Hallucinogens and Dissaciatives
What Are They?
Hallucinogens are a class of drugs that cause hallucinations—profound distortions in a person’s perceptions of reality. Hallucinogens can be found in some plants and mushrooms (or their extracts) or can be man-made, and they are commonly divided into two broad categories: classic hallucinogens (such as LSD) and dissociative drugs (such as PCP). When under the influence of either type of drug, people often report rapid, intense emotional swings and seeing images, hearing sounds, and feeling sensations that seem real but are not.
While the exact mechanisms by which hallucinogens and dissociative drugs cause their effects are not yet clearly understood, research suggests that they work at least partially by temporarily disrupting communication between neurotransmitter systems throughout the brain and spinal cord that regulate mood, sensory perception, sleep, hunger, body temperature, sexual behavior, and muscle control.
Classic hallucinogens are thought to produce their perception-altering effects by acting on neural circuits in the brain that use the neurotransmitter serotonin (Passie, 2008; Nichols, 2004; Schindler, 2012; Lee, 2012). Specifically, some of their most prominent effects occur in the prefrontal cortex—an area involved in mood, cognition, and perception—as well as other regions important in regulating arousal and physiological responses to stress and panic.
Alternative Names
LSD (d-lysergic acid diethylamide) is one of the most potent mood- and perception-altering hallucinogenic drugs. It is a clear or white, odorless, water-soluble material synthesized from lysergic acid, a compound derived from a rye fungus. LSD is initially produced in crystalline form, which can then be used to produce tablets known as “microdots” or thin squares of gelatin called “window panes.” It can also be diluted with water or alcohol and sold in liquid form. The most common form, however, is LSD-soaked paper punched into small individual squares.
Psilocybin(4-phosphoryloxy-N,N-dimethyltryptamine) is extracted from certain types of mushrooms found in tropical and subtropical regions of South America, Mexico, and the United States. In the past, psilocybin was ingested during religious ceremonies by indigenous cultures from Mexico and Central America. Psilocybin can either be dried or fresh and eaten raw, mixed with food, or brewed into a tea, and produces similar effects to LSD.
Peyote (Mescaline) is a small, spineless cactus with mescaline as its main ingredient. It has been used by natives in northern Mexico and the southwestern United States as a part of religious ceremonies. The top, or “crown,” of the peyote cactus has disc-shaped buttons that are cut out, dried, and usually chewed or soaked in water to produce an intoxicating liquid. Because the extract is so bitter, some users prepare a tea by boiling the plant for several hours. Mescaline can also be produced through chemical synthesis.
DMT (Dimethyltryptamine) is a powerful hallucinogenic chemical found naturally occurring in some Amazonian plant species (see “Ayahuasca”) and also synthesized in the laboratory. Synthetic DMT usually takes the form of a white crystalline powder and is typically vaporized or smoked in a pipe.
Ayahuasca is a hallucinogenic brew made from one of several Amazonian plants containing DMT (the primary psychoactive ingredient) along with a vine containing a natural alkaloid that prevents the normal breakdown of DMT in the digestive tract. Ayahuasca tea has traditionally been used for healing and religious purposes in indigenous South American cultures, mainly in the Amazon region.
Dissociative Drugs
PCP (Phencyclidine) was originally developed in the 1950s as a general anesthetic for surgery. While it can be found in a variety of forms, including tablets or capsules, it is usually sold as a liquid or powder. PCP can be snorted, smoked, injected, or swallowed. It is sometimes smoked after being sprinkled on marijuana, tobacco, or parsley.
Ketamine is a dissociative currently used as an anesthetic for humans as well as animals. Much of the ketamine sold on the street has been diverted from veterinary offices. Although it is manufactured as an injectable liquid, ketamine is generally evaporated to form a powder that is snorted or compressed into pills for illicit use. Because ketamine is odorless and tasteless and has amnesia-inducing properties, it is sometimes added to drinks to facilitate sexual assault.
DXM (Dextromethorphan) is a cough suppressant and expectorant ingredient in some over-the-counter (OTC) cold and cough medications that are often abused by adolescents and young adults. The most common sources of abused DXM are “extra-strength” cough syrup, which typically contains around 15 milligrams of DXM per teaspoon, and pills and gel capsules, which typically contain 15 milligrams of DXM per pill. OTC medications that contain DXM often also contain antihistamines and decongestants.
