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The term “hallucinogen” encompasses a wide variety of substances, including natural compounds like psilocybin found in magic mushrooms and synthetic creations like lysergic acid diethylamide (LSD).


In medical settings, some hallucinogens have shown promise for treating conditions like depression, post-traumatic stress disorder (PTSD), and certain types of addiction. However, due to their potential for abuse and legal restrictions, the therapeutic use of hallucinogens remains a subject of ongoing debate and research.

Common risks

Hallucinogens, while intriguing and potentially therapeutic, carry a host of risks. Physically, they can lead to overdose, heart issues, and impaired motor skills. Psychologically, they can cause depersonalisation, anxiety, and long-term perceptual disorders. Behaviourally, they can result in poor decision-making and even psychological dependency. Socially, they can strain relationships and impact job performance. Legally, possession or distribution is often a criminal offence, leading to fines or imprisonment. Mixing hallucinogens with other substances can further elevate these risks. Understanding these multifaceted dangers is crucial for anyone considering the use of these potent substances.

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Hallucinogens Explained

The term “hallucinogen” encompasses a wide variety of substances, including natural compounds like psilocybin found in magic mushrooms and synthetic creations like lysergic acid diethylamide (LSD). The effects of hallucinogens can vary greatly, ranging from visual and auditory hallucinations to deeply introspective or spiritual experiences. Given their powerful psychoactive effects, they have been the subject of extensive study, both clinically and academically.

In medical settings, some hallucinogens have shown promise for treating conditions like depression, post-traumatic stress disorder (PTSD), and certain types of addiction. However, due to their potential for abuse and legal restrictions, the therapeutic use of hallucinogens remains a subject of ongoing debate and research.

Legally, hallucinogens are controlled substances in many countries, including the United Kingdom, where they are generally classified as Class A drugs under the Misuse of Drugs Act 1971. This classification means that they are considered to have a high potential for abuse and no accepted medical use, which has implications for possession, distribution, and research.

Understanding the complex effects and implications of hallucinogen use requires a multidisciplinary approach that includes neuroscience, psychology, sociology, law, and public health. This introduction serves as a foundation for delving deeper into the fascinating and controversial world of hallucinogens.

Definition and Classification

Hallucinogens are a class of psychoactive substances that primarily alter perception, thoughts, and feelings, leading to hallucinations or experiences that deviate from reality. These drugs can be derived from plants and fungi or be synthetically manufactured. The effects of hallucinogens can vary widely, depending on factors like dosage, environment, and the user’s mental state.


Hallucinogens can be classified into several categories based on their chemical structure and pharmacological effects:

  • Classic Psychedelics: This category includes substances like lysergic acid diethylamide (LSD), psilocybin (found in magic mushrooms), and mescaline (found in peyote and San Pedro cacti). These drugs primarily interact with serotonin receptors in the brain.
  • Dissociatives: Drugs like ketamine, phencyclidine (PCP), and dextromethorphan (DXM) fall under this category. They often act as NMDA receptor antagonists and create feelings of detachment from reality and self.
  • Deliriants: This category includes substances like atropine, scopolamine, and antihistamines in high doses. These drugs are anticholinergic and often lead to confusion, disorientation, and true hallucinations.
  • Research Chemicals: These are synthetic compounds designed to mimic the effects of traditional hallucinogens, such as 25I-NBOMe, which is similar to LSD, or synthetic cannabinoids which mimic the effects of THC.
  • Empathogens or Entactogens: Though not always classified as hallucinogens, drugs like MDMA (Ecstasy) have psychoactive properties that induce alterations in perception and mood, and are sometimes included in broader definitions of hallucinogens.
  • Plant-Based Hallucinogens: Natural substances like Salvia divinorum or Ayahuasca also fall into the hallucinogen category due to their psychoactive effects, although their chemical structures and mechanisms of action may differ from other hallucinogens.

Common Examples

LSD (Lysergic Acid Diethylamide): A synthetic chemical.

Psilocybin: Found in certain types of mushrooms.

DMT (Dimethyltryptamine): A naturally occurring psychedelic.

Mescaline: Found in the peyote cactus.

PCP (Phencyclidine): Originally developed as an anaesthetic.

