Drugs and Behaviour Final Flashcards
(80 cards)
Production of Alcohol
Fermentation: Yeast + sugar (grapes or grains) → Alcohol.
Distillation: Heating fermented liquid → Capturing vapor → Higher alcohol concentration (e.g., spirits).
History of Alcohol-Ancient Use
Evidence of alcohol use 9,000 years ago (China); Greeks, Egyptians, and English known for beer, wine, mead.
History of Alcohol-North America
Early drinking culture, Prohibition (14 years), then fluctuating consumption.
Measuring Alcohol Levels and Tools
Blood Alcohol Concentration (BAC):
mg alcohol/100 ml blood or percentage (e.g., 0.08% = 80 mg/100 ml).
SI Unit: mmol/L (e.g., 80 mg/100 ml = 17.4 mM).
Measurement Tools: Breathalyzer (BrAC), blood tests.
Pharmacokinetics of Alcohol
Absorption: Mostly in small intestine (slower with food).
Distribution: Alcohol is water-soluble (affects body composition impact — more fat → higher BAC).
Metabolism:
Liver processes 90–98% of alcohol: Ethanol → Acetaldehyde → Acetate.
Kinetics: Originally thought to be zero-order (constant rate), now understood to be dose-dependent first-order kinetics.
Rate of metabolism depends on: Drinking experience, sex, genetics, age, food intake.
Neurotransmitter Affected By Alcohol
GABA: Enhances inhibition → Relaxation, sedation.
Glutamate: Suppresses excitation → Cognitive impairment.
Dopamine: Increases reward → Euphoria, craving.
Opioids: Enhances pleasure and reinforcement.
Long-Term Changes of Alcohol
Chronic alcohol use increases glutamate sensitivity and reduces dopamine receptors, contributing to tolerance and dependence.
Positive and Negative Effects of Alcohol
Positive Effects: Mood improvement, stress relief (at low doses).
Negative Effects: Disinhibition, memory impairment, reduced motor coordination, slower reaction times, poor decision-making.
Stages of Intoxication
Initial Euphoria: Talkativeness, excitement.
Increasing BAC: Poor cognition, sensory dulling.
High BAC: Blackouts, stupor, nausea, alcohol poisoning.
Lethal Risk: Respiratory failure (e.g., Amy Winehouse case).
Short Term Health Impacts of Alcohol
Accidents, alcohol poisoning, impaired driving.
Long Term Health Impacts of Alcohol
Liver Damage: Fatty liver → Cirrhosis (50% of alcohol-related deaths).
Nervous System Disorders: Korsakoff’s syndrome, epilepsy, dementia.
Cancer: Alcohol is genotoxic (e.g., linked to breast cancer).
Reproductive Health: Impotence (males), menstrual disruption (females).
Fetal Alcohol Spectrum Disorder (FASD): Severe developmental issues.
Alcoholism as a Disease
DSM-5 Diagnosis: Alcohol Use Disorder (AUD).
Genetic Factors: ADH/ALDH enzyme variations.
Tolerance: Metabolic, pharmacodynamic, behavioral.
Withdrawal: Minor (early) to severe (late-stage) symptoms.
Types of Alcoholism
Type I: Late onset, environmental stressors, psychological risk.
Type II: Early onset, high genetic risk, impulsivity.
Treatment of Alcoholism
Behavioral Therapy: Support groups (e.g., Alcoholics Anonymous).
Medications:
Acamprosate: Reduces cravings.
Disulfiram: Induces unpleasant effects when drinking.
Naltrexone: Reduces the pleasurable effects of alcohol.
Natural Opioids
Derived from the opium poppy (limited production window of ~10 days per year).
Morphine: Most abundant, used in pain management.
Codeine: Isolated in 1821, now derived from morphine.
Thebaine: Used to synthesize oxycodone and other opioids.
Hydrocodone: Most commonly prescribed opioid in the U.S.
Synthetic & Semi-Synthetic Opioidsc
Heroin: Semisynthetic derivative of morphine.
Meperidine & Fentanyl: Fully synthetic, potent opioid receptor stimulants (fentanyl is 30–50x more potent than heroin).
Designer Drugs: MPPP, China white, and krokodil have serious side effects.
History of Opium Use
Used since ancient Sumerians (called the “joy plant”).
Spread from the Mediterranean to the Middle East, Africa, and Asia.
1600s: Widespread addiction in Britain, leading to the 1868 Pharmacy Act.
U.S.: Morphine was the dominant opioid; heroin was invented in 1898 by Heinrich Dreser for Bayer and marketed as a non-addictive pain reliever. Banned in the U.S. in 1924.
Routes of Administration for Opiods
Oral: Common for prescription opioids but less effective.
Inhalation: “Chasing the dragon” (heroin use).
Injection: Rapid onset, high abuse potential.
Transdermal & Nasal: Used for medical and recreational purposes.
Pharmacokinetics of Opioids
Absorption & Distribution:
Readily cross the Blood-Brain Barrier (BBB), except morphine (low lipid solubility).
Concentrate in the brain, lungs, kidneys, and liver.
Metabolism & Elimination:
Liver metabolism: Two phases involving cytochrome P450 enzymes.
Genetic differences and substances (e.g., St. John’s wort) can affect metabolism.
Pharmacodynamics of Opioids
Opioid receptors (identified in the 1970s) are activated by endogenous neuropeptides (endorphins, enkephalins, dynorphins).
Classical receptors: Mu (µ), Kappa (κ), Delta (δ).
Non-classical: Opioid receptor-like 1 (ORL-1).
Opioid receptor agonists inhibit neuron activity via G-protein-coupled mechanisms.
Opioid Receptor Action
Pure Agonists: Fully activate µ receptors (e.g., morphine, fentanyl).
Partial Agonists: Partially activate µ receptors (e.g., buprenorphine).
Pure Antagonists: Block µ receptors (e.g., naloxone, naltrexone).
Mixed Agonist-Antagonists: Act as agonists on some receptors while blocking others (e.g., pentazocine).
Principal Effects of Opioids
Analgesia (Pain Relief):
Reduce nociceptor excitability.
Bind to µ, δ, and κ receptors in pain-transmitting regions.
Reward System & Addiction:
Opioids increase dopamine release in the brain’s reward pathways.
Dynorphin activation may counteract reward, increasing κ-receptor binding.
Opioids Effects on Animals
Self-administration: Animals readily self-administer opioids.
Discriminative Stimulus Properties: Rats differentiate opioids quickly; tolerance develops in 1–3 days.
Conditioned Place Preference (CPP): Rats prefer locations where they received heroin, demonstrating its reinforcing effects.
Opioids Effects on Humans
Euphoria: Common in experienced users.
Cognitive & Performance Effects: Sedation, low attention, impaired memory.
Mood Changes: Positive moods followed by negative ones.
Abuse Liability: Opioids have high addiction potential.
