What Are Psychedelic Drugs?

Types of psychedelic drugs

Verywell / Theresa Chiechi

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What is the most important information I should know about psychedelic drugs?

  • Psychedelic drugs can cause hallucinations and other risky effects.
  • Some psychedelics are being investigated for their therapeutic potential, but this research is in the early stages and these substances are not legally available outside of limited, experimental settings.
  • In June 2023, the FDA released draft guidance to help researchers design safe studies that will yield interpretable results to support future study and applications for psychedelics.

Psychedelic drugs are a group of substances that change or enhance sensory perceptions, thought processes, and energy levels. These substances are also known as hallucinogenic drugs or simply hallucinogens. They come in different forms, ranging from chemicals such as LSD to plants like peyote.

This article discusses psychedelic substances, their history, and their different types. It also covers their therapeutic potential and possible risks.

History of Psychedelic Use

Use of hallucinogens goes back centuries in many cultures, and some are still used in religious ceremonies to experience spiritual or heightened states of awareness.

Hallucinogens were used in psychotherapy in the 1960s, but this was halted for mainly political reasons until quite recently. Psychological research has since revived the use of psychedelics in experimental psychological treatment.

Psychedelics are slowly reappearing in psychology and psychiatry as a viable way to treat anxiety, depression, post-traumatic stress disorder (PTSD), and more. However, regulated treatments are currently experimental and not accessible to many people.

While psychedelic therapy shows promise in the treatment of a number of mental health conditions, it is important to recognize that this research is still in the early stages. Psychedelics are not available for therapeutic purposes outside of limited research settings.

If you are looking to treat symptoms of a mental health condition, be sure to talk to a doctor about other treatment options that may help, such as therapy, prescribed medication, and meditation.

Types of Psychedelic Drugs

The following are some of the most commonly used psychedelic substances.

Acid (LSD)

Lysergic acid diethylamide (LSD) is a chemically synthesized hallucinogen, developed from ergot, a kind of mold that grows on the rye grain. Also known simply as acid, LSD was widely used in the 1960s until it was made illegal. Use of LSD has continued, despite being a controlled substance. 

Dimethyltryptamine (DMT)

Dimethyltryptamine (DMT) is a naturally occurring plant-based psychedelic found in the bark and nuts of certain trees from Central and South America. The effects of DMT are much shorter than those of other psychedelics, typically lasting only an hour.

Mescaline

Mescaline is a naturally occurring psychedelic substance found in certain species of cactus, the most well-known being the peyote cactus. The effects of mescaline are similar to those of LSD.

Although peyote is a Schedule I drug, and is therefore illegal, the listing of peyote as a controlled substance does not apply to the use of peyote in religious ceremonies of the Native American Church.

Any person who manufactures peyote for or distributes peyote to the Native American Church, however, is required to obtain registration annually and to comply with all other requirements of law.

Ololiuqui

Ololiuqui is a naturally occurring psychedelic that is found in the seeds of the morning glory flower, which grows in Central and South America. Like mescaline, ololiuqui has a long history of use in spiritual rituals among indigenous groups where the plant grows but unlike mescaline, it is not a controlled substance in the U.S.

Psilocybin

Psilocybin is a psychedelic substance found in certain fungi, sometimes referred to as magic mushrooms. There is a wide variety of hallucinogenic mushrooms, and their legal status is somewhat ambiguous, as they can be found growing wild in many parts of the world.

Mushrooms carry particularly high risks given the toxicity of some varieties, which can even be lethal.

Ecstasy

Ecstasy, or MDMA, is more difficult to categorize as a psychedelic because the hallucinogenic effects are less pronounced, and the mood-enhancing and stimulant effects are more noticeable than some other psychedelics. However, ecstasy can induce hallucinations and delusions. 

Ecstasy has also been associated with increased risks of health problems arising from overheating, dehydration, and water intoxication.

Effects of Psychedelic Drugs

The effects of psychedelic drugs vary depending on the person. Factors such as dosage, environment, and personality play a role in how psychedelics affect people.

Effects of psychedelic drugs may include:

  • Altered perception of time
  • Difficulty communicating clearly with others
  • Hallucinations such as feeling sensations, hearing sounds, and/or seeing images that aren't real
  • Heightened awareness or understanding
  • Increased energy
  • Lack of ability to think rationally
  • Mixed sensory experiences (e.g., seeing sounds)
  • Nausea
  • Spiritual experiences
  • Vivid sensory experiences

Short-term effects of LSD, peyote, and DMT may include an increase in heart rate. LSD and peyote may also cause an increase in body temperature. Additionally, LSD can cause dizziness, sleepiness, increased blood pressure, loss of appetite, dry mouth, sweating, numbness, weakness, tremors, and impulsive behavior.

Psilocybin can cause feelings of relaxation or introspection, but it can also produce nervousness, paranoia, and even feelings of panic.

Effects of peyote include uncoordinated movements, excessive sweating, and flushing. DMT can cause agitation and body/spatial distortions.

Ololiuqui's effects are similar to those of LSD, but the drug may also cause nausea, vomiting, headache, high blood pressure, and drowsiness.

Tolerance and Addiction

Psychedelics do not appear to be addictive. Addiction is defined as chronic use of a substance despite negative consequences. 

However, some hallucinogenic drugs may lead to tolerance and some people report experiencing withdrawal effects when they stop using such substances. 

LSD use can lead to tolerance, which means people require more of the substance in order to achieve the same effects. This can be risky due to the unpredictable effects that the drug may have. 

Cross-tolerance to other substances can also occur. Developing a tolerance to LSD means that people will experience a decreased reaction to some substances, including mescaline and psilocybin.

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area.

For more mental health resources, see our National Helpline Database.

8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Fuentes JJ, Fonseca F, Elices M, Farré M, Torrens M. Therapeutic use of LSD in psychiatry: A systematic review of randomized-controlled clinical trials. Front Psychiatry. 2020;10. doi:10.3389/fpsyt.2019.00943

  2. Tupper KW, Wood E, Yensen R, Johnson MW. Psychedelic medicine: A re-emerging therapeutic paradigmCMAJ. 2015;187(14):1054-1059. doi:10.1503/cmaj.141124

  3. Graziano S, Orsolini L, Concetta Rotolo M, Tittarelli R, Schifano F, Pichini S. Herbal highs: Review on psychoactive effects and neuropharmacology. Curr Neuropharmacol. 2017;15(5):750-761. doi:10.2174/1570159X14666161031144427

  4. National Institute on Drug Abuse. How do hallucinogens work?.

  5. Nichols DE. PsychedelicsPharmacol Rev. 2016;68(2):264-355. doi:10.1124/pr.115.011478

  6. American Psychiatric Association (APA). Diagnostic and Statistical Manual of Mental Disorders. 5th ed, text revision. Washington, D.C.; 2022.

  7. National Institute on Drug Abuse. Is MDMA addictive?

  8. National Institute on Drug Abuse. What are hallucinogens?

By Elizabeth Hartney, BSc, MSc, MA, PhD
Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.