forensics lecture 3- drugs

Question 1

what is pharmacodynamics?

Answer 1

The study of the dose versus pharmacological response

Question 2

what is pharmacokinetics?

Answer 2

The study of the ADME processes over a period of time
Absorption, Distribution, Metabolism & Elimination

Question 3

what is pharmacogenetics?

Answer 3

The study of genetic influences/variances on the ADME processes

Question 4

what is forensic toxicology?

Answer 4

Study of the effects of alcohol, drugs or poisons with application to the law.
-Post-mortem toxicology
-Human performance
-Drug testing (workplace/sports)

Question 5

what are the types of toxicology cases?

Answer 5

-Road Traffic Act offences
-Drink driving
-Drug driving
-Drug-facilitated sexual assault
-Hair testing for social services
-Sudden or suspicious deaths

Question 6

what is paracelsus’ third defence?

Answer 6

Dosis facit venenum

-“What is there that is not poison?
All things are poison and nothing without poison.
Solely the dose determines that a thing is not poison.”

Question 7

what are types of class A drugs>

Answer 7

-Major natural and synthetic opiates
-cocaine and crack cocaine
-LSD
-injectable amphetamines
-Cannabinol
-Magic mushrooms
-Ecstasy

Question 8

what are types of class B drugs?

Answer 8

-Oral Amphetamines
-Cannabis plant material and resin
-Codeine, Dihydrocodeine
-Certain barbiturates

Question 9

what are types of class C drugs?

Answer 9

-Benzodiazepines
-Methaqualone
-Gamma Hydroxybutyrate (GHB)
-Ketamine

Question 10

what information can we get from the analysis of drugs?

Answer 10

-Qualitative/quantitative
-Bulk/Trace
-Chronic/Acute
-Screening
-Confirmation
-Targeted analyses

Question 11

what are the methods of analysis of drugs?

Answer 11

-Presumptive tests
-Thin Layer Chromatography
-Column Chromatography
-HPLC
-Gas Chromatography
-Mass Spectrometry
-Immunoassay
-Spectroscopy

Question 12

how do we use hair to analyse drug use?

Answer 12

-Drugs bind to melanin – weak bases
-Heat/volatise to smoke (Uncharged/free base) – nicotine, cocaine, heroin
-Hair grows 0.35mm/day 1cm/month
-Metabolites can also be detected – this identifies drugs coming from the body.

Question 13

how does workplace drug testing occur?

Answer 13

Core drug groups: Cannabis, Cocaine, Amphetamines, Opiates

Testing: Saliva, Urine, Hair

Question 14

what is amphetamines and its effects?

Answer 14

Methamphetamine – stimulant

Administration: Inhalation, oral, snorting, injection
Action: Increased dopamine

Effects:
-increased wakefulness and physical activity
-decreased appetite
-faster breathing
-rapid and/or irregular heartbeat
-increased blood pressure and body temperature
Long term effects:
-HIV/AIDS
-Weight loss
-Severe dental problems (“Meth mouth”)

Question 15

what is ecstasy and what are the effects of the drug?

Answer 15

Ecstasy (Molly and MDMA)
Chemically similar to stimulants/hallucinogens

Increase in activity of:
Dopamine – Euphoria & increased energy/activity
Norephinephrine – Increased heart rate & blood pressure
Other effects: nausea, muscle cramping, blurred vision
Effects last 3-6 hours
High doses affect temperature regulation
Psychotherapy?

Question 16

what is cocaine and what are the effects of the drug?

Answer 16

Extraction from cocoa leaf/ chemical synthesis
Administration : SNORTING, injection, oral
Stimulant: Increases levels of dopamine

Short-term health effects of cocaine include: extreme happiness and energy , mental alertness, hypersensitivity to sight, sound, and touch , irritability, paranoia

Other health effects of cocaine use include: constricted blood vessels , dilated pupils, nausea, raised body temperature and blood pressure, faster heartbeat, tremors and muscle twitches, restlessness

Question 17

what is heroin and what are the effects of the drug?

Answer 17

Active ingredients :Diamorphine, other opiates e.g. codeine
Names: Smack, horse, brown
Administration: Smoking (chasing the dragon), IV
Legislation: Class A

Effects:
Analgesia, Dreamy euphoria, Sedation, Respiratory depression Nausea and vomiting, Cough suppression, Constipation

Question 18

what are LSD (Lysergic Acid Diethylamide) and what are the effects of the drug?

Answer 18

Hallucinogen synthesised from Lysergic acid
Microdots/ blotter acids
Dosage 50 -300mg (20-25mg sufficient)
Affects the actions of brain chemical glutamate (NMDA receptors) /seretonin

Rapid emotional swings; distortion of a person’s ability to recognize reality, think rationally, or communicate with others; raised blood pressure, heart rate, body temperature; dizziness and insomnia; loss of appetite; dry mouth; sweating; numbness; weakness; tremors; enlarged pupils.

Question 19

what is cannabis and what are the effects of the drug?

Answer 19

Names: Pot, weed, hash, grass, dope
Administration: Smoking, dabbing, food
Legislation: Depends on preparation
- Cannabis plant and resin (Class B), oil (Class A)

Effects: Euphoria, Nausea, Hypotension, Bloodshot eyes, Poor coordination, distortion, Munchies
Speed depends on method of administration (smoking = minutes, oral ~ 1 hour)

Question 20

what are benzodiazepines?

Answer 20

Prescription drugs
Street names: Moggies, jellies
Administration: Oral, injection
Actions: Depressants – reduce tension and anxiety, drowsiness

Flunitrazepam – “date rape”

Question 21

what do drugs cause?

Answer 21

-Fatal Poisoning
-suicide
-accident
-industrial
-homicide
-iatrogenic

Question 22

what are the 5 factors affecting toxicity?

Answer 22

Dose Response curve: LD50 – ½ Maximum response

Sensitisation: Second time may have enhanced immune response

Tolerance: When repeatedly exposed

Accumulation: Long half-life

Bioavailability: Proportion of original dose absorbed and rate absorption takes place