Table of Contents. PSY3190: Addiction Studies

Transcription

1 Table of Contents Defining Addiction... 8 What is a drug?... 8 Harms Associated with Psychoactive Drugs... 8 Key DSM Definitions... 8 Key ICD-10 Definitions... 9 Classifications of Psychoactive Drugs... 9 Drug Policy What is Drug Policy? Policy Levers Challenges of Drug Policy Types of Policy Approaches War on Drugs vs. Harm Minimisation The National Drug Strategy: Australia s Current Approach The Policy Cycle Why Study Pharmacology? Assisting Knowledge Factors Affect Drug Absorption Psychopharmacology Overview Pharmacokinetics vs. Pharmacodynamics Pharmacokinetics Processes Modes of Administration Absorption Distribution Metabolism Excretion Pharmacodynamics Elements Drug Interaction Agonist v Antagonist Reinforcement

2 Tolerance Drug Dependence Withdrawal Drug Interactions Antagonism Evolution of Reinforcement & Drugs What is reinforcement? Evolutionary Purposes of Reinforcement...24 Brain Structures & Neural Pathways of Reward Beginnings of Structure...24 The Brain s Pleasure Centre : Mesolimbic Dopamine Pathway Structures and Neurotransmitters Together The Role of Endorphins Maladaptive Changes in Drug Circuitry Neurotransmitter Defects Hijacking Reward Circuity Biological Basis of Addiction Biological Theories of Drug Addiction Incentive Desensitisation Genetic Theories Neurocognitive Studies Decision Making Studies Addiction: A Developmental Disorder? Psychological Aspects in Current Systems...39 Symptoms of Abuse and Dependence The Role of Adolescence Developmental Model of Addiction Main Theories of Behavioural Change (Readings) Behavioural Theories of Addiction Overview Conditioning Theories Cognitive Theories of Addiction Overview

3 Cognitions Relating to Substance Use Cognitive Model of Substance Abuse (Beck) Social Cognitive Theory (Bandura) Personality Theories of Addiction Overview Two Dimensions Integrative Model I: Transition from impulsivity to compulsivity Impulsivity Compulsivity (Animal Models) Transition from Impulsivity Compulsivity (Human Models) Neuropsychology: Assessment of behavioural consequences of brain systems dysfunction Perseveration-Compulsivity: Probabilistic Reversal Transition Vulnerability to Dependence Integrative Model II: Emotion, Interoception and Decision-Making Somatic Marker Model Interoceptive Awareness Understanding Addiction and Consequences General View Defining Addiction in Social Contexts Overview of Theories of Drug Use and Addiction Liberal Models Disease Models Self-Medication Hypothesis Historical Views of Addiction Social Theories...59 Social Drivers of Addiction Hovarth: Social Learning Theory of Addiction Zinberg s Theory of Drug Addiction (Drug, Set, Setting) Drug Using Identities Parker: Culture and Normalisation Stigmatisation v. Normalisation Case Study: Is Addiction A Brain Disease? Neuroscience Evidence for the Brain Disease Model Limitations of Neuroscience Evidence

4 Social Science Evidence for the Brain Disease Model Policy and the Brain Disease Model Industry the Brain Disease Model Direct Treatment of the Addicted Brain Ablative Neurosurgery (Eg. For Heroin Addiction) Deep Brain Stimulation Medicalisation of Addiction Impact of Brain Disease Explanations on Treatment Views of Addicted Individuals Neurobiology and Policy Summary of Social Theories Epidemiology Forms of Problem Gambling DSM V and Problem Gambling Current Integrative Models of Problem Gambling Biopsychosocial Model Pathways Model Issues with Existing Models Heterogeneity of Gambling Forms Individual Differences in Problem Gambling Genetics/Heritability Personality Reward/Punishment Cognitive Variables Risk Factors for Maintenance of Problem Gambling Brain Functioning Neurobiological Models of Problem Gambling & Addiction Stress Model of Addiction Ventral to Dorsal Shift I-RISA Model Neuroscience Evidence Brain Activity After Winning v. Losing Diminished Sensitivity to Losses

