L2 Forensics Drugs Dr Peter Moult 23_24

University of Glasgow Toxicology Overview

  • Course: Drugs 2 0 FOR You

  • Instructor: Dr. Peter Moult

  • Contact: Peter.Moult@glasgow.ac.uk

  • Location: Sir James Black Building 341

Lecture Aims

  • Explain the effects of alcohol and clearance from the human body

  • Describe how alcohol concentrations are determined

  • Explain the effects of drugs of abuse and prescription drugs

  • Describe drug detection methods in the body

Pharmacology Concepts

Pharmacodynamics

  • Defined as "what the drug does to the body"

  • Studies biochemical, physiological, and molecular effects

  • Involves receptor binding, post-receptor effects, and chemical interactions

Pharmacokinetics

  • Defined as "what the body does to a drug"

  • Refers to the absorption, distribution, metabolism, and elimination (ADME) of drugs

  • Describes the movement and time course of drugs in the body

Forensic Toxicology

  • The study of alcohol, drugs, or poisons with legal applications

  • Areas of focus:

    • Post-mortem toxicology

    • Human performance evaluation

    • Drug testing in workplace and sports

  • Objectives of a forensic toxicologist include determining whether substances played a role in a death or crime

Types of Toxicology Cases

  • Road Traffic Act offences

  • Drink driving and Drug driving incidents

  • Drug-facilitated sexual assault cases

  • Hair testing for social services

  • Investigation of sudden or suspicious deaths

Paracelsus’s Third Defence

  • "Dosis facit venenum"

  • Meaning: The dose determines whether a substance is a poison

Controlled Substances Overview

  • Any drug subject to the Misuse of Drugs Act 1971

  • Issues include fatal poisoning, suicide, accidents, industrial incidents, homicide, and iatrogenic effects

Drugs of Abuse Classification

Class A

  • Includes major natural and synthetic opiates, cocaine and crack cocaine, LSD, injectable amphetamines, cannabinol, magic mushrooms, ecstasy

Class B

  • Includes oral amphetamines, cannabis, resin, codeine, dihydrocodeine, and certain barbiturates

Class C

  • Includes benzodiazepines, methaqualone, GHB, and ketamine

Analysis of Drugs

  • Techniques include qualitative, quantitative, screening, and confirmation methods

  • Types of analyses: bulk/trace, chronic/acute

  • Methods of analysis:

    • Presumptive tests

    • Thin Layer Chromatography

    • Column Chromatography

    • High-Performance Liquid Chromatography (HPLC)

    • Gas Chromatography

    • Mass Spectrometry

    • Immunoassay

    • Spectroscopy

Hair Analysis

  • Drugs can bind to melanin; weak bases such as nicotine and cocaine can heat/volatize

  • Hair grows approximately 0.35mm/day; can detect metabolites indicating drug use

Workplace Drug Testing

  • Details on urine and hair testing methodologies and the substances screened

  • Includes guidelines for specific thresholds of various drugs in the workplace

Pharmacology Highlights

Pharmacokinetics and Pharmacodynamics

  • ADME processes; relationship of dose versus pharmacological response

Pharmacogenetics

  • Studies genetic influences/variances on ADME

Factors Affecting Toxicity

  • Understanding dose-response curves, including LD50 statistics

  • Concepts of sensitization, tolerance, accumulation, and bioavailability

Major Drugs of Abuse

Amphetamines

  • Increased dopamine levels; effects include increased activity, appetite suppression, rapid heartbeat

  • Long term: risk of severe dental issues and HIV/AIDS

Ecstasy (MDMA)

  • Similar to stimulants; effects include euphoria and possible risks to temperature regulation

Cocaine

  • Administration through snorting, injecting, oral; effects include heightened energy and mental alertness

Heroin

  • Known for its sedative effects alongside risks of respiratory depression

LSD

  • A hallucinogen causing emotional swings and perception distortion

Cannabis

  • Varying effects based on administration method; includes euphoria and potential for consumption time variation

Benzodiazepines

  • Used as depressants; street names include "moggies" and "jellies"

Summary/Key Points

  • Role of toxicology in forensics

  • Types of cases forensic toxicologists investigate

  • Understanding of the Misuse of Drugs Act

  • Familiarity with analytical techniques for drug detection

  • Awareness of effects and mechanisms of action of major drugs of abuse

Detailed Revision on Drugs of Abuse and Prescription Drugs Effects & Detection Methods

Intended Learning Outcomes

  1. Describe the Effects of Drugs of Abuse and Prescription Drugs

    • Drugs of Abuse

      • Amphetamines

        • Effects: Increased dopamine levels lead to increased activity, appetite suppression, and rapid heartbeat.

        • Long-term effects: Risk of severe dental issues, possible HIV/AIDS transmission due to risky behavior.

      • Ecstasy (MDMA)

        • Effects: Euphoria and emotional connection but potential risks include hyperthermia, dehydration, and serotonin syndrome.

      • Cocaine

        • Administration routes: Snorting, injecting, or orally.

        • Effects: Heightened energy, mental alertness, and elevated mood; risks of addiction and severe cardiovascular issues.

