Psychiatry SC076: I Cannot Help Myself, Taking These Pills Just Feels Good: Substance Abuse And Addiction Flashcards
Addiction
- Attachment to (Psychological) / Dependence upon (Psychological / Physiological)
- On any substance, thing, person, idea
- So single-minded + intense that virtually all other realities are ignored / given second place and consequences (even lethal ones) are disregarded
Terminology:
1. Problem use / Misuse
- Use for pleasure but with ***disregard for personal / social dangers
- Craving
- Strong + Irresistible ***desire
- Not necessarily pleasurable - Dependence (Physical / Psychological)
- Physical adaptation —> **Physical withdrawal symptoms
- **Psychological withdrawal symptoms - Addiction
- ***Extreme end of dependent spectrum
- Social + Personal decline, tolerance, withdrawal symptoms
Dependence syndrome ICD-10 criteria
- 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 been reduced
- Evidence of ***tolerance
- Progressive neglect of alternative pleasures or interests
- ***Persisting with substance use despite clear evidence of overtly harmful consequences
Substances being abused
- Alcohol
- Opioids (e.g. ***heroin, morphine, codeine, methadone)
- ***Cocaine (e.g. cocaine, crack)
- ***Amphetamines
- Sedative, hypnotics, anxiolytics
- Hallucinogens (e.g. LSD, ecstasy)
- Phencyclidine (e.g. PCP, ketamine)
- Inhalants
- ***Cannabis
- Nicotine
- Caffeine
Biological basis of addiction
Start off with Occasional use —> Addicted / Become habit
Occasional use:
- ***Impulsive act
—> Increase sense of arousal + sense of tension before the act (i.e. Positive reinforcement)
Addicted / Become habit:
- ***Compulsive act
—> Anxiety / Stress before + Relief after the act (i.e. Negative reinforcement)
Principles of reinforcement:
- Reinforcer: increase likelihood of a behaviour that precedes its presentation
- Positive reinforcement: Positive outcomes follows the behaviour (e.g. award)
- Negative reinforcement: Behaviour supported by avoidance / termination of aversive events (e.g. punishment)
***Stage of addiction
Binge intoxication (↑ reward circuits: VTA, NA) (**Impulsive stage)
—> Drug reinforcement + Further intoxication (↑ reward circuits: VTA, NA)
—> Withdrawal + Tolerance (↓ reward circuits: Anterior cingulate, Prefrontal cortex, Amygdala, changes in synapse / synaptic receptor —> downregulation of D2 receptors)
—> Craving / Preoccupation / Relapse (Amygdala for **conditional response, Hippocampus for **memory, Prefrontal cortex, Orbitofrontal cortex for **executive function) (Act is no longer pleasurable —> ***Compulsive stage)
—> Binge intoxication
Neurotransmitter in Addiction
Primary neurotransmitter:
1. Glutamate (Stimulatory)
2. GABA (Inhibitory)
—> Action, Sensation, Learning, Memory
Secondary neurotransmitter:
1. Dopamine
2. Noradrenaline
3. Serotonin
4. Acetylcholine
5. Endogenous opiate
6. Endogenous cannabinoid
Endogenous “addictive” neurotransmitter:
- Opioid peptides (e.g. Endorphins)
- Endogenous cannabinoids (e.g. Anandamide)
—> suggest a lot of pleasurable activities (e.g. eating, exercise) are involved in a reward system
All drugs have interaction with neurotransmitter:
- Mimic natural transmitter
- Release transmitter
- Block transmitter
Dopaminergic system
- Cognition
- Schizophrenia
- Parkinson’s disease
- Attention deficit - Motor
- Parkinson’s disease - Reward learning
- Drug abuse
Reward pathway
**Mesolimbic dopamine system
- Dopamine from VTA (ventral tegmental area) —> Nucleus accumbens + Amygdala —> Prefrontal cortex
- Activation + Positive reinforcement effect
- Drug of abuse increase Dopamine activity in **Nucleus accumbens
Nucleus accumbens:
- Area for desire
Amygdala:
- Emotion
Hippocampus:
- Come later in stage of addiction
- ALL drugs of abuse activate Mesolimbic dopamine system
- Dopamine independent reinforcement occurs at the level of ***Nucleus Accumbens (e.g. cannabinoids CB1, serotonin (opiates increase 5HT in NA))
