Lecture 18: Major Drugs and Forensic Toxicologist Flashcards
When was marijuana was introduced to the Caribbean and by who?
In 1838 by workers of India.
Why was the habit was taken on by the working class?
The habit was taken on by the working class as it was stated that marijuana increased morale and production.
Marijuana contain numerous compounds called
Marijuana contain numerous compounds called cannabinoids.
Cannabis contains over ______ chemical compounds and how many are classified as cannabinoids
Cannabis contains over 400 different chemical compounds and 85 are currently classified as cannabinoids
The group that contains the compound of interest,
tetrahydrocannabinol, commonly called THC.
Cannabinoids are a class of diverse chemical compounds that act on
the cannabinoid receptors in cells that repress neurotransmitter release in
the brain.
Ligands for these cannabinoid receptor proteins include:
- Endocannabinoids
- Phytocannabinoids
- Synthetic cannabinoids
WHat are Endocannabinoids ligands?
Endocannabinoids - produced naturally in the body by humans and
animals
What are phytocannabinoids?
Phytocannabinoids - found in cannabis and some other plants
What are Synthetic cannabinoids?
Synthetic cannabinoids are manufactured artificially.
The most notable cannabinoid is
The most notable cannabinoid is the phytocannabinoid tetrahydrocannabinol (THC),
The primary psychoactive compound of cannabis
Cannabidiol (CBD) is another major constituent of the plant.
What is the most psychoactive compound in marijuana?
THC the most psychoactive compound inmarijuana
How much percentage THC makes up the cannabinoid family.
THC constitutes 30% of the cannabinoid family.
THC is also known as
It is also known as delta-9-tetrahydrocannabinol (Δ9-THC).
THC was extracted by a team headed
by Dr. Raphael Mechoulam in 1964
What is the mechanism of THC?
Its mechanism involves its binding to the CB1 and CB2, which are cannabinoid receptors.
Is THC an agonist, antagonist or partial agonist
THC acts a partial agonist.
Cannabinoid receptors in the brain involved in a variety of physiological processes including
- Appetite,
- Pain-sensation
- Mood
- Memory.
When can THC be administered intravenously?
THC can be administered intravenously , however that is usually done under psychological clinical trial.
What is THC metabolised to in the human body
THC is metabolized mainly to 11-OH-THC (11-hydroxy-THC) by the human body.
11-OH-THC (11-hydroxy-THC) metabolite is oxidized to?
This metabolite (byproduct of metabolism) is still psychoactive and is further oxidized to 11-Nor-9-carboxy-THC (THC-COOH
How much of THC is excreted in the faeces and in the urine.
More than 55% of THC is excreted in the faeces and ~20% in the urine.
The main metabolite in urine is
The ester of glucuronic acid and THC-COOH and free THC- COOH.
Psychological effects of THC
Effect on mood - decreased anxiety, alertness, depression, tension and increased sociability
* Effects on perception – Vivid colours, clear music, meaningful emotions
* Effects on cognition and psychomotor performance – slow reaction time
* Driving and piloting skills – impaired driving similar to alcohol
What are the tolerance, dependence, withdrawal effects
restive, anxiety, aggression, insomnia
Systemic effects of THC
- Cardiovascular effects – Dose related tachycardia – heart rate that exceeds the normal range
- Effects on the respiratory system – 1/3 more tar than cigarette, linked to bronchitis
What is Hash oil?
Hash oil is cannabis concentrate containing many of its resins and terpenes – in particular, tetrahydrocannabinol, cannabidiol, and other cannabinoids.
What is Hashish?
Hashish is the potent form of cannabis produced by collecting and compressing
trichomes, the most potent material from cannabis plants.
Medicinal Effects of Marijuana?
- Control of nausea
- Appetite stimulant
- Reduction in ocular pressure (treatment of glaucoma)
- Anti-asthma
- Pain relief
Marijuana related drugs on-the-market:
Canasol (glaucoma) & Asmasol (anti asthma)
Drug testing cutoff levels -
minimum concentrations of drugs or metabolites that must be present in specimens, before labs will report the drug testing results as positive
Urine Preliminary Immunoassay Cut off
50ng/mL…this level equates to a daily user remaining positive for approx. 7-30 days post cessation.