      • Heroin

        • Effects: Sedative effects, immediate euphoria followed by sleepiness, but risk of severe respiratory depression and dependence.

      • LSD

        • Effects: Distorted perception, emotional swings, risk of flashbacks and persistent perception disorder.

      • Cannabis

        • Effects vary based on administration (smoking, edibles); includes euphoria, relaxation, and anxiety for some users.

      • Benzodiazepines

        • Effects: Anxiety relief, sedation; risk of dependency and overdose, especially when mixed with alcohol.

    • Prescription Drugs

      • Opioids (e.g., Oxycodone, Morphine)

        • Effects: Pain relief, euphoria, but high risk for addiction, respiratory depression, and overdose.

      • Stimulants (e.g., Adderall)

        • Effects: Increased concentration and alertness; can lead to anxiety and potential for abuse.

      • Benzodiazepines: As noted, prescribed for anxiety or insomnia, with risks of tolerance and dependence.

  2. Describe How Drugs are Detected in the Body

    • Methods of Drug Detection

      • Urine Testing

        • Commonly used for workplace drug testing; detects metabolites of substances.

        • Threshold levels set for specific drugs to determine positive results.

      • Hair Analysis

        • Capable of indicating drug use over long periods; drugs bind to melanin and can be detected for weeks to months.

        • Growth rate of hair: ~0.35mm/day provides a timeline for drug exposure.

      • Blood Testing

        • Provides immediate detection, showing real-time levels of a drug; often used in acute settings such as accidents.

      • Saliva Testing

        • Less common but useful for rapid, on-site testing; provides a shorter window of detection compared to urine.

      • Sweat Testing

        • Newer method; sweat patches are worn to collect perspiration over time for drug analysis.

    • Analytical Techniques for Detection

      • Presumptive Tests: Initial screening methods to identify the presence of a substance.

      • Thin Layer Chromatography: Separates compounds for identification.

      • Gas Chromatography & Mass Spectrometry: Comprehensive analysis to confirm presence and quantify drugs.

      • Immunoassay: Commonly utilized for initial drug screening, especially in urine tests.

      • High-Performance Liquid Chromatography (HPLC): For detailed analysis, often in research or forensic contexts.

Detailed Revision on Drugs of Abuse and Prescription Drugs Effects & Detection Methods

Intended Learning Outcomes

  1. Describe the Effects of Drugs of Abuse and Prescription Drugs

    • Drugs of Abuse

      • Amphetamines

        • Effects: Increased dopamine levels lead to increased activity, appetite suppression, and rapid heartbeat.

        • Long-term effects: Risk of severe dental issues, possible HIV/AIDS transmission due to risky behavior.

      • Ecstasy (MDMA)

        • Effects: Euphoria and emotional connection but potential risks include hyperthermia, dehydration, and serotonin syndrome.

      • Cocaine

        • Administration routes: Snorting, injecting, or orally.

        • Effects: Heightened energy, mental alertness, and elevated mood; risks of addiction and severe cardiovascular issues.

      • Heroin

        • Effects: Sedative effects, immediate euphoria followed by sleepiness, but risk of severe respiratory depression and dependence.

      • LSD

        • Effects: Distorted perception, emotional swings, risk of flashbacks and persistent perception disorder.

      • Cannabis

        • Effects vary based on administration (smoking, edibles); includes euphoria, relaxation, and anxiety for some users.

      • Benzodiazepines

        • Effects: Anxiety relief, sedation; risk of dependency and overdose, especially when mixed with alcohol.

    • Prescription Drugs

      • Opioids (e.g., Oxycodone, Morphine)

        • Effects: Pain relief, euphoria, but high risk for addiction, respiratory depression, and overdose.

      • Stimulants (e.g., Adderall)

        • Effects: Increased concentration and alertness; can lead to anxiety and potential for abuse.

      • Benzodiazepines: As noted, prescribed for anxiety or insomnia, with risks of tolerance and dependence.

  2. Describe How Drugs are Detected in the Body

    • Methods of Drug Detection

      • Urine Testing

        • Commonly used for workplace drug testing; detects metabolites of substances.

        • Threshold levels set for specific drugs to determine positive results.

      • Hair Analysis

        • Capable of indicating drug use over long periods; drugs bind to melanin and can be detected for weeks to months.

        • Growth rate of hair: ~0.35mm/day provides a timeline for drug exposure.

      • Blood Testing

        • Provides immediate detection, showing real-time levels of a drug; often used in acute settings such as accidents.

      • Saliva Testing

        • Less common but useful for rapid, on-site testing; provides a shorter window of detection compared to urine.

      • Sweat Testing

        • Newer method; sweat patches are worn to collect perspiration over time for drug analysis.

    • Analytical Techniques for Detection

      • Presumptive Tests: Initial screening methods to identify the presence of a substance.

      • Thin Layer Chromatography: Separates compounds for identification.

      • Gas Chromatography & Mass Spectrometry: Comprehensive analysis to confirm presence and quantify drugs.

      • Immunoassay: Commonly utilized for initial drug screening, especially in urine tests.

      • High-Performance Liquid Chromatography (HPLC): For detailed analysis, often in research or forensic contexts.