Hallucinogens Flashcards
What is another term used to describe hallucinogens?
Psychedelics
Define hallucinogens
Change the way people see, hear, taste, smell or feel, and affect mood and thought
What are the two main categories of hallucinogens?
Psychedelics and dissociatives
What are reported effects of hallucinogens?
Auditory, visual and sensory hallucinations
Distorted perceptions
Difficulty distinguishing between reality and illusion
Paranoia
Psychosis
What are traditional hallucinogens?
Plant compounds that have been used for hundreds-thousands of years in spiritual ceremonies
How do traditional hallucinogens act?
Via 5-HT (serotonin) receptors
What is mescaline?
Found in several cactus species (e.g., peyote cactus), native to southwestern US and Mexico
Used for thousands of years in religious ceremonies
What receptors does mescaline have affinity for?
High - 5-HT2A
Some - 5-HT2B
Describe the structure of mescaline.
Substituted phenethylamine
What does the amanita muscaria mushroom contain?
ibotenic acid and muscimol
Describe the interactions that are thought to cause the psychoactive effects of amanita muscaria
Muscimol is a potent GABA A agonist
Ibotenic acid is an NMDA glutamate receptor agonist
What are magic mushrooms?
Mushrooms that contain alkaloids with hallucinogenic properties
What is the pharmacologically significant ingredient in magic mushrooms?
Psilocybin
What is psilocybin?
A pro-drug that is dephosphorylated by alkaline phosphatase to psilocin
Describe how psilocybin works in the body.
Partial agonist for 5-HT2B and 5-HT2C
Slightly lower affinity for 5-HT2A
Some effects on dopamine but no direct action
Describe the case of R v Chan
Took magic mushrooms
Attacked and killed father with knife
Defence of automatism and underlying brain injury
How was LSD discovered?
By Albert Hoffmann, research chemist experimenting with alkaloids of ergot (rye fungus)
Compare LSD and mescaline
Similar early descriptions
LSD 5,000 - 10,000 times stronger
How is LSD absorbed?
Easily absorbed via oral admin
Describe how LSD works in the body.
Acts on 5-HT2A receptors in the brain
Has some effects on the dopamine D2 receptor
What is the potency of LSD?
1 dose is 20-80 ug.
Describe LSD blotters
LSD dissolved in water, single-dose drops applied to a sheet of paper (blotter) and dried
Paper divided into tabs
Each sheet typically contains 100 doses
What are potential effects of LSD?
Vivid visual hallucinations
Slowing of the subjective sense of time
Feelings of depersonalization
Strong emotional reactions
Disruption of logical thought
Synesthesia
What is synesthesia?
Crossing-over of sensations in which, for example, colours are heard and sounds are felt
Differentiate between good and bad LSD trips
Good - mystical, spiritually enlightening
Bad - disturbing, frightening
What does a good or bad trip depend on?
Dose
Individual
Environment
What are substituted phenylethylamines?
Chemical class of organic compounds based upon the phenethylamine structure.
Many are psychoactivr
Describe the structure of phenethylamine hallucinogens.
Catecholamine-like
Describe the structure of mescaline
Similar to NE and amphetamine
What receptors do phenylethylamines bind to?
Some 5-HT receptors
What are flashbacks?
Re-experiencing one or more perceptual effects after the drug has worn off - months or years later
What is HPPD?
Hallucinogenic persisting perception disorder
Is listed in DSM-V
What is the most severe adverse effect of hallucinogens?
Psychotic reaction
Who is generally affected by prolonged psychotic episodes?
Those who have already been diagnosed with a psychotic disorder or who had a preexisting risk for developing psychosis
Describe the case of the Oak Ridge facility.
Experimental forms of therapy
Gave high doses of hallucinogens and mind-altering drugs, including LSD
Some groups of naked men locked in rooms for up to 11 days
What are some potential therapeutic treatments using hallucinogens?
OCD
PTSD
Alcoholism
Depression
Anxiety
What are dissociative anesthetics?
Subcategory of hallucinogenic drugs
Don’t have the same mechanism of action as many classic hallucinogens
Give examples of dissociative anesthetics
Ketamine
Phencyclidine (PCP)
Dextromethorphan
Describe the first usage of dissociative anesthetics
First developed as a safer alternative to typical general anesthesia
Not associated with respiratory depression
PCP had unacceptable side effects so did not enter routine clinical use
Ketamine developed - still had some side effects but less severe
What can dissociative anesthetics often produce?
Visual and auditory distortions and a sense of floating and dissociation
Describe effects of dissociative anesthetics in low/moderate doses.
Numbness
Disorientation
Changes in sensory perceptions
Hallucinations
Feelings of detachment from self
Dizziness
Describe effects of dissociative anesthetics at high doses.
Hallucinations
Memory loss
Extreme panic, fear, anxiety
Paranoia
Aggression
How do dissociative anesthetics work?
NMDA receptor agonists
NMDA receptor is an important inotropic receptor for glutamate
Ionotropic receptors directly open ion channels that enable specific ions to stream in and out of the cell, leading to firing of the neuron
Non-competitive atagonists
What is a non-competitive antagonist?
Bind to different part of receptor but still stops the binding of neurotransmitters
What are possible routes of administration for PCP?
Oral
Intranasal
IV
Smoked (sometimes in regular cigs)
What is the half-life of PCP?
7 - 46 hours
What is important to keep in mind about drug-related media reports?
Drug use is often based on anecdotal evidence
It is unusual for an accused individual to have drug testing done shortly after the crime
Analysis of drugs found at scene is not always one
Are illicit drugs reliable?
Why/how is ketamine important?
Used in hospitals during surgery and during emergency treatment
On the WHO list of essential medicine
Low toxicity
What are some therapeutic uses of ketamine?
Anesthesia in children
Asthmatics or people with chronic obstructive airway disease
Surgery in field conditions/war zones
Widely used in animal surgery
How is ketamine classified?
Club drug
What is another name for ketamine?
K-hole
What are possible administration routes for ketamine?
Oral
Intranasal
IM
What is the half-life of ketamine?
2 hours
What are some subjective experiences reported by ketamine users?
Light sensations coming through the body
Bizarre distortions of body shape and time
Sensations of floating or hovering weightlessly in space
Feeling of leaving one’s body
Complete loss of time sense
What is dextromethorphan?
OTC cough medication
What do therapeutic doses of dextromethorphan act as?
Antitussive agent
What happens to dextromethorphan at higher doses?
Metabolized to dextrophan
What kind of agonist is dextromethorphan?
NMDA receptor agonist
What is the half-life of dextromethorphan?
3 hours but up to 40 in slow metabolizers
Why is dextromethorphan abused so widely?
Wide availability
What is the standard dose of dextromethorphan for cough suppression?
20 mg
What are recreational doses of dextromethorphan?
Can be 1000 mg (up to 2 bottles)
Describe the case of R. v. Doodnaught.
Anesthesiologist
Found guilty of SAing 21 women under surgery from 2006-2010
One of first complainants was told by head anesthesiologist that it couldn’t have happened and she hallucinated the whole experience
