Hallucinogens

Drugs that act on the central nervous system and produce marked changes in perception, thought and consciousness are called hallucinogens.

Hallucinogens are drugs that act on the central nervous system (CNS) and produce marked changes in perception, thought, and consciousness. They are also called psychedelic, illusionogenic, psychotomimetic, or mind-expanding drugs.

On perception and consciousness

• Alter consciousness, perception, and personality.
• Cause initial cerebral excitation, producing illusions, hallucinations, coloured visions, and unusual amusement or fear.
• Followed by intense cerebral depression.

On behaviour and judgement

• Impair memory, observation, and reasoning ability.
• Disorganise the sense of space and time, causing misjudgement of distances.
• This misjudgement can lead to accidents, such as tumbling down steps.

1. Chemically produced hallucinogens

• Main example: LSD (Lysergic Acid Diethylamide).
• Originally derived from ergot, a substance from Claviceps purpurea, a fungus that grows on rye and wheat.

2. Plant-derived hallucinogens

• Mescaline: obtained from peyote cactus buttons.
• Psilocybin and psilocin: found in Mexican mushrooms.
• Cannabis (Cannabis sativa): often classified as a hallucinogen.
• Other natural sources: morning glory seeds, jimson weed, and nutmeg.
• Note: Amphetamines and alcohol are not usually classified as hallucinogens but can produce hallucinations in large doses.

• Onset: about 40 minutes after oral intake.
• Duration: several hours.
• Characterised by highly coloured, rapidly changing images and dream-like or nightmare-like experiences, described as a temporary mental disorder.

Good trip vs. bad trip

Important note: the same drug's effects can differ markedly between individuals and even between occasions for the same person.

Tolerance

• Regular use of LSD, mescaline, and psilocybin induces tolerance within a few days.
• Normal sensitivity returns after several days of abstinence.

Health Risk

• LSD use by pregnant women is associated with an increased risk of spontaneous abortion.

• Hallucinogens act on the CNS and alter perception, thought, and consciousness.
• Two categories: chemically produced (e.g., LSD) and plant-derived (e.g., mescaline, psilocybin, cannabis).
• Effects: hallucinations, impaired judgement, disturbed sense of space/time.
• "Trip" lasts several hours and can be good or bad; effects vary by individual.
• Tolerance develops with repeated use; LSD carries pregnancy-related risk.