Salvia divinorum is a psychoactive plant common to southern Mexico and Central and South America. Salvia is typically ingested by chewing fresh leaves or by drinking their extracted juices. The dried leaves of salvia can also be smoked or vaporized and inhaled.
Legality
Most are not sold over the counter or are prescribed. DXM can be purchased over the counter in cough syrups. Salvia divinorum is a decorate plant that can be purchased in garden center. Ketamine is a scheduled drug that is used in medical settings.
Common Forms
See above.
Common Ways Taken
These are taken orally, smoked, or injected.
Short Term Effects of Hallucinogens
Ingesting hallucinogenic drugs can cause users to see images, hear sounds, and feel sensations that seem real but do not exist. Their effects typically begin within 20 to 90 minutes of ingestion and can last as long as 12 hours. Experiences are often unpredictable and may vary with the amount ingested and the user’s personality, mood, expectations, and surroundings. The effects of hallucinogens like LSD can be described as drug-induced psychosis—distortion or disorganization of a person’s capacity to recognize reality, think rationally, or communicate with others. Users refer to LSD and other hallucinogenic experiences as “trips” and to acute adverse or unpleasant experiences as “bad trips.” On some trips, users experience sensations that are enjoyable and mentally stimulating and that produce a sense of heightened understanding. Bad trips, however, include terrifying thoughts and nightmarish feelings of anxiety and despair that include fears of losing control, insanity, or death.
Like LSD and psilocybin, DMT produces its effects through action at serotonin (5-HT) receptors in the brain (Strassman, 1996). Some research has suggested that DMT occurs naturally in the human brain in small quantities, leading to the hypothesis that release of endogenous DMT may be involved in reports of alien abductions, spontaneous mystical experiences, and near-death experiences, but this remains controversial (Barker, 2012).
Specific short-term effects of LSD, psilocybin, peyote, DMT, and ayahuasca include:
LSD
- Increased blood pressure, heart rate, and body temperature
- Dizziness and sleeplessness
- Loss of appetite, dry mouth,and sweating
- Numbness, weakness, and tremors
- Impulsiveness and rapid emotional shifts that can range from fear to euphoria, with transitions so rapid that the user may seem to experience several emotions simultaneously
Psilocybin
- Feelings of relaxation (similar to effects of low doses of marijuana)
- Nervousness, paranoia, and panic reactions
- Introspective/spiritual experiences
- Misidentification of poisonous mushrooms resembling psilocybin could lead to unintentional, potentially fatal poisoning
Peyote
- Increased body temperature and heart rate
- Uncoordinated movements (ataxia)
- Profound sweating
- Flushing
DMT
- Increased heart rate
- Agitation
- Hallucinations frequently involving radically altered environments as well as body and spatial distortions
Ayahuasca
- Increased blood pressure
- Severe vomiting (induced by the tea)
- Profoundly altered state of awareness and perceptions of otherworldly imagery
Short-Term General Effects of Hallucinogens
Sensory Effects
- Hallucinations, including seeing, hearing, touching, or smelling things in a distorted way or perceiving things that do not exist
- Intensified feelings and sensory experiences (brighter colors, sharper sounds)
- Mixed senses (“seeing” sounds or “hearing” colors)
- Changes in sense or perception of time (time goes by slowly)
Physical Effects
- Increased energy and heart rate
- Nausea
Short Term Effects of Dissociatives
Dissociative drugs can produce visual and auditory distortions and a sense of floating and dissociation (feeling detached from reality) in users. Use of dissociative drugs can also cause anxiety, memory loss, and impaired motor function, including body tremors and numbness. These effects, which depend on the amount of the drug taken, are also unpredictable—typically beginning within minutes of ingestion and lasting for several hours, although some users report feeling the drug’s effects for days. See text box for general effects of dissociative drugs.
