The term hallucinogen refers to many different drugs, which are often called “psychedelic” drugs. While the effects of these drugs vary widely, all change the way people see, hear, taste, smell or feel, and affect mood and thought. At high doses, all may cause a person to hallucinate, or see, hear or feel things that aren’t really there.
Most of the hallucinogens used in North America belong to one of these six categories:
Some hallucinogens come from mushrooms (psilocybin), cacti (mescaline) and other plants (cannabis, salvia). Of these, cannabis and psilocybin are almost always used in their natural form. Although LSD is used only in a synthesized form, a related drug, LSA, is found in nature. Other hallucinogens, such as MDMA and ketamine, are created in laboratories.
Hallucinogens have been used since ancient times in religion, medicine, magic and prophecy. In the 1960s and 70s, hallucinogen use became a symbol of the counter-culture among young people in North America and Europe. In the 1990s, hallucinogen use was linked to the “rave” scene.
A 2007 survey of Ontario students in grades 7 to 12 reported that:
A 2004 survey of Canadians (aged 15+) reported that:
How hallucinogens make you feel depends on:
Hallucinogens cause mostly psychoactive, or mind-altering, effects, which can be mild to intense. These effects vary from drug to drug, from person to person, from one drug-taking episode to the next, and can even change dramatically within one time of use. Effects can range from ecstasy to terror, from mild distortion of the senses to full hallucinations (where people believe that drug-induced visions or other perceptions are real).
Different types of hallucinogens produce different effects; for example:
LSD produces a kaleidoscope of visual patterns and changes perception. People who take LSD usually know that the hallucinations are not real; however, the effects can appear real.
Ecstasy enhances mood and produces feelings of empathy and intimacy.
Ketamine causes an out-of-body feeling, which may be pleasant or terrifying.
Salvia causes intense, short-lived hallucinogenic effects, such as smelling sounds or hearing colours.
The effects of some hallucinogens, such as LSD, last for hours, while others, such as salvia, last only a short time.
Most people who use hallucinogens do so occasionally. Repeated use of hallucinogens such as LSD or ecstasy leads to tolerance, where the drug has reduced or no effect. Sensitivity to the drug returns if the person stops using it for a period of time, and then starts again. Stopping use of hallucinogens does not usually cause symptoms of withdrawal. However, people can develop psychological dependence, in which they feel they need the drug.
Most of these drugs are illegal and unregulated, and may include toxins, or not even contain the drug they are sold as. For example, drugs sold as ecstasy are usually not pure MDMA, and have been found to contain other drugs, such as methamphetamine. Drugs sold as mescaline are almost always something else.
Hallucinogens affect perception and behaviour. Taking them may cause people to become disoriented, have poor judgment and take risks.
Many hallucinogens can have very unpleasant or toxic effects (e.g., jimsonweed, deadly nightshade). Hallucinogenic plants can be mistaken for other toxic or lethal plants, for example, mushrooms.
Although research is scarce, taking hallucinogens during pregnancy may affect the development of the baby, and increase the chance of miscarriage.
Hallucinogen use may, on rare occasions, result in “flashbacks,” or replays of the drug experience, days, weeks or even years after the drug was taken. Some people who take hallucinogens feel depressed or anxious long after they took the drug.
Copyright © 2004, 2009 Centre for Addiction and Mental Health
Your donation moves us closer to a future where no one is left behind.
Keep your finger on our pulse – latest CAMH news, discoveries and ways to get involved delivered to your inbox.
Please select a newsletter
Please complete the following:
We look forward to keeping you informed, inspired and involved in all things CAMH.
Every donation moves us closer to a future where no one is left behind.