Effects of Hallucinogens

Physical Effects

The physical effects of hallucinogens can vary widely depending on the substance, the dose, and the individual’s physiology. However, some common physical effects associated with the use of hallucinogens include:

  • Increased Heart Rate: Many hallucinogens can cause a significant increase in heart rate.
  • Elevated Blood Pressure: Users may experience a rise in blood pressure shortly after ingesting the substance.

Sensory Effects

  • Pupil Dilation: This is common among users of classic psychedelics like LSD and psilocybin.
  • Heightened Sensory Perception: Users often report enhanced senses, such as increased vividness of colours and auditory sensations.

Motor Skills and Coordination

  • Impaired Motor Skills: Hallucinogens like PCP can interfere with motor functions and coordination, potentially leading to accidents.

Other Physical Symptoms

  • Nausea: Substances like psilocybin mushrooms and peyote are often associated with gastrointestinal discomfort or nausea.
  • Tremors: Some users may experience muscle tremors or shakes.
  • Temperature Regulation: Users might also experience fluctuations in body temperature, including sweating or chills.

Long-term Physical Effects

  • Tolerance: Repeated use of some hallucinogens can lead to increased tolerance, requiring higher doses to achieve the same effect.
  • Physical Dependence: While most hallucinogens are not considered to be physically addictive, substances like ketamine can result in physical dependence with long-term use.

Understanding the physical effects of hallucinogens is essential for users, healthcare providers, and policymakers to make informed decisions about these substances. The physical effects often interact with the psychological effects, sometimes in unpredictable ways, which underscores the need for a cautious and informed approach to using these substances.

Psychological Effects

The psychological effects of hallucinogens can be both intriguing and complex, affecting various aspects of cognition, emotion, and perception. Below is a comprehensive overview of these effects:

Altered Perception of Reality

  • Visual Hallucinations: Often the most pronounced and well-known effect, where users see objects, patterns, or realities that aren’t present.
  • Auditory Hallucinations: Some users may hear sounds or voices that are not there.

Emotional Effects

  • Enhanced Emotional Sensitivity: Users often report heightened emotional states, both positive and negative.
  • Mood Swings: Rapid emotional transitions can occur, swinging from euphoria to anxiety within a short time frame.

Cognitive Effects

  • Altered Thought Process: Hallucinogens can change how people think, often causing them to make associations between ideas they might not usually connect to.
  • Impaired Judgment and Distorted Sense of Time: Decision-making abilities can be compromised, and the passage of time may feel accelerated or slowed down.

Sense of Self and Environment

  • Dissociation: Certain hallucinogens like ketamine and PCP can cause users to feel detached from their environment or themselves.
  • Spiritual or Mystical Experiences: Some users report a profound connection to a higher power or the universe, often described as mystical experiences.

Other Psychological Symptoms

  • Anxiety and Paranoia: Particularly with higher doses, hallucinogens can cause significant anxiety or paranoia.
  • Synaesthesia: A blending of the senses where, for example, sounds may be ‘seen’ or colours ‘heard’.

Long-term Psychological Effects

  • Flashbacks: Some users of hallucinogens like LSD report experiencing flashbacks or brief re-experiences of their trips days or even years after the fact.
  • HPPD (Hallucinogen Persisting Perception Disorder): A rare condition where visual distortions or hallucinations continue long after the drug has been metabolised.
  • It’s crucial to note that while some people find these experiences enlightening or therapeutic, they can be distressing or even traumatising for others. The psychological effects of hallucinogens can also vary depending on the context in which they are taken and the mental state of the user. Therefore, understanding these psychological effects is essential for any risk assessment or therapeutic application of these substances.

Types of Hallucinogens

Illicit Hallucinogenic Drugs

LSD (Lysergic acid diethylamide)

  • Street Names: Acid, Blotter, Dots, Tabs
  • Methods of Use: Swallowed or held under the tongue, often on blotter paper
  • Short-term Effects: Visual hallucinations, altered states of perception, elevated mood, distorted sense of time
  • Long-term Effects: Flashbacks, potential development of hallucinogen persisting perception disorder (HPPD)

Psilocybin (Magic Mushrooms)

  • Street Names: Shrooms, Magic Mushrooms
  • Methods of Use: Eaten fresh or dried, brewed in tea
  • Short-term Effects: Emotional sensitivity, hallucinations, altered perception of time and reality
  • Long-term Effects: Psychological dependency, increased risk of psychological disorders in predisposed individuals

DMT (Dimethyltryptamine)

