Substance Abuse and Addiction Flashcards
Why might people take recreational drugs?
Reduce anxiety Rebel Get high Escapism Everyone does Curiosity To fit in Why not? Stay awake
What is a drug?
What is drug abuse?
Drug = any medication or compound that gets into the body and has an effect
It is about the habitual use, not the drug itself - can be legal or illegal drugs
Why might people take recreational drugs?
Reduce anxiety Rebel Get high Escapism Everyone does Curious to fit in Why not? Stay awake
What reasons for taking drugs are positively reinforced and what reasons are negatively reinforced?
Gain positive state (positive reinforcement) = Rebel Get high Escapism Like it Stay awake (i.e caffeine)
Overcome adverse state (negative reinforcement) = Boredom To get to sleep Reduce anxiety Feel better
What reasons for taking drugs are positively reinforced and what reasons are negatively reinforced?
Gain positive state (positive reinforcement) = Rebel Get high Escapism Like it Stay awake (i.e caffeine)
Overcome adverse state (negative reinforcement) = Boredom To get to sleep Reduce anxiety Feel better
What is the course of alcohol/drug use, harmful use, and/or addiction?
I like - experimental / recreational use. causes no/limited difficulties
I want - increasingly regular use
I need - spiraling, dependence
When does substance use become harmful?
Actual damage to their physical or mental health
What are the ICD-10 diagnostic criteria for dependence syndrome?
Strong desire to take the substance
Difficulties in controlling onset, termination or levels of use
Physiological withdrawal state
Evidence of tolerance: need to take more to get same effect
What are the ICD-10 diagnostic criteria for dependence syndrome?
Strong desire to take the substance
Difficulties in controlling onset, termination or levels of use
Physiological withdrawal state
Evidence of tolerance: need to take more to get same effect
What is dependence?
Refers to physical adaptation to a substance - brain/body chemistry adapts to the constant presence of the drug = tolerant and dependent
Can be dependent not addicted - as there are no other beahviours e.g. there is no drug seeking behaviour, avoiding commitments, etc.
e.g. opiod
What are some examples of other behavioural addictions?
Gambling disorder
Internet gambling disorder
These are no longer classified as impulse control disorders
How are drugs made more addictive?
Speeding up brain entry - gives a greater ‘rush’
What are some issues with a health coaching / MI perspective?
You assume the patient’s resourcefulness
The relationship must have mutual trust and respect
Coaching is about change and action, but a patient may not want to explore the issue and move forward
What is the pathway from use to addiction?
Pre-existing vulnerability:
Family history
Age
Drug exposure:
Tolerance - compensatory neuroadaptations to maintain brain function
Resilience
Recovery:
Sustained recovery is achievable
Most go into cycles of remission and relapse
What is the pathway from use to addiction?
Pre-existing vulnerability:
Family history
Age
Drug exposure:
Tolerance - compensatory neuroadaptations to maintain brain function
Resilience
Recovery:
Sustained recovery is achievable
Most go into cycles of remission and relapse
How can alcohol addiction lead to tolerance and withdrawal?
Drinking often / constantly = alters brain chemistry and increases tolerance (by resetting the baseline)
This leads to withdrawal symptoms without the alcohol due to reset baseline
How can alcohol addiction lead to tolerance and withdrawal?
Drinking often / constantly = alters brain chemistry and increases tolerance (by resetting the baseline)
This leads to withdrawal symptoms without the alcohol due to reset baseline
What does alcohol do?
Alters the balance between brain’s inhibitory and excitatory system
What does chronic alcohol exposure result in?
Tolerance:
Neurodaptations so GABA and glutamate remain in balance in presence of alcohol
Upregulation of excitatory system
Reduced function in inhibitory system - tolerance
GABA-A receptors: alcohol causes the receptor to switch in subunits that are less sensitive to alcohol
What happens after chronic alcohol exposure when alcohol is no longer present?
Withdrawal:
GABA and glutamate are no longer in balance - withdrawal state
Reduced function in inhibitory system - GABA-A receptor (downregulation)
Upregulation of excitatory system - NMDA receptor:
leads to increase in Ca2+ entering the cell, causing more calcium channels to open
this toxicity leads to hyper excitability (seizure) and cell death (atrophy)
What happens after chronic alcohol exposure when alcohol is no longer present?
Withdrawal:
GABA and glutamate are no longer in balance - withdrawal state
Reduced function in inhibitory system (downregulation)
Upregulation of excitatory system - NMDA receptor:
leads to increase in Ca2+ entering the cell, causing more calcium channels to open
this toxicity leads to hyper excitability (seizure) and cell death (atrophy)
What are the models of addiction?
Rewards deficiency
Overcoming adverse state
Impulsivity/Compulsivity
What is the dopamine pathway?
How does it feed into addiction?
Also known as the pleasure-reward-motivation system
Natural rewards e.g. food, sex - increase dopamine levels in the ventral striatum = feelings of pleasure / reward
Drug abuse has the same effect
Addiction = shift from pleasure state to motivation state with regular use of the drug = ‘reward deficient’ state
How can drugs of abuse modulate dopamine?
Drugs block dopamine reuptake e.g. cocaine, amphetamines
Leads to increased conc. in the synapse = direct effect
Amphetamine enhances release of dopamine
Or other drugs e.g. alcohol, opiates, nicotine increase dopamine neuron firing = indirect effect
How can you assess function in the reward pathway?
fMRI
Monetary incentive delay task - anticipation of winning money
Ventral striatum lights up
What effects of the drug contribute greatest to the motivation of abusing drugs?
Negative reinforcement
Overtime, as the tolerance builds, lower high
But without the drug, negative affects of the withdrawal increases motivation to take the drug
What are targets for treatment?
What is the target in the reward system?
What is the target in the stress system?
Brain regions associated with withdrawal and negative emotional states in addiction
Reduced dopamine and mu opioid function
Increased activity in many including kappa opioid (dynorphin), noradrenaline (arousal system), CRF (stress) etc.
What is seen on fMRI in abstinent drug addicts’ withdrawal?
Heightened brain response in left amygdala in abstinent polydrug addicts to aversive images
What does a change from voluntary drug use to more habitual and compulsive use involve?
Prefrontal to striatal control over drug taking
Ventral (limbic or emotional) to dorsal (habit) striatum
How is the neurocircuitry system tested in inhibitory control?
Use fMRIs
Go-nogo task - series of symbols, press button when the symbol next to it differs, don’t press button if the symbol next to it is the same
Look at the dorsal striatum and inferior frontal gyrus
When are benzodiazepines used?
When is acamprosate used?
To treat alcohol withdrawal
To support abstinence, neuroprotection in alcoholism
When is naltrexone used?
Opioid antagonist
Block heroin use in opioid addicts and to modulate reward system in alcoholism