Low Doses
- Numbness
- Disorientation, confusion, and loss of coordination
- Dizziness, nausea, vomiting
- Changes in sensory perceptions (such as sight, sound, shapes, time, and body image)
- Hallucinations
- Feelings of detachment from self and environment
- Increase in blood pressure, heart rate, respiration, and body temperature
High Doses
- Hallucinations
- Memory loss
- Physical distress, including dangerous changes in blood pressure, heart rate, respiration, and body temperature
- Marked psychological distress, including feelings of extreme panic, fear, anxiety, paranoia, invulnerability, exaggerated strength, and aggression
- Use with high doses of alcohol or other central nervous system depressants can lead to respiratory distress or arrest, resulting in death
In addition to these general effects, different dissociative drugs can produce a variety of distinct and dangerous effects. For example, at moderate to high doses, PCP can cause a user to have seizures or severe muscle contractions, become aggressive or violent, or even experience psychotic symptoms similar to schizophrenia. At moderate to high doses, ketamine can cause sedation, immobility, and amnesia. At high doses, ketamine users also report experiencing terrifying feelings of almost complete sensory detachment likened to a near-death experience (called a “K-hole,” similar to a bad LSD trip). Salvia users report intense but short-lived effects—up to 30 minutes—including emotional mood swings ranging from sadness to uncontrolled laughter.
DXM, which is safe and effective as a cough suppressant and expectorant when used at recommended doses (typically 15 to 30 milligrams), can lead to serious side effects when abused. For example, use of DXM at doses from 200 to 1,500 milligrams can produce dissociative effects similar to PCP and ketamine and increase the risk of serious central nervous system and cardiovascular effects such as respiratory distress, seizures, and increased heart rate from the antihistamines found in cough medicines.
Long Term Effects of Hallucinagens
Persistent psychosis
- Visual disturbances
- Disorganized thinking
- Paranoia
- Mood disturbances
Hallucinogen Persisting Perception Disorder (HPPD)
- Hallucinations
- Other visual disturbances (such as seeing halos or trails attached to moving objects)
- Symptoms sometimes mistaken for neurological disorders (such as stroke or brain tumor)
Long Term Effects of Dissaciatives
While the long-term use of most dissociative drugs has not been investigated systematically, research shows that repeated use of PCP can lead to tolerance and the development of a substance use disorder that includes a withdrawal syndrome (including craving for the drug, headaches, and sweating) when drug use is stopped. Other effects of long-term PCP use include persistent speech difficulties, memory loss, depression, suicidal thoughts, anxiety, and social withdrawal that may persist for a year or more after chronic use stops.
When Combined With Alcohol
Hallucinogens are drugs that cause distortions in a person’s reality. When mixed with alcohol, the interaction can lead to potentially dangerous side effects including drug or alcohol hallucinations, toxicity or overdose, and psychosis.
Alcohol and hallucinogens are mind-altering substances. Both affect the brain’s structure, changing how neurotransmitters communicate. Specifically, these substances interfere with glutamate, serotonin, and dopamine.
Alcohol and hallucinogens can send mixed signals to the brain, confusing the messages sent throughout the body. When mixing alcohol and hallucinogens, you have the potential of experiencing the adverse effects of both substances at the same time.
Withdrawal Symptoms
PCP is a hallucinogen that can be addictive. People who stop repeated use of PCP experience drug cravings, headaches, and sweating as common withdrawal symptoms.
Additional Information
Ketamine was approved many years ago as an anesthetic for painful medical procedures. In March 2019, the medicine esketamine (called “Spravato” by the manufacturer) was approved by the Food and Drug Administration as a treatment for severe depression in patients that do not respond to other treatments. Esketamine is closely related to the drug ketamine which is used illicitly and so there are concerns about the potential for misuse of this newly approved medication. In response, esketamine will be limited to administration in medical facilities.
Unlike a prescription that can be taken home and might be diverted into recreational use, esketamine will be administered in a medical office as a nasal spray. Patients must wait at least 2 hours under medical supervision to ensure proper management of potential side effects. It is a rapid acting medication, so improvements may be seen immediately or within the first few weeks of treatment (unlike most other antidepressants which can take weeks to begin to show an effect). Traditional antidepressants target the neurotransmitters serotonin, norepinephrine or dopamine. Esketamine affects the receptor for a different brain chemical called glutamate and so it represents a new approach to treating depression.
There is also some evidence that psilocybin may be effective in treating depression and anxiety.1 The FDA has granted “Breakthrough Therapy” designation for two formulations of psilocybin being studied for safety and efficacy as a medical treatment for depression. It’s important to note that during such studies, psilocybin is always taken under medical supervision.
Sources: NIH, CDC, National Institute on Drug Abuse. (Collected 2023)