  • Street Names: Dimitri, Businessman’s Trip, Businessman’s Special
  • Methods of Use: Smoked, sometimes injected or snorted
  • Short-term Effects: Intense visual hallucinations, emotional euphoria
  • Long-term Effects: Unknown due to limited research, potential for psychological dependency

Mescaline (Peyote)

  • Street Names: Buttons, Cactus, Mesc, Peyoto
  • Methods of Use: Chewed, swallowed or smoked
  • Short-term Effects: Altered state of consciousness, visual hallucinations
  • Long-term Effects: Flashbacks, potentially hallucinogen persisting perception disorder (HPPD)

Prescription Hallucinogens

  • Ketamine
  • Brand Names: Ketalar, Ketaset
  • Street Names: Special K, K, Kit Kat
  • Methods of Use: Injected, snorted, swallowed
  • Short-term Effects: Disorientation, loss of coordination, hallucinations
  • Long-term Effects: Bladder issues, cognitive decline, dependency

Phencyclidine (PCP)

  • Brand Names: Sernyl
  • Street Names: Angel Dust, Hog, Love Boat
  • Methods of Use: Smoked, injected, swallowed
  • Short-term Effects: Euphoria, hallucinations, distorted sense of time
  • Long-term Effects: Memory loss, depression, potential for addiction

Methods of Administration

The methods through which hallucinogens can be administered vary significantly and each has unique implications for the user.

Oral Consumption

Oral intake is a primary method for many hallucinogens like LSD, psilocybin mushrooms, and mescaline. The substance is often swallowed as a tablet, in a gelatine form, or consumed through food. This method is absorbed through the gastrointestinal tract, and the effects can take longer to set in but usually last longer. The liver metabolises the drug during the digestive process, altering its potency and duration.

Smoking or Vaporizing

Smoking is common for substances like DMT and Salvia divinorum. The hallucinogen is typically inhaled into the lungs, where it’s quickly absorbed into the bloodstream. This method provides an almost immediate onset of effects but can have risks associated with lung health.

Snorting (Intranasal Administration)

Snorting is less common but still a viable method for some hallucinogens, like certain forms of DMT. The powdered substance is inhaled through the nose and absorbed quickly through the mucous membranes. However, this can lead to damage to the nasal passages over time.


Injecting hallucinogens like DMT or synthetic derivatives is less common but extremely risky. It can occur intramuscularly or intravenously, leading to an almost instantaneous onset of effects. This method carries a high risk of infection, overdose, and other severe health complications.

Topical Application

Some hallucinogens, like certain forms of Ayahuasca and Iboga, are applied topically through the skin. Though this is less common, the effects are generally milder and take longer to manifest.

Sublingual Administration

Substances like LSD can also be administered sublingually by placing them under the tongue. This method allows for quicker absorption through the mucous membranes in the mouth, leading to a faster onset of effects.

Other Methods

Other less common methods include rectal administration, known as “plugging,” and transdermal patches. These methods are usually specific to certain types of hallucinogens and are less frequently employed due to their unconventional nature and the associated risks.

Understanding these methods of administration is crucial for both healthcare professionals and users to ensure the safe and effective use of hallucinogenic substances. Each method has its own set of associated risks and benefits, as well as implications for the onset and duration of effects.

The Dangers of Hallucinogen Abuse

Understanding the dangers associated with hallucinogen abuse is crucial for both healthcare providers and the public. The consequences are wide-ranging, affecting physical health, psychological well-being, social relationships, and even legal status. Below is a detailed explanation of these risks.

Physical Dangers

  • Overdose: Taking too much of a hallucinogen can be life-threatening. The risk of overdose is particularly high because the difference between a safe dose and a dangerous one can be very small. Overdosing can lead to severe health problems like difficulty breathing, seizures, and even death in extreme cases.
  • Impaired Motor Skills: Hallucinogens mess with your coordination. This means you’re more likely to have accidents or injuries while you’re under the influence. Simple tasks like walking can become dangerous, and operating heavy machinery or driving is out of the question.

Psychological Risks

  • Depersonalisation and Derealisation: High doses can make you lose touch with what’s real. You might feel like you’re watching yourself from outside your body or that the world around you isn’t real. These symptoms can lead to dangerous behaviours, including self-harm or accidents.
  • Severe Anxiety and Paranoia: Hallucinogens can make you feel extremely anxious or paranoid. If you already have anxiety issues, the drugs can make them much worse. In some cases, people have had panic attacks or felt extremely paranoid about things that wouldn’t usually bother them.