5 Cue Reactivity in Problem Gambling Interpreting Gambling Brain Research Key Themes: Neuroscience Findings Neuroscience Based Treatment? Policy to Reduce Gambling Conflicts of Interest Policy and Neuroscience Evidence-Based Policy Decisions Problem Gambling Summary Vulnerable Populations...93 Women...93 Why separate women? Issues Women Face Hidden Drug Use Women and the Actions of Alcohol Women and Illicit Drug Use Pregnancy Marital Status Children Access to Treatment Violence Prostitution Health Risks for Women Menstrual Irregularities Pregnancy and Breastfeeding Issues Suicide and Mental Health Elderly People Prevalence Tobacco Alcohol Prescribed Medications Illicit Drug Use

6 Assessment Treatment Smoking Treatment Alcohol Benzodiazepines Aboriginal and Torres Strait Islanders Patterns of Use Alcohol Usage Illicit Drug Usage Patterns Injecting Drug Usage Pattern Inhalant Usage Patterns Issues for ATSIs Unemployment Education Social and Emotional Wellbeing Harms Theoretical Perspectives on Use Historical Perspective Anthropological Perspective Physiological Perspective Psychosocial Perspective Interventions Components of Effective Treatment Community Approaches Theories of Aetiology of Coexisting Disorders Key Principles of Treatment Biological Influences on Risk of Addiction Genes Maturational Stages Neurodevelopmental disorders (e.g. ADHD) Psychological Influences on Risk of Addiction Emotion Recognition Social Cognition Deficits

7 Personality Disorder Types Reappraisal Tasks: Emotion Regulation Difficulties in Addiction Social Influences on Risk of Addiction Prevention in Adolescents Principles of Effective Prevention in Adolescents Early Intervention Hotspots Harm Reduction

8 Week One: Defining Addiction & Drug Policy Defining Addiction What is a drug? WHO: A drug is a chemical entity used non-medically, self-administered for its psychoactive effect. Other definitions may include: Any substance that alters our physiology, mood, cognition or behaviour but does not constitute food or nutrient. Any substance taken with the intent to alter mood, cognition or behaviour. Psychoactive substances are drugs that have cognitive and/or behavioural effects. Harms Associated with Psychoactive Drugs Toxicity (Intoxication) Usually an immediate effect of the drug, when the blood level concentration rises rapidly. Alcohol is high toxicity. Cannabis is generally low in toxicity, but depending on the route of administration (eating vs. smoking), it may exit faster into the bloodstream and therefore, by definition, more intoxicating. Dependence A delayed effect and potentially long-lasting. Addiction potential. Seen in heroin, methamphetamines, nicotine. Key DSM Definitions Substance Abuse: self-administration of psychoactive substance. Substance-Related Disorders: usage pattern that meets DSM criteria (allow for subtyping based on a continuum from mild to severe. Withdrawal: negative reactions generated by body/brain in absence of the substance: psychological and physiological issues (eg. Insomnia, anger) Tolerance Feel the effects less, may started using higher doses. Significant time spent in activities to obtain/use, interfere with normal activities 8

9 Craving: arousal, desire, conflict from strong desire to use the substance. Key ICD-10 Definitions Associated with harmful use, not abuse. Need to have three or more of the following during the past year: A strong desire or sense of compulsion to take the substance Difficulties in controlling substance-taking behaviour in terms of its onset, termination, or levels of use A physiological withdrawal state when substance use has ceased or has been reduced, evident from: The characteristic withdrawal syndrome for the substance; or use of the same (or closely related) substance with the intention of relieving or avoiding withdrawal symptoms Evidence of tolerance, such that increased doses of the psychoactive substance are required in order to achieve effects originally produced by lower doses Progressive neglect of alternative pleasures or interests because of psychoactive substance use, increases in the amount of time necessary to obtain or take the substance or to recover from its effects Persisting with substance use despite clear evidence of overtly harmful consequences, such as harm to the liver through excessive drinking, depressive mood states consequent to periods of heavy substance use, or drug-related impairment of cognitive functioning Classifications of Psychoactive Drugs Generally split into three categories. Depressants: Suppress, inhibit or reduce CNS activity Stimulants: Increase activity in the CNS Hallucinogens: Alter perceptions, thinking, feeling, sense of time and place Note, Narcotics: Sleep-inducing substances 9

