Hallucinogens | Types, Effects, & Risks

The two main types of hallucinogens, classical hallucinogens and dissociative drugs, are not as addictive as other illegal drugs. However, they pose several health risks and impact your thoughts feelings, and sensory perceptions.

Hallucinogens (also called hallucinogenic drugs or psychedelic drugs) are psychoactive substances that impact your thoughts, feelings, and sensory perceptions. Some hallucinogens are synthetic (human-made), while others are made from plants or mushrooms.

In general, hallucinogens are not as addictive as other illegal drugs. However, they pose a variety of health risks.

There are two main types of hallucinogens: classic hallucinogens and dissociative drugs.

Classic Hallucinogens

According to the National Institute on Drug Abuse, classic hallucinogens impact neurotransmitters (brain chemicals) that help regulate mood and behavior.

They often cause you to hallucinate (see, hear, or feel things that aren’t there). The most common types of classic hallucinogens are:


DMT (also called N, N-dimethyltryptamine) is a substance found in certain Amazonian plants. Some of those plants are used to make a psychoactive tea called ayahuasca. DMT can also be created artificially in a lab, where it’s made into a smokable powder.


LSD (also called lysergic acid diethylamide) is a white or clear substance made from ergot, which is a fungus that grows on rye and other grains.

It comes in tablet, powder, or liquid form. The powder form can be inhaled or mixed with water and injected. The liquid form can be applied to blotter paper and then licked.

Peyote Cactus

The peyote cactus is a small cactus with a psychoactive ingredient called mescaline. It grows in the southwestern United States and northern Mexico. It can also be manufactured in a lab.


Psilocybin (also called magic mushrooms or shrooms) is a substance found in certain mushrooms grown in the United States, Mexico, and South America. The mushrooms are typically eaten or brewed in tea.

Dissociative Drugs

Like classic hallucinogens, dissociative drugs can cause hallucinations. They can also cause dissociation, which is a feeling of disconnection from your surroundings or body. The most common types of dissociative drugs are:


Dextromethorphan (DXM) is a human-made chemical that acts as a cough suppressant. It appears in certain over-the-counter cough and cold medications.


Ketamine is a human-made chemical that’s used as an anesthetic before surgery. It’s sold on the street in pill, powder, or liquid form.

Phencyclidine (PCP)

Phencyclidine (also called PCP or angel dust) is a human-made chemical that was used as a surgery anesthetic before being discontinued due to negative side effects. It continues to be sold illegally in tablet, powder, or liquid form.

Salvia Divinorum

Salvia divinorum is a plant grown in Mexico, Central America, and South America. Most people use it by drinking the plant’s juices or chewing their leaves.

Effects & Risks Of Classic Hallucinogens

The effects of classic hallucinogens usually start within 90 minutes and last up to 12 hours, depending on the drug. Their most common effects include:

  • hallucinations
  • heightened feelings and/or mood swings
  • relaxation
  • panic
  • paranoia (irrational distrust of others)
  • nausea
  • dry mouth
  • loss of appetite
  • increased heart rate, breathing rate, blood pressure, or body temperature
  • sweating
  • changes in sensory perception (such as seeing brighter colors or hearing louder sounds)
  • distortions in sense of time


The effects of hallucinogens can also lead to psychosis. Psychosis refers to a temporary loss of connection with reality. Common symptoms include:

  • hallucinations
  • delusions (irrational beliefs)
  • paranoia
  • extreme anxiety
  • trouble thinking and/or communicating

Bad Trips & Flashbacks

An experience on hallucinogens is often called a “trip.” Experiences that include unpleasant side effects like panic and psychosis are often called “bad trips.”

In rare cases, some people experience flashbacks to certain hallucinogenic effects (such as hallucinations) for months or even years.

This is called hallucinogen persisting perception disorder (HPPD). You face a higher risk of HPPD if you have a preexisting mental illness, such as bipolar disorder or schizophrenia.

Cravings & Withdrawal

In addition, while scientists have not yet determined whether hallucinogens are addictive, some of them may cause symptoms of substance use disorder, particularly cravings and withdrawal symptoms. Withdrawal symptoms are unpleasant symptoms (such as anxiety or sweating) you experience when you stop using a drug.

Effects & Risks Of Dissociative Drugs

The effects of dissociative drugs generally start within a few minutes and last up to several hours or, in rare cases, days. They affect a brain chemical called glutamate, which regulates your feelings, learning, and memory. The most common effects of dissociative drugs include:

  • numbness
  • hallucinations
  • disorientation and impaired coordination
  • increased heart rate, breathing rate, blood pressure, or body temperature

Long-Term Mental Health Issues

The drugs can also have long-term effects, such as:

  • anxiety
  • depression and suicidal thoughts
  • trouble speaking
  • memory problems

Also, as with classic hallucinogens, some dissociative drugs can cause cravings and withdrawal symptoms. In addition, regular use of phencyclidine can cause addiction, especially at high doses.

That means you will feel unable to stop using phencyclidine even if you want to. Like other diseases, phencyclidine addiction requires professional treatment.

To learn about treatment options for hallucinogen abuse or other types of drug use, please contact Northeast Addictions Treatment Center. Our substance abuse treatment programs offer mental health counseling, support groups, and many other forms of evidence-based care.

Written by
Northeast Addition Editorial Team

Published on

©2023 Northeast Addition Center | All Rights Reserved

This page does not provide medical advice.

Ready to make a change? Talk to a specialist now.