Behavioural Consequences

  • Poor Decision-making: Being on hallucinogens affects your judgement. You might make risky decisions, like having unprotected sex or sharing drug paraphernalia, which can lead to long-term consequences like STDs or infections.
  • Addiction and Dependency: Most hallucinogens are not considered physically addictive, but you can become psychologically dependent on them. This means you might feel a strong urge to keep taking them, even if they’re causing harm. Psychological dependence can be just as hard to break as physical addiction.

Legal Ramifications

  • Criminal Charges: In many places, it’s illegal to have, sell, or make hallucinogens. If you’re caught, you could end up in jail, face heavy fines, or both. This can have a long-lasting impact on your life, making it harder to get a job or find housing.

Social Consequences

  • Relationship Strain: Using hallucinogens can cause problems in your relationships. Friends and family might not understand or appreciate your altered state of mind, and your unpredictable behaviour can put a strain on these relationships.
  • Occupational Risks: If you’re using hallucinogens regularly, it could affect your job performance. You might miss work, make mistakes, or even lose your job, which could lead to financial troubles down the line.

Long-Term Health Risks

  • Cognitive Decline: Long-term use of hallucinogens can mess with your brain. You might have trouble remembering things, find it harder to solve problems, or have difficulty concentrating.
  • HPPD (Hallucinogen Persisting Perception Disorder): This is a rare but serious condition where you keep experiencing hallucinations even after the drug has left your system. This can make it difficult to carry out everyday tasks and can severely impact your quality of life.

Interactions with Other Substances

  • Polydrug Use: Mixing hallucinogens with other drugs or alcohol can be very dangerous. The effects can be unpredictable, and the combination could increase your risk of overdose or other severe health problems.
  • Understanding these dangers in depth is crucial for anyone considering using hallucinogens. The risks are significant and wide-ranging, affecting all aspects of life from personal health to social interactions and legal standing.

Legal Status of Hallucinogen Drugs in the UK

The legal status of hallucinogen drugs in the UK is subject to a multifaceted structure of laws and regulations that aim to oversee their use, possession, distribution, and manufacture. This legal framework balances the therapeutic potential of certain hallucinogens against the risks tied to misuse, abuse, and dependence.

Regulation of Prescription Hallucinogens

  • Controlled Substances: Prescription hallucinogens, such as certain forms of ketamine, are governed by the Misuse of Drugs Act 1971, the Medicines Act 1968, and the Psychoactive Substances Act 2016. These acts stipulate the requirements for the prescription and dispensation of these drugs.
  • Scheduling System: Hallucinogens are classified into different classes (A, B, C) based on their abuse potential and medical utility. For instance, LSD is a Class A drug, reflecting its high abuse potential and limited recognised medical use.
  • Prescription Regulations: Medical professionals must adhere to stringent guidelines when prescribing hallucinogens, including providing detailed medical justification and securing approval from regulatory bodies.

Illicit Hallucinogen Laws and Penalties

  • Prohibition and Criminalisation: Illicit possession, distribution, or manufacture of hallucinogens is illegal under the Misuse of Drugs Act 1971. Drugs like LSD and magic mushrooms fall under Class A, attracting the most severe legal repercussions.
  • Penalties: The penalties for unlawful possession, distribution, or production of hallucinogens can be grave, encompassing fines, imprisonment, or both. The severity of the punishment depends on the class of the drug and the nature of the offence committed.

Understanding the legal landscape surrounding hallucinogen drugs in the UK is imperative for individuals, healthcare providers, and communities. This legal framework aims to manage the use of hallucinogens in a manner that minimises risks while recognising any potential therapeutic applications.

Harm Reduction and Safe Use Guidelines for Hallucinogen Drugs

Navigating the realm of hallucinogen drugs necessitates a comprehensive understanding of harm reduction and safe use practices. These guidelines are crucial for reducing the risks associated with hallucinogen use and fostering a culture of safety and responsibility, whether the drugs are used for medical or recreational purposes.