10 Drug Policy What is Drug Policy? Refers to the intentions and actions of governments in relation to the control of drug addiction. Dynamic concept: as much about process as outcomes. Can involve: Programs to prevent the uptake of drugs Health and social service programs to assist users and minimise their consequences Laws and regulations to control supply. Involves all levels of government: Federal: Overarching agenda-setting and documenting the strategic intent for implementation through agencies State: Mostly implement drug policies Underpinned By harm minimization. Seeks balance between supply reduction, demand reduction and harm reduction. Policy Levers Government responses to drug use and related harms. May be through: Policy through advocacy: educating/persuading Policy through network: leveraging relationships within and across governments and partners. Policy through money: using spending and taxing powers Policy through direct government action: delivering services through public agencies Policy through law: legislation, regulation and official authority Challenges of Drug Policy Conflicting goals (eg. Ambulance v. police intervention) Coordination and communication across government portfolios (eg. Police and health) Balance (most appropriate mix of policy options) Politics Types of Policy Approaches From zero tolerance to harm reduction. Multifaceted approach: mix of policy interventions. 10

11 Policy Option Features Examples Make drug use Prohibition Era criminal. o Results in illegal Allocation of importation, unknown resources. content/purity of Medical Total Prohibition substances and a black response is the market thriving on prevention of exorbitant prices. additional Overall, not cost effective health complications. Possession of small quantities not prosecuted. Production and distribution of large quantities is prohibited. Different treatment of substances Partial Prohibition (classes) and amounts of those substances. Costineffectiveness impact of prohibition is acknowledged. Decriminalisation Removes criminal component of drug use. Remove or modify penalties. Change in enforcement of penalties. Netherlands Australia: possession of small amounts of cannabis subjected to fine (SA, ACT, NT, WA, VIC) Controlled Availability Substances are available in known doses nd purity. Heroin prescription programs in UK, Switzerland and Spain. Switzerland: o Established a needlepark 11

12 Policy Option Features Examples These o Established heroin trials in substances are 1994 with methadone, regulated. showed improve psychological and physical functioning, OD rate halved. Controlled Availability Uncontrolled Availability Aims: To provide information nd education to drug users. Profit taken out of the black market. Provision of substances is taxed which pays of the system and reduces law enforcement costs. Lifting all controls on illicit drugs. Not implemented anywhere in the world; not supported by most drug law reform advocates who support control on marketing, production and distribution. Unlikely to ever gain widespread community support. Netherlands: o Prescription heroin trials were very successful... o Methadone alone showed 32% improvement, but deterioration was seen across all areas of functioning after 2 months Uruguay o The Uruguayan Congress has voted to legalise marijuana. o This makes Uruguay the first country in the world where it s legal to grow, sell and consume the drug. o Those in favour of legalizing marijuana will reduce the power of the drug cartels but those against warn the country will be in complete contravention to provisions of International Drug Treaties they are party to War on Drugs vs. Harm Minimisation War on Drugs (history of U.S. policy) vs. Harm Minimisation (History of AU Policy) 12

13 Drugs in US a major issue, a war on drugs was proposed by Nixon in response to a high rate of heroin use in Vietnam. Policy 0f prohibition Whereas in the harm minimisation approach: Acknowledge drug use has always existed and will continue to exist Completely eradicating drug use is impossible Continued focus on eradicating drug problems may result in more harm for society Overall, harm minimisation aims to decrease the harm associated with drug use, rather than preventing drug use altogether Harm Minimisation and the Law Enforcement Traditionally law enforcement has taken a supply reduction approach Law enforcement can also contribute to demand reduction and harm reduction by: Improving links between police & treatment services Introducing cautioning & diversion schemes Changing legal status of drug or policing attitudes & behaviour (e.g. cannabis) Supporting other harm reduction strategies (e.g. needle exchange) The National Drug Strategy: Australia s Current Approach Objectives Minimise the level of illness, disease, injury and premature death associated with the use of alcohol, tobacco, pharmaceutical and illicit drugs; Minimise the level and impact of criminal drug offences and other drug-related crime, violence and antisocial behaviour within the community; Minimise the level of personal and social disruption, loss of quality of life, loss of productivity and other economic costs associated with the inappropriate use of alcohol and other drugs; and Prevent the spread of hepatitis, HIV/AIDS and other infectious diseases associated with the unsafe injection of illicit drugs. Outcomes? Assessment of the National Drug Strategy 2001 International attention and acclaim Recognises the complexity of drug use issues Shared decision making Promotion of partnerships A balanced approach Sound research infrastructure Recommendations have been followed up 13