What Are Hallucinogens?
The Drug Enforcement Administration says many hallucinogenic drugs are illegal, as they have a high potential for abuse and aren’t considered safe. Drugs like PCP, for example, can cause seizures and death at high doses. These drugs are not safe for anyone to abuse.
Hallucinogens are substances that change the way you perceive reality. The National Institute on Drug Abuse splits these drugs into the following three classes:
- Psychedelic: These drugs cause visions and alter a person’s sense of self. Changes to the serotonin system cause these effects.
- Dissociative: These drugs make people feel disconnected from their body or environment. Changes in the brain’s processing of glutamate are responsible.
- Other: These drugs cause a mixture of psychedelic and dissociative symptoms and can work on a variety of brain functions.
Key Facts About Hallucinogens
- Hallucinogens work by disrupting the serotonin system, altering processing of glutamate, or suppressing core brain functions.
- Hallucinogens have been studied for their therapeutic value since the 1940s. Experts remain divided if they help or harm users.
- Most classic hallucinogens produce very unpleasant experiences at high doses, but the resulting issues rarely put your life at risk. However, some synthetic hallucinogens have caused both medical emergencies and fatalities.
- Researchers say psychedelic drugs like psilocybin and LSD typically don’t lead to addiction, as side effects can be unpleasant. But more research must be done to understand how addictive other versions might be.
History & Scheduling
Some types of hallucinogens have been used for hundreds of years. Others are relatively new, and researchers don’t know much about how they work. Many hallucinogens are Schedule I substances, meaning they have a high potential for abuse with no accepted medical use.
In 2021, 8% of young adults admitted to past-year hallucinogen use — an all-time high. In 2011, only 3% of teens said the same.
In 2019, experts estimated that more than 5.5 million American adults used hallucinogens.
Hallucinogens as Treatment
In some states like California, voters are debating hallucinogenic drugs. Laws moving through legislative offices could legalize some forms of hallucinogens. News coverage of these drugs and their supposed benefits could convince new users that these substances are both effective and safe.
The U.S. Food and Drug Administration (FDA) has approved ketamine to treat depression. The FDA also approved psilocybin research as a potential depression therapy.
Researchers aren’t sure if hallucinogens can help everyone with mental health issues. Much more research must be done to determine dosing, scheduling, and toxicity levels.
Commonly Abused Hallucinogens
The term hallucinogen is broad and refers to many different drugs. All of them cause perception changes, but they’re called different things and appeal to different people. These are a few examples:
D-lysergic acid diethylamide (commonly known as LSD) is made from a grain-based fungus. It’s typically sold in powder format, and granules are white and odorless. Users snort the powder, or dealers lace papers with powder that can be placed inside the cheeks for oral distribution.
LSD street names include acid, dots, and mellow yellow.
Some mushrooms grown in South America, Mexico, and the United States contain psilocybin, a natural hallucinogen. Users buy dried mushrooms that can be chewed, baked into foods like eggs, or brewed into tea.
Psilocybin street names include magic mushrooms and shrooms.
A small cactus grown in very warm climates contains peyote, but some chemists synthesize the drug in their laboratories. Cactus parts can be chewed, brewed into tea, or baked into food. Synthetic versions come in almost every formulation you can think of.
Peyote street names include cactus, buttons, and mesc.
DMT is a hallucinogenic and psychedelic drug. While it occurs naturally in plants and animals, chemists can synthesize the drug in labs and sell it to curious people.
DMT street names include the spirit molecule and the Rogan.
In the 1950s, chemists developed PCP to help prepare people for surgery, but the drug fell out of favor for its severe side effects. Typically, dealers sell the drug in a liquid or crystal format, but people can also buy tablets and capsules packed with PCP.
Street names include angel dust, ozone, and rocket fuel.
The salvia plant grows abundantly in Mexico and South America, but it’s also widely available in garden centers. Chewing fresh leaves or drinking the juice are common ways for people to abuse this drug.
Street names include Sally-D and Maria Pastora.
Ayahuasca is a plant-based drug sourced from South American fields. It’s traditionally brewed into a hot tea and included as part of ceremonial or shamanic events.
This drug doesn’t have common street names. People just use its formal name.
Both surgeons and veterinarians use ketamine to prepare patients for surgery. Often, people who abuse this drug buy it from people who stole it from legitimate medical offices.
Ketamine is often sold in a liquid, injectable format. But some dealers have pills and powder available.
Street names include special K, kit kat, and cat valium.
Side Effects: How Hallucinogens Affect the Body
Hallucinogenic drugs all work by changing electrical or chemical signals deep inside the brain. The damage you’ll face varies according to how much you take and how long the abuse lasted. The side effects of shrooms can be different than those associated with other drugs, so the type of hallucinogen you use matters too.
Hallucinogens cause a break with reality. People say and do things they might never do while sober. People can do strange-seeming things like run into traffic or hurt their families while under the influence.
Other short-term health effects of hallucinogen use may include the following:
- Cardiovascular problems, like high blood pressure or a fast pulse
Dissociative drugs like ketamine and PCP can also cause loss of coordination and numbness. 
Classic hallucinogens like LSD and psilocybin can cause changes that stick with you for years. Some people develop symptoms of psychosis, including hallucinations, that won’t ease due to the long-term effects of shrooms and other classic hallucinogens.
Others develop flashbacks of terrifying moments from their long-gone high. These episodes can be debilitating, and some people refuse to do things like drive or go to job interviews as they worry the problems will reappear. 
