Substance Use and Addictions Flashcards
Positive reinforcement?
Gain positive state:
-stay awake
-get high
-enjoy it
-escapism
Negative reinforcement?
Overcome adverse state:
-boredom
-reduce anxiety
-to get to sleep
-feel better
Course of addiction?
Like -> Want -> Need
Dependence syndrome ICD-10?
3 or more of following
1. Strong DESIRE or sense of compulsion to take substance
2. DIFFICULTIES CONTROLLING substance taking behaviour (onset, termination, levels)
3. Physiological WITHDRAWAL state when stopped or reduced
4. TOLERANCE
5. Progressive NEGLECT of alternative interests
6. PERSISTING with use despite evidence of harmful consequences
Addiction?
Continue using despite being harmful
Cannot stop using drug
Neglect of work, social, or family obligations
Tolerance and withdrawal
Dependence?
Body physically adapted to drug
-tolerance/withdrawal
can be dependent and not addicted
Behaviour addictions?
-gambling disorder
-internet gaming disorder
3 levels of addiction?
- Hazardous use (high quantity and frequency)
- Harmful use (consequences - physical, social, psychological)
- Dependence/addiction (tolerance, withdrawal)
Elements involved in alcohol/drug use and addiction?
-social, environmental factors
-drug factors (faster entry=more addictive)
-personal factors (genetic, personality)
Models of addiction?
-reward deficiency (positive reinforcement)
-overcoming adverse state (withdrawal, anxiety - negative reinforcement)
-impulsivity/compulsivity
Alcohol acute effects?
Blocks excitatory system (through NMDA receptor) - impaired memory, alcoholic blackouts
Boosts inhibitory system (through GABA-A receptor) - anxiolysis, sedation
Chronic alcohol exposure neuroadaptations?
Upregulation of excitatory system
Reduced function of inhibitory system (tolerance)
Upregulation of excitatory system from chronic alcohol?
Increased number of NMDA receptors - increase in calcium release which is toxic
calcium is toxic leading to hyper excitability (seizures) and cell death (atrophy)
Reduced function of inhibitory system from chronic alcohol?
GABA-A receptor - switch in subunits to make less sensitive to alcohol
TOLERANCE
To boost GABA function?
Treat with benzodiazepines
Ventral striatum
Natural rewards increase levels of dopamine in ventral striatum
Dopamine pathway?
Pleasure-reward-motivation system
Cocaine and amphetamine interaction with dopamine?
Block dopamine reuptake
amphetamines enhance release of dopamine
Alcohol and nicotine effect on dopamine?
Increase dopamine neurone firing in VTA (ventral tegmental area)
Reward system in abstinent addicts?
Blunted activation of reward system in abstinent addicts compared with controls
blunted response = more likely relapse (reward deficiency)
Amygdala?
Emotional processing
Involved dysregulation of stress system, increase in kappa/dynorphin opioid system, noradrenergic activity
Positive -> negative reinforcement?
As addiction/dependence develops
Ventral -> dorsal migration
Fronto-striatal connections with reduced frontal ‘control’ or striatal activity
Move from ventral (limbic) to dorsal (habit) striatum as dependence develops
Intoxication?
Transient, temporary state that disappears when drug is eliminated
Withdrawal?
Signs + symptoms when dose is reduced or stopped
Tolerance?
Drug produces decreased effect after repeated use
Harmful use? ICD-10
-pattern of substance that causes damage to health
-physical or mental damage
-adverse social consequences
-harmful use including bingeing (doesn’t include hangover alone)
-does not fulfil any other diagnosis within substance use (e.g dependence)
cannot be harmful use and dependence
ICD-11 similarities? (Dependence and harmful use)
Distinction between dependence and harmful use is preserved
ICD-11 differences (harmful use)?
Single episodes of harmful use differentiated from pattern of harmful use
harmful use now also include harm to health of others
ICD-11 differences (dependence)?
former 6 criteria bundled into 3 pairs - 1 criteria sufficient
1. IMPAIRED CONTROL over substance use
2. INCREASING PRECEDENCE of substance over other aspects of life
3. NEUROADAPTATION to substance
usually over 12 months but diagnosis can be made after 3 months continuous
DSM-5 classification differences? Addiction
Remained opioid use disorder and alcohol use disorder
Single continuum of mild, moderate, severe
No longer uses terms abuse or dependence
Alcohol excretion rate?
1 unit per hour
Recommended intake units?
14 per week for men and women
Spread over 3 or more days
CAGE?
Cut down
Angry
Guilty
Eye opener
Absorption pharmacology alcohol?
60 mins for maximum blood concentration
Alcohol pharmacodynamics?
Enhances neurotransmission at GABA-A receptors (causing anxiolysis)
Inhibits NMDA mediated glutamate release (amnesic)
Alcohol metabolism?
Ethanol oxidised by alcohol dehydrogenase to acetaldehyde
Acetaldehyde dehydrogenase turns acetaldehyde to CO2 and water
Alcohol assessment? Physical examination
Examination - jaundice, bruising, clubbing, oedema, ascites, spider naevi
Wernicke’s encephalopathy triad?
Ataxia
Confusion
Opthalmoplegia
Alcohol withdrawal stages?
6-12 hours - minor withdrawal symptoms (tremulousness, anxiety, nausea…)
12-24 - alcoholic hallucinosis (usually accusatory or derogatory voices)
12-48 - withdrawal seizures
48-72 - delirium tremens
Delirium tremens?
Medical emergency
Hallucinations, confusion and disorientation, hypertension, agitation, tachycardia, fever, severe tremor
Alcohol withdrawal management?
Benzodiazepines
Opioid effects?
- Relieve pain - analgesic
- Euphoria
endogenous (endorphins) regulate pain and mood
Opioid receptors?
Mu, delta, kappa - affected by heroin, codeine
Opioid assessment examination?
Collapsed veins, track marks
endocarditis
Hep. B, HIV
Pneumonia
Opioid withdrawal scale?
COWS
Clinical opiate withdrawal scale
Opiate overdose treatment?
Naloxone
Opiate overdose signs?
Not moving, can’t be woken, slow or no breathing
Choking or gurgling sounds, snoring
Tiny pupils
Clammy or cold skin
Blue nails
Opioid addiction symptoms?
Tachycardia, snotty, achy, worry
All diagnostic criteria similar features?
-loss of control
-functional impairment
-neuroadaptation
Addiction history taking?
Triggers, method, withdrawal, previous treatment
Willing to change?
Alcohol assessment? Neurological
Neurological - Wernicke’s encephalopathy, Korsakoff’s syndrome
Alcohol abstinence drug and effect?
Acamprosate - increases GABA, NMDA antagonist
Detox drug?
Benzodiazepines
Chlordiazepine
Thiamine, folate