Dosage and Frequency Guidelines

  • Medical Use: For hallucinogens such as psilocybin that are being researched for therapeutic purposes, it is imperative to adhere strictly to clinical dosage and frequency guidelines. Deviation can result in unexpected psychological effects or dependency.
  • Recreational Use: Those who opt for recreational use should thoroughly understand the potency and effects of hallucinogens to avoid unintended outcomes like overdose or protracted perceptual changes.

Safe Use Practices

  • Drug Mixing: It is essential to avoid combining hallucinogens with other substances, including alcohol and stimulants, as this could lead to dangerous interactions and intensified effects.
  • Route of Administration: Opting for safer consumption methods, such as oral ingestion instead of injection, can diminish the risk of adverse effects and infections.
  • Purity and Source: Being knowledgeable about the purity and source of the hallucinogen is invaluable in assessing the risks associated with its use.
  • Clean Equipment: Employing sterile equipment to administer the drug can prevent the risk of bacterial infections or the transmission of diseases.

Resources for Help and Support

  • Addiction Treatment Centres: Several institutions offer help for those grappling with dependency on hallucinogens.
  • Community Support Groups: Participating in support groups can provide a beneficial network of mutual understanding and aid during the recovery phase.
  • Online Forums: These platforms offer spaces for individuals to share their experiences, seek counsel, and find support in their quest for safe hallucinogen use or recovery.

Safer Consumption Tips

  • Start with a Small Dose: When using a new substance or source, it’s safer to start small to assess bodily reactions.
  • Stay Hydrated and Nourished: Adequate hydration and nutrition can mitigate some of the negative effects of hallucinogen use.
  • Rest and Recovery: Allowing adequate intervals between uses is vital to stave off the build-up of detrimental effects.

By closely adhering to these harm reduction and safe use guidelines, individuals can markedly lessen the risks and potential harm associated with the use of hallucinogens, contributing to a safer community.


In conclusion, hallucinogens represent a diverse and complex class of psychoactive substances that have captured human interest for millennia. These drugs can profoundly alter human consciousness, affecting perception, emotion, and cognition. From their historical roots in spiritual and shamanic rituals to their more recent roles in scientific research and recreational use, hallucinogens remain a subject of intrigue, debate, and ongoing study.

The potential therapeutic applications of hallucinogens are equally compelling. Preliminary research suggests that substances like psilocybin and LSD may have therapeutic value in treating conditions like depression, anxiety, and PTSD. However, these potential benefits must be carefully weighed against the risks of misuse, dependence, and often unpredictable psychological effects.

Legal frameworks, such as the UK’s Misuse of Drugs Act 1971, aim to control the use of these substances due to their potential for abuse and the risks associated with their use. Yet, there is a growing movement advocating for a re-evaluation of these laws to facilitate medical research and potentially redefine these substances as therapeutic agents.

Overall, hallucinogens are far from being fully understood, either scientifically or socially. They hold a mirror to the complexities of the human mind, challenging our understanding of consciousness, reality, and the boundaries of human experience. As research advances, our perception of these substances and their societal role will likely continue to evolve. Still, for now, they remain a complex enigma that elicits both caution and curiosity.


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Hallucinogens are a class of drugs that alter perception, thoughts, and feelings, leading to hallucinations, or experiences where people perceive things that are not real.

Hallucinogens primarily affect the neurotransmitter serotonin, which plays a role in regulating mood, sensory perception, sleep, hunger, and more.

The legality varies by country. In the UK, most hallucinogens are Class A drugs under the Misuse of Drugs Act of 1971, making them illegal to possess, distribute, or produce.

Some hallucinogens like psilocybin are under research for treating conditions like depression and PTSD. However, these are not yet widely accepted medical treatments.

Risks include impaired judgment, anxiety, paranoia, and, in extreme cases, psychosis.

Overdose is generally rare but can happen, especially when mixed with other substances

While not considered physically addictive, psychological dependence is possible.

Duration depends on the type of hallucinogen and the dose, but effects can last from a few hours to several days

LSD is often called “Acid,” psilocybin mushrooms are known as “Magic Mushrooms” or “Shrooms,” and MDMA is commonly referred to as “Ecstasy” or “Molly.”

These include using tested substances, taking measured doses, avoiding mixing with other substances, and having a sober “sitter” to supervise the experience.

What to do in an emergency

If you or a someone else requires urgent help after consuming alcohol or drugs, do not hesitate – call 999 immediately and speak to a person trained to assist you. It could be the difference between life and death.