Chapter 7: Hallucinogens

By the end of this chapter, you should be able to:

  • Examine the dominant beliefs and attitudes in our society with regard to chemical use. (LO1)
  • Define the characteristics of the major classes of drugs. (LO2)
  • Identify and summarize the addiction process and the characteristics thereof. (LO3)


"Hallucinogenic Plants A Golden Guide" by Howard G Charing is licensed under CC BY-NC 2.0.
Hallucinogenic Plants A Golden Guide” by Howard G Charing is licensed under CC BY-NC 2.0.

Hallucinogens are a tricky batch of drugs that can act like stimulants or act as depressants. This group of drugs may produce a sensory effect leading to additional alternations in perception, cognition, and mood (APA, 2022). These drugs can also be called psychedelic drugs and include: LSD, psilocybin mushrooms, peyote, MDMA, ketamine, PCP, DMT, and marijuana. These drugs are generally sorted into two categories: classic hallucinogens (like LSD) and dissociative drugs (like PCP) (NIDA, 2015). While there is a negative stigma associated with this group of drugs, there is burgeoning research that suggests there are medical and therapeutic uses for these drugs. Generally, there is a slim chance of: toxicity, addiction, dependence, and neurological affects during or after use (Lowe, 2022; Matzopoulos et al., 2022).

LSD (Lysergic acid diethylamide)

File:Claviceps purpurea 47424140.jpg” by Kasper Malmberg is licensed under CC BY 4.0.

LSD is very strong drug in this category that mimics neurotransmitters exerting its psychoactive effects on the user. It is unique because it interacts with both serotonin and dopamine receptors (Lowe, 2022).  LSD has many aliases including but not limited to: acid, sugar cubs, trips, tabs, or windowpanes. Derived from a fungus (show at left), it is nearly undetectable and water soluble.  The most common way to take this drug, besides orally, is for LSD-soaked paper to be cut into small, but potent, circles (NIDA, 2015).

Early in its history, LSD was used to treat alcoholism and neurosis. But more recent studies have seen improvements in users who have the following diseases or situations: Alzheimer’s disease, schizophrenia, multiple sclerosis, criminal behavior, autism, frigidity, and many others (Lowe, 2022; Oehen & Gaser, 2022).

Short-term sides effects of LSD are (NIDA, 2015):

  • Increased blood pressure and temperature
  • Dizziness and fatigue
  • Appetite suppression
  • Feelings of numbness, weakness, and tremors
  • Increase impulsivity and moodiness

Psilocybin Mushroom

"Psilocybe Mexicana" by Quasimondo is licensed under CC BY-NC 2.0.
Psilocybe Mexicana” by Quasimondo is licensed under CC BY-NC 2.0.

The mushrooms (shown at right) has play an integral role in cultural traditions throughout Central and South America for centuries (Matzopoulos et al., 2022; Rootman et al., 2022). The effects users experienced were considered magical up to deep religious and spiritual experiences (Lowe, 2022; NIDA, 2015; Arce & Winkelman et al., 2021). Because of its vital cultural role, it is one of the most studied psychedelic drugs. Currently, there are promising therapeutic uses for psilocybin mushrooms, like treating painful conditions, heart conditions, or mood and anxiety disorders, especially in the era of the COVID-19 pandemic (Lowe, 2022; Matzopoulos et al., 2022; Nkadimeng et al., 2020).  The mushrooms can be consumed, orally, in a variety of ways ranging from raw to brewed with tea (NIDA, 2015); studies indicate that small doses are effective in treating symptoms without impairing regular functioning of the individual (Rootman et. al, 2022).

Short-term side effects of psilocybin mushrooms are (NIDA, 2015):

  • Sense of ease or relaxation
  • Anxiety
  • Introspection
  • Poisoning due to misidentification of mushrooms


"Xochipilli, Aztec 'Prince of Flowers' - Hallucinogenic Plants A Golden Guide" by Howard G Charing is licensed under CC BY-NC 2.0.
Xochipilli, Aztec ‘Prince of Flowers’ – Hallucinogenic Plants A Golden Guide” by Howard G Charing is licensed under CC BY-NC 2.0.

Peyote is a small cactus with its main ingredient being mescaline. It has been used in Central and North America during cultural and religious experiences. The intoxicating liquid, produced when processing the cactus, that it is usually consumed via tea to tamp down the excessively bitter flavor (NIDA, 2015; APA, 2022; Hinojosa, 2018). The future of peyote is uncertain as it is not being used in a sustainable way and therefore can not regrow as quickly as it is consumed (APA, 2022; Ermakova et al., 2020). Learn more about peyote harvest and some of the practices from this article: Peyote Veneration in Challenging Times: Issues of Land and Access in South Texas (2018) and watch the video below called Drinking Psychedelic Peyote Juice in Mexico (2021).

