Drugs and Addiction

Module 4: Motivation

Chapter 9: Hunger, Eating, Health

Chapter 10: Hormones, Sex Behavior

Chapter Overview

  • A. Principles of Drug Action

    • Overview of how drugs function in the body.

    • Role of the circulatory system in drug distribution throughout the body.

    • Administration methods:

    • Oral

      • Common and convenient, but outcome varies based on digestion.

    • Injection

      • Various types include:

      • Intravenous: Fastest action.

      • Intramuscular: Slower absorption.

      • Subcutaneous: Slowest absorption.

    • Inhalation

      • Rapid absorption into the bloodstream due to large surface area in lungs.

    • Blood-Brain Barrier (BBB): A selective permeability barrier that protects the brain but limits drug passage, significant in the study of psychotropic medications.

    • Drug Action: Mechanisms by which drugs exert their effects on the body.

    • Drug Elimination:

    • Metabolism: Chemical alteration of drugs, primarily by the liver.

    • Excretion: Removal of drugs from the body, chiefly through urine.

    • Example: Alcohol

    • Commonly understood to illustrate principles of drug action and metabolism.

    • Drug Tolerance:

    • Definition: Diminished response to a drug after repeated use.

    • Types of tolerance:

      • Cross Tolerance: Tolerance to one drug leads to tolerance to another.

      • Metabolic Tolerance: Increased metabolic breakdown of a substance.

      • Behavioral Tolerance: Adaptation to the drug's effects within certain contexts.

    • Drug Withdrawal: Physical and psychological symptoms that occur after reduction or cessation of intake.

B. Commonly Used Drugs

  • Alcohol

    • Negative Effects: Impact on physical and mental health, including risk of addiction and dependence.

    • Classification: Depressant drug affecting the central nervous system.

    • Effects at Various Doses:

    • Low Doses: Mild euphoria, relaxation, and lowered inhibition.

    • Moderate Doses: Increased euphoria, decreased coordination, possible negative judgment.

    • High Doses: Severe impairment, risk of alcohol poisoning.

    • BAC Effects: Blood Alcohol Concentration (BAC) measures intoxication level; be familiar with thresholds corresponding to various levels of impairment.

    • Four Phases of Alcohol Withdrawal: Characteristic stages of symptoms (details not to be assessed on time durations).

    • Alcohol-Related Diseases: Health issues related to chronic alcohol use including liver disease, heart problems, etc.

  • Cannabis

    • Active Ingredients: Phytocannabinoids such as THC and CBD.

    • Stigma and Scheduling: Social perceptions and legal classifications affecting research and usage.

    • Effects at Various Doses:

    • Low Doses: Mild relaxation, altered perception, increased appetite.

    • High Doses: Enhanced psychological effects, risk of anxiety, or paranoia.

    • Dependence and Health Hazards: Potential for misuse and physical health consequences.

    • Therapeutic Uses: Usage in alleviating chronic pain, nausea, and other medical conditions.

  • Psychostimulants

    • Drugs in this Category: Substances that elevate mood, increase feelings of well-being, and increase energy.

    • Coca Plant: Source of cocaine, known for its stimulant properties.

    • Khat Plant: Contains cathinone, a stimulant with effects similar to amphetamines.

  • Opioids

    • Differentiation between Opioids (synthetic derivatives) vs. Opium (natural substance).

    • Three Factors Promoting Use: Biological, psychological, and social influences that lead to opioid consumption.

    • Heroin: A form of opioid that is associated with high rates of addiction and overdose.

    • Opioid Epidemic: A significant public health crisis characterized by high rates of opioid prescription and abuse, and its consequences.

    • Three Phases and Their Causes: Development of opioid misuse, including initial prescription practices, increased availability, and social factors.

    • Cause of Most Recent Decline: Recent changes in prescribing practices and increased attention to addiction treatment and awareness.

    • Prevalence of Drug Use: Statistics and social trends surrounding drug abuse in various populations.

C. Understanding Addiction

  • Definition: A chronic, relapsing disorder characterized by compulsive drug seeking, continued use despite harmful consequences, and long-lasting changes in the brain.

  • Role of Addiction:

    • Preoccupation: Persistent focus on obtaining and using the drug.

    • Withdrawal/Negative Affect: Emotional and physical distress experienced during abstinence, often leading to relapse.

    • Binge Intoxication: Periods of heavy drug use followed by binge within an episodic pattern.

  • Move from Impulsive to Compulsive Drug Use: Transition from voluntary drug use decisions to uncontrollable urges that define addiction behavior.