psilocybin. For these people, eating "magic mushrooms" can lead to: 1) coma--a state of unconsciousness from which a person cannot be aroused by noise or other stimuli; 2) convulsions--the twitching of limbs and the involuntary contracting of muscles while in a state of unconsciousness; and 3) seizures--brain disturbances that cause loss of consciousness and uncontrolled movements in the limbs and tongue. For young children, a single dose of psilocybin can cause fatal heart problems, seizures, and coma.

Reactions with Other Drugs or Substances

One of the greatest dangers of psilocybin use is the possibility that the mushrooms in question are not Psilocybe at all. Drug dealers sometimes take ordinary supermarket mushrooms and inject them with LSD, which is far stronger than psilocybin. Mushroom hunters can misidentify the mushrooms in the wild and pick poisonous mushrooms instead. Even an outdoor plot that is mostly Psilocybe can contain random mushrooms of other types.

Some drugs, both legal and illegal, increase the effects of psilocybin. These include monoamine oxidase inhibitors (MAOIs), usually prescribed for depression. Ecstasy (MDMA) will also intensify the effects of psilocybin. LSD is very similar to psilocybin, only far more powerful. Combining the two can cause rapid heartbeat and panic attacks. Serious side effects may also occur when psilocybin is taken with alcohol; opium-based drugs such as heroin or OxyContin; or amphetamines. Over-the-counter drugs containing dextromethorphan should also be avoided by psilocybin users. (Entries on alcohol, amphetamines, dextromethorphan, ecstasy [MDMA], heroin, LSD [lysergic acid diethylamide], oxycodone, and over-the-counter drugs are also available in this encyclopedia. Information on MAOIs is available in the antidepressants entry.)

Treatment for Habitual Users

Psilocybin is not habit-forming, but frequent users develop a tolerance to its effects. Tolerance is when a user needs more and more of the drug to achieve the same result. This tolerance will decrease over time, so most users space their use of psilocybin so that they will not become tolerant to its effects.

Long-term use of psilocybin can cause mental and physical changes related to serotonin levels in the brain and body. These can include mood swings, tremors, digestive problems, and eventually, seizures and coma. As with other hallucinogens, the longer the period of use, the more difficult normal life becomes when the drug is discontinued.

Abusers of hallucinogens can find help with groups such as Narcotics Anonymous, where they can meet and talk with other recovering drug abusers. Narcotics Anonymous is an international nonprofit organization with a telephone hotline, regular meetings in most cities and towns across the United States, and a "buddy system" that teams new members with older members who have been successful at beating addiction. Recovering drug users are encouraged to end friendships and change lifestyle habits that led to the drug use. With a non-addictive substance such as psilocybin, this transition can be made fairly easily.

Emergency Visits

Most of the hospital emergency room visits related to psilocybin use involve panic attacks brought on by hallucinations or distortions in thinking. There is no known antidote to psilocybin, so hospital staff will typically try to calm the patient down with medications such as sedatives. They will also try to reassure the patient that the hallucinations will wear off and things will return to normal. The symptoms usually go away within six hours.


Psilocybin is not as strong as LSD, is not habit-forming, and is a product of nature. However, it is still hazardous. Although the drug rarely produces a dangerous overdose situation, it does produce, regularly, a state of mind that is out of touch with reality. Users do not think clearly. Their ability to move is impaired. This can--and does--lead to accidents.

Before magic mushrooms were banned in Japan, a writer for the Chicago Tribune studied the legal trade of such shrooms in Japan in 2001. Vendors could sell mushrooms containing psilocybin as long as they did not sell them as food. Some people in Japan bought the mushrooms and ate them anyway. The Tribune documented two Japanese deaths related to psilocybin--one of them being a man who jumped off a building while high on the substance. The Japanese government took steps to ban the substance in 2002 after the number of deaths linked to the mushrooms climbed significantly.

Other incidents involved American tourists in Mexico who jumped off cliffs, thinking they could fly, after ingesting fresh Psilocybe mushrooms. Psilocybin users may become paranoid and attack family members and health care workers. Medical literature documents the fact that psilocybin overdose can cause heart attacks.