Short-term side effects of peyote are (NIDA, 2015):

  • Increased heart rate and temperature
  • Ataxia
  • Significant sweating

MDMA (Methylenedioxymethamphetamine)

This drug has an amphetamine-style experience with added hallucinations. It is typically sold as ecstasy. Individuals will experience the high very quickly and for a long time, even up to days (APA, 2022). Users of this drug may feel euphoric arousal with spiritual experiences. Research suggests that there are some long-term side effects like addiction, memory dysfunction, lack of control, and when used in high doses, it can be deadly (APA, 2022; Pantoni et al., 2022). And, other research has provided evidence that it can be beneficial in low-doses for safely treating intense disorders like PTSD (Mitchell et al., 2021; Arluk et al., 2022) and other anxiety-related experiences and disorders (Makunts et al., 2022; Oehen & Gaser, 2022)

Some side effects that can be experienced are (Oehen & Gaser, 2022)

  • Pain
  • Cramps
  • Dissociative symptoms
  • Sensory hallucinations


"ketamine" by juliankopald is marked with Public Domain Mark 1.0.
ketamine” by juliankopald is marked with Public Domain Mark 1.0.

Ketamine, a cousin to PCP, often results in the user being disoriented and hallucinating. Typically, this drug is ingested in pill or powder form (APA, 2022). At one time, ketamine was used in veterinarian offices (NIDA, 2015), but eventually came to treat a variety of painful conditions and addiction (Carboni, 2021; Marcus & Bruchas, 2021; Pribish, 2020), but more recently, it has been used to treat unique cases of bipolar-depression, where other treatments have proven ineffective (APA, 2022; Rawat et al., 2022; Yavi et al., 2022; Pribish, 2020). Because of its lack of odor and color, it has been used to spike drinks in order to commit sexual assault (NIDA, 2015). Ketamine is poorly understood or lacks the research to support potential benefits (Carboni, 2021; Marcus & Bruchas, 2021).

Side effects can include (Carboni, 2021):

  • Hallucinations
  • Nightmares or intense dreams
  • Delusions
  • Anesthesia (Pribish, 2020)


PCP was originally developed for surgical uses, but later it was realized that it produces hallucinogenic responses (APA, 2022) and is now sought out for recreational uses (Ryu et al., 2020). This drug can consumed in a number of ways, though when it is smoked it is usually combined with marijuana or tobacco (NIDA, 2015).

Symptoms of use, can include (APA, 2022):

  • Schizophrenia (both positive and negative symptoms)
  • Agitation
  • Delirium
  • Disorientation
  • Hallucinations

DMT and Ayahuasca

"Preparing Ayahuasca - Hallucinogenic Plants A Golden-Guide 102a" by Howard G Charing is licensed under CC BY-NC 2.0.
Preparing Ayahuasca – Hallucinogenic Plants A Golden-Guide 102a” by Howard G Charing is licensed under CC BY-NC 2.0.

DMT is a powerful psychoactive ingredient found in a plant species native to the Amazon. Synthetic versions of this drug are usually a white powder that is smoked. Ayahuasca is made from similar Amazonian plants as well, but is usually consumed in the form of tea in South America (NIDA, 2015; APA, 2022). These drugs are characterized by short periods of hallucinations (Timmermann et al., 2018; Alamia, 2020) and while it is generally safe to use, it cannot be easily broken down in the body and may negatively react with other drugs (Lowe, 2022). Ayahuasca is typically reserved for spiritual and cultural ceremonies but can also act as an aphrodisiac and in the diagnosis of other disorders (Lowe, 2022; APA, 2022). It is a trending component of South American tourism that began in the Amazon, but is spreading to other South American countries as well and beyond into North America and Europe (Lowe, 2022).

Side effects can include (APA, 2022):

  • Nausea
  • Vomiting
  • Tinnitus
  • Euphoria


"Cannabis Sativa - Hallucinogenic Plants A Golden Guide" by Howard G Charing is licensed under CC BY-NC 2.0.
Cannabis Sativa – Hallucinogenic Plants A Golden Guide” by Howard G Charing is licensed under CC BY-NC 2.0.

Also known as cannabis, these species of plants make up a very popular recreational drug. In fact, globally is it the most popular controlled substance (Graves et al., 2020; Latif & Garg, 2020) The psychoactive component known as THC, is contained in the flowers of the plant (APA, 2022). This drug is typically smoked and the user feels the high for roughly three hours. Learn more about cannabis, how it effects the brain, medicine, communities, and businesses by watching the playlist below.

Side effects can include (APA, 2022):

  • Euphoria
  • Hallucinations
  • Lack of memory or focus
  • Food cravings
  • Anxiety
  • Tolerance
  • Withdrawal

Research also suggests that there could be severe effects on the cardiovascular system by using this drug, check out this study for more information: The Impact of Marijuana on the Cardiovascular System: A Review of the Most Common Cardiovascular Events Associated with Marijuana Use (Latif & Garg, 2020).




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Psychology of Addiction by Andrea Bearman and Adelle Schwan is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

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