Urine Preliminary GCMS Cut off
15ng/mL…this level equates to the frequent user being positive for e.g. 15 weeks
Oral fluid cut off level
- 4 µg/L
Sweat cutoff level
- 4 ng/patch
What is drug dependence?
Drug dependence refers to the action of an individual becoming strongly attached to a drug.
Dependency is subdivided into two categories
- Physiological dependence
- Psychological dependence
Physiological dependence occurs when
Physiological dependence occurs when there is a need by the body to have the drug present. In this case person may experience sickness if they stop taking the drug.
Psychological dependence occurs when
Psychological dependence occurs when a person develops an uncontrollable “craving” (mental or emotional need) for a drug. Craving is a desperate need to continue.
Stimulants are
Stimulants are drugs that stimulate the brain and central nervous system, speeding up communication between the two.
Common stimulants include:
Common stimulants include:
o Crack
o Cocaine
o Amphetamines
o Metamphetamines
How does stimulants work?
They increase alertness and physical activity and increase the amount of dopamine which is a neurotransmitter responsible for feelings of pleasure resulting in euphoria.
Depressants are
Depressants are drugs that slow down the activity of the brain and nervous system, slowing down the communication between the two.
user of depressant drug may experience:
Slowed heartbeat , reduction in anxiety, and in some cases the
promotion of sleep
Examples of depressant?
This drug class includes:
o Barbiturates
o tranquilizers
o sleep acids
o ethanol
Hallucinogens interfere with the
brain and central nervous system in a way that results in radical distortions of a user’s perception of reality
Two classes of Hallucinogens
o Phenethylamine - Methamphetamine and ecstasy
o Tryptamine – Psiclobin
Common Hallucinogens include:
o Marijuna
o Psilocybin
o Ketamine
o Mescaline
Common Alcohols of Interest
Methyl Alcohol (Methanol)
Ethyl Alcohol (Ethanol)
Isopropyl Alcohol (Isopropanol)
Ethylene Glycol (Antifreeze)
Methyl Alcohol (Methanol) (Wood Alcohol) use
Primarily for commercial and industrial purposes and
also as a solvent in paints, paint remover, varnishes.
Ethyl Alcohol (Ethanol) (Grain Alcohol) use
BEVERAGE SOLVENT; MEDICINAL VEHICLE
Isopropyl Alcohol (Isopropanol) (Rubbing Alcohol) use
DENATURANT; ANTISEPTIC
Ethylene Glycol (Antifreeze) use
COOLANT; SOLVENT
What is Methanol?
Methanol, sometimes called wood alcohol or wood spirits, has no therapeutic properties
Methanol in Consumer Products
Gas-line antifreezes (99-100% v/v)
Windshield washer fluids (17-95%
Duplicating fluids (60-90%)
Paint removers (3-50%)
Model airplane fuels (43-77%)
Carburator fluids (1-38%)
Ethanol denaturants (2-5%)
Solid can fuels (<4%)
Glass cleaners (1-40%)
Metabolic acidosis
A condition that occurs when the body produces too much acid or when the kidneys do not remove enough acid from the body.
If unchecked, metabolic acidosis leads to
academia.
Metabolic acidosis causes are diverse, and its consequences can be
It causes are diverse, and its consequences can be serious, including coma and death.
Methanol poisoning causes
nausea, abdominal pain, lethargy, confusion
Severe methanol poisoning progresses to
anion-gap metabolic acidosis, coma, seizure, and respiratory/circulatory failure
Lactic acid accumulation has been observed in methanol poisoned patients as a result of
methanol-induced hypotension.
In methanol poisoning, metabolic acidosis may necessitate
the administration of bicarbonate and assisted ventilation.
Bicarbonate potentially may
reverse visual deficits and help to decrease the amount of active formic acid.
Antidote therapy, which frequently involves the use of ethanol or 4-methyl pyrazole (fomepizole), is aimed at
delaying methanol metabolism until the methanol is eliminated from the patient’s system, either naturally or through dialysis.
Like methanol, ethanol is metabolized
by ADH, but the enzyme’s affinity for ethanol is 10-20 times higher than it is for methanol.