The Law

In the United States, psilocybin and psilocin--the active ingredients in "magic mushrooms"--are Schedule I controlled substances. It is against the law to possess these mushrooms, either fresh or dried. It is not against the law to possess or sell the spores from the mushrooms, as these do not contain psilocybin. However, once the spores are planted and the young fungi begin to develop (called the "mycelium stage"), this level of growth is deemed illegal. As soon as psilocybin can be detected in the mushrooms, they become controlled substances.

As of 2005, California was the only state to have enacted laws making it illegal to possess or sell spores that develop into psychedelic mushrooms.

It is difficult to regulate a naturally occurring substance like a mushroom. Psilocybe mushrooms grow wild in many parts of the United States, and people do hunt for them. This can be dangerous for several reasons: 1) If caught with the mushrooms, people can be arrested and prosecuted; 2) Mushrooms that resemble Psilocybe are poisonous; 3) Some mushroom hunters get lost in the wilderness and have to be rescued by police and emergency rescue staff.

As a Schedule I substance, psilocybin carries the highest penalties for possession and sale. Users can lose driver's licenses and federal college loans. They may also face stiff fines and even jail time for a first offense. Repeat offenders commonly wind up in prison.

The only people who can legally use magic mushrooms are certain Native American groups who consider the fungi central to their religious beliefs. They continue to use the mushrooms as their ancestors did in various rituals and take steps to provide a safe environment for that use.

Key Terms

the ability to produce hallucinations or other altered mental states
a substance that brings on hallucinations, which alter the user's perception of reality
a person who studies mushrooms
black market
the illegal sale or trade of goods; drug dealers are said to carry out their business on the "black market"
a wild overnight dance party that typically involves huge crowds of people, loud techno music, and illegal drug use
a nitrogen-containing substance found in plants
made in a laboratory
obsessive-compulsive disorder (OCD)
an anxiety disorder that causes people to dwell on unwanted thoughts, act on unusual urges, and perform repetitive rituals such as frequent hand washing
a combination of carbon, hydrogen, nitrogen, and oxygen; it is found in the brain, blood, and stomach lining and acts as a neurotransmitter and blood vessel regulator
a substance that helps spread nerve impulses from one nerve cell to another
tryptamine compound
a crystalline chemical compound of carbon, hydrogen, and nitrogen that is made in plant and animal tissues
pronounced yu-FOR-ee-yuh; a state of extreme happiness and enhanced well-being; the opposite of dysphoria
a condition in which higher and higher doses of a drug are needed to produce the original effect or high experienced
visions or other perceptions of things that are not really present

Objects of Adoration

The Aztec culture in Mexico worshipped magic mushrooms as teonanacatl ("the flesh of the gods"). Teonanacatl use was restricted to the holiest ceremonies and given only to the high priests and their students.

Psilocybin Chronology

  • c. 9,000 bce A religious cult living in what is now the Sahara Desert creates carvings of gods shaped like mushrooms.
  • 2000-1400 bce Priests in India compile the Vedas, a series of writings that mention the use of psychedelic mushrooms in religious ceremonies. The authors call the drug Soma.
  • 100 ce Aztec artists carve statues in which gods are depicted with mushrooms.
  • 1502 A Psilocybe mushroom called teonanacatl is used by Native American priests during the coronation of the Aztec king Montezuma.
  • 1958 R. Gordon Wasson writes a story about psychedelic mushroom use for Life magazine. The story is titled "Magic Mushrooms."
  • 1958 Albert Hofmann makes the psilocybin compound in a laboratory, leading to the drug's use in treating mental disorders.
  • 1968 Psilocybin and its related compound, psilocin, are made illegal in the United States.
  • 1970 The Controlled Substances Act names psilocybin and psilocin Schedule I controlled substances.

What's in a Name?

The word psilocybin is a combination of two Greek words, psilo ("bald") and cybe ("head"). Psychedelic mushrooms are most commonly called "shrooms."

Nightmares and Terror

London Independent writer David McCandless interviewed a psilocybin user who described one of his negative experiences with the drug:

"I thought that the more mushrooms you took, the better," said Anthony Goodman. "I ended up plunging into a nightmare. Reality was disintegrating. I lost all track of time. Of what time meant. Of what my life meant. I ended up crying my eyes out."

Source Citation

Source Citation   

Gale Document Number: GALE|CV2646400047