- When reinforcers are too powerful, natural drives (e.g. eating, work, sex) may be subsumed —> ignored
Tolerance and Withdrawal
Neuroplasticity:
- Adaptations in receptors + post-receptor mechanisms (e.g. change number of receptors) —> Tolerance
Withdrawal:
- Activation of extended ***Amygdala
- Major neurotransmitters: CRF, NE
- Major projection: Hypothalamus, Brainstem —> Physical symptoms of withdrawal
Craving / Preoccupation / Relapse
Key element of relapse in human:
1. Drug seeking induced by drug / stimuli paired (i.e. cue e.g. seeing the needle) with drug taking
2. Drug seeking induced by an acute stressor / a residual negative emotional state, often a state of stress (aka protracted abstinence)
Neurobiology:
- Conditional reinforcement in **Amygdala (associated with emotion)
- Contextual information processing by **Hippocampus
- Executive control depends on **Prefrontal cortex (ability to inhibit emotion / control activity)
- Major neurotransmitter: **Glutamate
Relapse:
- Strong conditional reinforcement + A lot of contextual information + Impaired executive control —> Push towards Relapse
Personality + Environmental involvement in Substance abuse
Controversial:
- Sensation seeking
- Impulsive
- More extrovert
—> Predispose to experiment with licit / illicit drugs
- Obsessional
- Dependent
- Anxious
—> More likely to get dependent + difficult to stop
Animal experiment:
- Socially housed
- More dominant
—> More D2 receptors in brain, less likely with cocaine use
- Individually housed
- More subordinate
—> Less D2 receptors in brain, more likely with cocaine use
Assessment of Substance abuse
Aims of assessment:
1. Make diagnosis
- Differentiating the drug using problem
- Formulation (What, Why, How)
- Understand the problems/difficulties (**Impact)
- Understand the **needs
- Understand the **person
- **Why the patient take drugs? - Facilitating treatment plan
- Based on ***Stage of changes
- Make diagnosis
- Based on diagnostic criteria
- Tolerance
- Withdrawal (physical / psychological)
- Compulsion of act - Drug screening / testing
- Tools e.g. **CAGE as screening questionnaire for alcohol misuse
- Have you ever felt you should **cut down on drinking?
- Have people **annoyed you by criticising your drinking?
- Have you ever felt bad / **guilty about your drinking?
- Have you ever had a drink first thing in the morning to steady your nerves / get rid of hangover? (i.e. **Eye-opener)
—> **>=2 positive indicate positive test —> further assessment
- Formulation (What, Why, How)
Impact:
1. **Medical impact
(Faster the drug reach their target site in the brain: better they are liked + more psychologically reinforcing)
- Impact of **Route (i.e. on body)
—> Ingestion
—> Inhalation / Smoking
—> Injection (SC, IM, IV)
- Impact of **Form / Substances (state of intoxication / withdrawal)
- Impact of **Chronic use
- Impact on ***Self care
- Psychological impact
- ***Comorbid mental health problems
—> Anxiety
—> Depression
—> Psychosis
- Motivational problems
- Insomnia - Social impact
- Relationship
- Housing
- Work
- Finance
- Criminal activity
Needs (Patient’s subjective needs + Doctor’s thought on patient’s needs):
1. Medical
2. Psychological
3. Social
Person:
1. Personality
2. Resources (∵ stressors is an important triggering factor for relapse)
—> Coping methods
—> Support network
3. Other problems
4. Subjective understanding, views, needs
Why the patient take drugs?
- Important part of assessment ∵ lead to effective treatment
—> Indicate future trigger factor for relapse
Reason can be dynamic (i.e. change over time)
1. High and buzz, Pleasure seeking (20%)
2. Self-medication for anxiety (social anxiety, anger, pain, boredom, lack of confident, lack of motivation etc.)
3. Psychiatric problem: depression, SE of some drugs, anxiety-related problems
4. Social pressure: peer effect, life events, adversity
5. Search for meaning / mystical experiences (e.g. connect to spiritual world)