Fomepizole is also metabolized
by ADH; however, its use is limited because of high cost and lack of availability
Isopropanol is used in
some rubbing alcohol (70-90 %v/v), ethanol denaturants (5%), deicers (70-80%), glass cleaners (1-14%), liquid detergents (5-12%), cements (5-20%), paint strippers (2-11%), paint thinners (5-10%)
Isopropanol is metabolized to
Metabolized to acetone (CNS depressant)
How long is isopropanol half life compared to ethanol?
Longer t1/2 than ethanol
Ethylene Glycol half life
t½ = 3 h
Ethylene Glycol Sources
- Automotive products (antifreeze, windshield de-icers, coolants)
- Detergents
- Paints
- Polishes
- Cosmetics
- Improperly added preservatives to juices and wines
Ethylene Glycol Sources
- Automotive products (antifreeze, windshield de-icers, coolants)
- Detergents
- Paints
- Polishes
- Cosmetics
- Improperly added preservatives to juices and wines
Ethanol lethal dose
adults 5-8 g/Kg & children 3 g/Kg
Alcohol Content of 12oz Beer and Malt Beverages
3.5-8% ethanol*
Alcohol Content of 6oz Wine
8-14% ethanol
Alcohol Content of 1.5 oz Hard Liquor
35 to 55% ethanol (70 to 110 proof)
Calculate Ethanol Content of Beverage
Grams of Ethanol = F x V x 0.79 (g/mL)
F = fraction of ethanol (%v/v)
V = volume in mL (1 oz. = approx. 30 mL)
0.79 = ethanol specific gravity (gm/mL at 20ºC)
Absorption of Alcohol
- Simple Diffusion
- Concentration gradient dependent
- Non-linear process
- Uses aqueous channels
- Distributes in proportion to water content
Factors Affecting Absorption
- Gastric emptying
- GI mobility and blood flow
- Beverage alcohol conc.
- Concentration gradient
What is cocaine
Coca is widely cultivated
in Bolivia, Peru and Ecuado
The lead producer of cocaine is
Colombia, currently the source of about 80% of the world’s cocaine.
CHEMICAL NAMES for Cocaine
- Benzoylmethylecgonine
- (1R,2R,3S,5S)-2-Methoxycarbonyltropan-3-yl benzoate
- 2ß-carbomethoxy-3ß-benzoxytropane
- 1aH, 5aH-tropane-2ß-carboxylic acid 3ß-hydroxy-methyl ester benzoate
- 3-tropanylbenzoate-2-carboxylic acid methyl ester
- 3-(benzoyloxy)-8-methyl-8-azabicyclo-(3.2.1.) octane-2-carboxylic acid methyl ester
Street Names of Cocaine
Bernice; Bernies; Blow; Burese; C; Cadillac of drugs; Carrie; Cecil; Champagne of drugs; Charlie; Cholly; Coke; Corine; Crack; Dama blanca; Eritroxilina; Flake; Girl; Gold dust; Green gold; Happy dust; Happy trails; Her; Jam; Lady; Leaf; Nose candy; Pimp’s drug; Rock; She; Snow; Star dust; Star-spangled powder; Toot; White girl; White lady; Liquid lady (alcohol + cocaine); Speed ball (heroine + cocaine)
Acute Cocaine progresses through three phases
- Early stimulation
- Advanced stimulation
- Depression
Early stimulation phase of acute cocaine
- Excitement, enlarged pupils, euphoria, agitation, irritability, bruxism, twitching, psychosis, elevated temperature, elevated pulse
Advanced stimulation phase of acute cocaine
Convulsions, seizures, hyper-reflexia, diminished consciousness, increased blood pressure, hyperthermia
Depression phase of acute cocaine
Paralysis, loss of reflexes, respiratory depression, coma, cardiovascular/circulatory collapse, cardiac arrest, death
Medicinal Use of Cocaine
Nasal Surgery
Cocaine and Driving
- Increased risk taking behavior
- Sensory abilities
- Visual impairment
- Motor coordination
- Attentional abilities
- Cognitive abilities
- Post high “crash”
