L1: Lecture_1_Intro_2026_HO__4_

  • Definitional Perspectives on "Drugs"

  • Oxford English Dictionary: "Any substance that affects the physical or mental functioning of a living organism."

  • World Health Organization (WHO): "Chemical entity, or mixture, other than those providing maintenance of normal health (e.g. food) that alters biological functioning."

  • Historical and Functional Categorizations (Tupper, 2012):     - Drug as Medicine ($15$th Century French/Spanish 'drogue/Droga'): A substance used in the prevention or treatment of disease, or a substance that has a physiological effect on a living organism.     - Drug as Psychoactive Substance ($17$th Century English): A chemical substance other than a food that alters consciousness when absorbed into the body, regardless of medical use or legal status.     - Drug as Dope or Narcotic (End of $1900$s International Control Treaties): A plant or chemical substance that alters human consciousness and has been subjected to rigorous forms of control (e.g., "war on drugs").

  • Legal Exclusions (UK Psychoactive Substance Act $2016$, Section $2$): Alcohol, tobacco or nicotine-based products, caffeine, food and drink, medicinal products, and drugs already regulated under the Misuse of Drugs Act $1971$.

Drug Classification and Nomenclature

  • Methods of Classification:     - By Source: Naturally occurring (e.g., Opium from poppy, Morphine from opium, cocaine from coca plant, Ephedrine from Ma huang); Semi-synthetics (e.g., Heroin from morphine, LSD from Ergot fungus); Synthetics/Designer drugs (e.g., Methadone, Amphetamine, Fentanyl, MDMA).     - By Chemical Structure: e.g., Phenethylamines, Benzenoids.     - By Mechanism of Action: e.g., Opioids.     - By Therapeutic Use: Analgesics, Anxiolytics, Anti-emetics.     - By Prototypical CNS/Behavioral Effect: Stimulants, Depressants, Hallucinogens, Psychotherapeutics.     - By Popular/Street Designation or Legal/Social Status.

  • Prototypical CNS Effects (Psychopharmacology, Box $1.3$):     - CNS Stimulants: Amphetamine, Cocaine, Nicotine.     - CNS Depressants: Barbiturates, Alcohol.     - Analgesics: Morphine, Codeine.     - Hallucinogens: Mescaline, LSD, Psilocybin.     - Psychotherapeutics: Prozac, Thorazine.

  • Naming Conventions Example:     - Generic: Amphetamine; Chemical: $(\pm)\text{-alpha-methylbenzene-ethylamine}$; Lab Designation: SKF?; Proprietary: Benzedrine®, Dexedrine®, Adderall®; Street: Uppers, Speed.     - Generic: Diazepam; Chemical: $7\text{-chloro-1-methyl-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one}$; Lab Designation: Ro-$42679$; Proprietary: Valium®; Street: Downer, Tranq.     - Generic: Lysergic Acid Diethylamide; Chemical: $(6aR,9R)\text{-N,N-diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo-[4,3-fg]-quinoline-9-carboxamide}$; Lab Designation: LSD-$25$; Proprietary: Delysid®; Street: Acid, tabs.

Sociolegal Frameworks and Harm

  • United States Drug Scheduling (DEA):     - Schedule I: Most abuse potential, no medicinal qualities (e.g., Heroin, LSD, Marijuana, Ecstasy).     - Schedule II: High abuse potential, some medicinal qualities (e.g., Cocaine, Meth, OxyContin, Adderall).     - Schedule III: Moderate abuse potential, acceptable medicinal qualities (e.g., Ketamine, Steroids).     - Schedule IV: Low abuse potential, acceptable medicinal qualities (e.g., Xanax, Valium).     - Schedule V: Lowest abuse potential (e.g., Robitussin AC).

  • United Kingdom Drug Control Instruments:     - Misuse of Drugs Act $1971$: Prevents misuse via bans on possession/supply unless licensed. Uses harm ratings based on Physical harm, Dependence, and Social harm.     - Human Medicines Regs $2012$.     - Psychoactive Substance Act $2016$.

  • UK Drug Classification and Penalties:     - Class A: Crack cocaine, heroin, ecstasy (MDMA), LSD, magic mushrooms. Possession: Up to $7$ years/fine; Supply: Up to life in prison.     - Class B: Amphetamines, cannabis, codeine, ketamine. Possession: Up to $5$ years/fine; Supply: Up to $14$ years.     - Class C: Anabolic steroids, benzodiazepines. Possession: Up to $2$ years/fine; Supply: Up to $14$ years.     - Temporary Class Drugs: Government can ban new drugs for $1\text{ year}$ (e.g., ethylphenidate derivatives).

  • Scientific Assessments of Harm (Nutt et al., 2010):     - Multi-criteria decision analysis ($16$ criteria including mortality, dependence, and economic cost).     - Alcohol was ranked the most harmful drug overall with a score of $72$, followed by Heroin ($55$) and Crack cocaine ($54$).     - Disparity exists between scientific harm ratings and legal classifications (e.g., Ecstasy and LSD ranked very low for harm but are Class A).

Drug Use, Abuse, and Addiction

  • Motivations for Drug Use:     - Experimentation/Novelty seeking.     - Pleasure (reward/desire).     - Self-Medication (relieving anxiety, depression, pain).     - Peer pressure.

  • Spectrum of Use: Drug taking does not always equal addiction. Categories include Experimental, Recreational/Casual, and Circumstantial use.

  • DSM-IV Criteria for Substance Abuse: Maladaptive pattern leading to impairment/distress manifested by $\geq 1$ criteria over $12\text{ months}$:     - Failure to fulfill role obligations.     - Use in physically hazardous situations (e.g., driving).     - Substance-related legal problems.     - Persistent social/interpersonal problems.

  • DSM-IV Criteria for Substance Dependence: Maladaptive pattern manifested by $\geq 3$ criteria within $12\text{ months}$:     - Tolerance: Need for increased amounts or diminished effect of same amount.     - Withdrawal: Characteristic syndrome or use to avoid symptoms (Note: neither necessary nor sufficient for addiction).     - Taken in larger amounts or longer periods than intended.     - Persistent desire/unsuccessful efforts to cut down.     - Significant time spent obtaining/using/recovering.     - Reduced social/occupational activities.     - Continued use despite knowledge of physical/psychological problems caused by it.

  • DSM-V Changes:     - Added a severity scale (mild, moderate, severe).     - Included non-drug addictive disorders (gambling).     - "Dependence" used only in a pharmacological sense.     - Removal of legal criteria.     - Added "Craving" to criteria.

  • Definitions of Addiction:     - WHO ($1981$): A syndrome where drug use is given much higher priority than behaviors that once had higher value; associated with compulsive behavior at extremes.     - J.H. Jaffe ($1990$): Exhibits characteristics of a "chronic relapsing disorder."