Dissociative hallucinogens can cause similar issues, such as memory loss and anxiety, that continue long after the drug use stops.
Experts say some hallucinogens can be addictive, and others can cause physical dependence.
Drugs like PCP can spark brain changes, making cells work best when the substance is present. People who try to quit feel sick, and they crave the drug they’ve left behind.
Other hallucinogenic drugs cause a psychological addiction, enticing people to keep taking the drug to avoid their current reality.
Mixing Hallucinogens & Other Drugs
Some people use hallucinogens indiscriminately in party-like situations. They take whatever drugs are handed to them, and sometimes, they mix hallucinogens. Others combine substances deliberately to make hallucinogen’s side effects easier to bear.
The risks aren’t easy to understand as researchers haven’t studied them extensively. But experts do know that people using hallucinogens mix them with the following substances often:
- Stimulants: The practice enhances a feeling of power, but it can place further strain on the heart.
- Benzodiazepines: People hope these drugs can reduce anxiety and nervousness, but the mixture can enhance distress and speed up the heart.
People buying hallucinogens may mix drugs inadvertently. It’s impossible to know if the substances people purchase contain the drugs the dealers claim they do.
Signs & Symptoms of Abuse: What to Look Out For
People who abuse hallucinogenic drugs display symptoms that can fall into three categories. Knowing what they are can help you understand when someone you love needs help.
Disheveled clothing, unwashed bodies, and poor grooming are all common in people with addictions. Hallucinogens can also cause cardiovascular issues, insomnia, and sweating. Some dissociative drugs cause loss of coordination.
People may feel happy and good when they’re taking drugs or know they’ll use soon. They can feel depressed or upset when they try to quit. Some people develop paranoia and psychosis, including flashbacks.
People skip work, drop out of classes, and lose friends to make more time for drug use. People sell treasured items or steal things to raise money for drugs.
People using hallucinogens see, hear, smell, and taste things others can’t. They may act erratically or violently while on drugs. People with addictions may behave like this almost all the time.
|Physical Symptoms||Mental Symptoms||Behavioral Symptoms|
|Poor grooming||Paranoia||Increased isolation and a need for privacy|
|Insomnia||Psychosis, including flashback episodes||Violent or erratic episodes while high|
|Loss of coordination||Happiness while intoxicated and depression while sober||Stealing to pay for drugs|
Withdrawal Symptoms & Detox
The hallucinogen class is large, and some types don’t cause withdrawal symptoms. But people who are dependent on dissociative hallucinogens (such as ketamine) can develop withdrawal when they quit the drug quickly.
Ketamine withdrawal symptoms can include the following:
- Emotional instability
Symptoms can appear within 24 hours of the last dose and persist for weeks. Treatment teams may offer supportive care, including medications, to address symptoms as they arise and provide relief. The safe environment of a detox program can ensure people don’t relapse to drugs.
Treatment for Hallucinogen Addiction
No FDA-approved hallucinogen addiction treatment drugs exist. But many people addicted to hallucinogens find relief through drug addiction treatment programs.
Counselors can use techniques like cognitive behavioral therapy to help you unpack the origins of your drug misuse, so you’ll understand why you started taking drugs to begin with. Your therapists can also help you come up with relapse prevention skills, so you can learn to avoid triggers and stay away from substance abuse for good.
If you’ve tried to quit using and can’t, start by talking to your doctor. With a solid addiction treatment team in place, you can create a plan for your future.
Frequently Asked Questions About Hallucinogens
We’ve compiled some of the most frequently asked questions about hallucinogen abuse.
Some of them are. Others may not cause a physical addiction and withdrawal syndrome, but people can become psychologically attached to them.
It depends. Some work on the serotonin system, others alter brain chemistry levels, and others work in a completely different way. The hallucinogen drug class is large.
Hallucinogens can be swallowed, consumed as tea, snorted, injected, inhaled, or absorbed via oral tissues.
The Drug Enforcement Administration says many hallucinogenic drugs are illegal, as they have a high potential for abuse and aren’t considered safe.
Most hallucinogenic drugs stay in your body (and detectable on most drug tests) for several days.
- Hallucinogens. Drug Enforcement Administration. Published April 2020. Accessed June 20, 2023.
- Psychedelic and dissociative drugs. National Institute on Drug Abuse. Published April 2023. Accessed June 20, 2023.
- Can psychedelic drugs heal? American Psychological Association. Published August 9, 2018. Accessed June 20, 2023.
- Marijuana and hallucinogen use among young adults reached all time-high in 2021. National Institute on Drug Abuse. Published August 22, 2022. Accessed June 20, 2023.
- New study estimates over 5.5 million U.S. adults use hallucinogens. Columbia Mailman School of Public Health. Published August 18, 2022. Accessed June 20, 2023.
- Garcia, M. Will psychedelics become legal in California? CalMatters. Published August 26, 2021. Accessed June 20, 2023.
- Chary, M. and Yi, D. and Manini, A. Candyflipping and other combinations: Identifying drug-drug combinations from an online forum. Sec. Neuropharmacology Volume 9 - 2018
- What are psychedelics? Alcohol and Drug Foundation. Published August 16, 2022. Accessed June 20, 2023.
- A Potential Case of Acute Ketamine Withdrawal: Clinical Implications for the Treatment of Refractory Depression. Roxas, N. Ahuja, C., Isom, J., Wilkinson, S.T., and Capurso, N. (2021). The American Journal of Psychiatry 178(7): 588-591.