Addiction Flashcards
How do addictive substances work to cause addiction?
Increase the amount of dopamine in the reward pathway
This increases activity in the orbito-frontal cortex and reduces activity of the pre-frontal cortex
This increases substance taking and seeking behaviour
What are the functions of the orbito-frontal cortex and the pre-frontal cortex?
Orbito-frontal cortex is involved in producing motivation to act
Pre-frontal cortex is involved in guiding behaviour and keeping impulses under control
What is tolerance?
When increasing amounts of a substance are needed to achieve the same effect
Why does tolerance occur?
Increased amount of dopamine in the reward pathway causes down-regulation of dopamine D2 receptors
What is intoxication?
The dose dependent direct physiological effects of a substance
What is classed as ‘harmful use’ of a substance?
A pattern of substance misuse that results in damage to either physical or mental health
What are the features of dependence syndrome?
Cravings Loss of control Withdrawal Tolerance Preoccupation Persistent use despite harm Rapid reinstatement after period of abstinence
What are cravings?
The strong desire to take a substance
What is loss of control with regards to addiction?
A person is unable to control when or how much of a substance is taken
What is withdrawal in addiction?
Physical symptoms that occur during a period of abstinence with associated use to avoid such symptoms
What is preoccupation with regards to addiction?
Prioritisation of substance use, which results in neglect of other activities or interests
What is the recommended weekly intake of alcohol?
14 units spread evenly across the week with several alcohol free days
What is a calculation to determine the units in an amount of alcohol?
(Millilitres of drink x %alcohol) / 1000
What is classed as binge drinking?
Males: >8 units per sitting
Females: >6 units per sitting
What is classed as hazardous drinking?
Audit 8-14
Drinking over the recommended amount but currently not experiencing any alcohol related problems
What is classed as harmful drinking?
Audit 15-19
Current drinking habits have resulted in physical or mental health complications
>35 units per week
What is classed as dependency?
Audit >20
Consuming >15 units daily
High levels of alcohol use with at least 3 features of dependence syndrome
What are some complications of alcohol misuse?
Malnutrition Alcoholic liver disease, liver cirrhosis Barrett's oesophagus Mallory-Weiss tear Peptic ulcer disease HTN AF Stroke Peripheral neuropathy Wernicke's Korsakoff's syndrome Increased incidence of cancers Gout Psychiatric: depression, anxiety, suicidal ideation, delirium
When do symptoms of alcohol withdrawal occur, when do they peak and when do they resolve?
Occur 4-12 hours after last drink
Peak at 24-48 hours
(Most) resolve in 5-7 days
Why do alcohol withdrawal symptoms occur?
Due to chronic alcohol use causing an imbalance in neurotransmitters in the brain - increased GABA, decreased glutamate
What are the symptoms of alcohol withdrawal?
Overwhelming desire to drink Insomnia Anxiety, agitation, restlessness Shaking, sweating Tachycardia HTN Pyrexia Nausea ad vomiting Generalised seizures Delirium tremens
What is delirium tremens?
A severe, potentially fatal form of withdrawal seen in physical dependence
How common is delirium tremens?
5% of withdrawal cases
What is the onset of delirium tremens?
Within 2 days of abstinence
What are the symptoms of delirium tremens?
Same as withdrawal plus: Delirium Ataxia Course tremor Hallucinations and delusions
What is Wernicke’s encephalitis?
Acute onset degenerative inflammation of the brain due to thiamine (B1) deficiency
Why are alcoholics more susceptible to Wernicke’s encephalitis in withdrawal?
Due to the higher risk of malnutrition there is more risk of thiamine deficiency
In withdrawal metabolism increases but the body sometimes might not have the nutrient stores to support this
What are the symptoms of Wernicke’s encephalitis?
Delirium
Ataxia
Nysagmus
Ophthalmoplegia
What is Korsakoff’s syndrome?
Chronic memory impairment associated with thiamine deficiency and Wernicke’s
What are the symptoms Korsakoff’s syndrome?
Confabulations
Anterograde amnesia - they have short term memory loss which is compensated for by making up stories that they believe are true
What should be included in a history for alcohol dependence?
Current alcohol use Dependency screen Past alcohol history Consequences Insight and motivation
What are examples of assessments of a person’s drinking habits?
CAGE
AUDIT
FAST
Comprehensive assessment: severity of alcohol dependence questionnaire (SADQ, MMSE, full medical and psych history)
What is involved in brief intervention - and when is it given?
For hazardous or harmful drinking Feedback (of problems due to alcohol) Responsibility (patient for change) Advice Menu (options for change) Empathy Self-efficacy (encourage optimism)
What motivational interviewing - and when is it done?
For harmful drinking
Assessment of how motivated a patient is for making a change
Encouragement towards the realisation that they need to change their drinking habits
When is medically assisted withdrawal done?
For dependency
When is medically assisted withdrawal done inpatient?
Severe dependence
History of delirium tremens or withdrawal seizures
History of failed community detoxifications
Poor social support
Psychotic co-morbidity
Poor physical health
When is specialist treatment given for medically assisted withdrawal?
Moderate or severe dependence
If brief advice and motivational interviewing haven’t worked and they want further help
If severe alcohol-related impairment or related co-morbid condition
What does specialist treatment for medically assisted withdrawal involve?
Detoxification and relapse prevention using prescription medications
Which benzodiazepines are used in medically assisted withdrawal?
Diazepam
Chlordiazepoxidine
How are benzodiazepines used in medically assisted withdrawal?
Reduce gradually over 7 days or more
Titrate against severity of withdrawal symptoms
How do benzodiazepines help in medically assisted withdrawal?
Sedate patient and make physical and psychiatric symptoms less traumatic
Why are B12 and other vitamins given in medically assisted withdrawal and how are they given?
Reduces likelihood of Wernicke’s encephalopathy
Need to be given IV due to malnutrition being associated with villous atrophy and reduced absorption
What are the pharmacological options for relapse prevention - and which is first line?
Naltrexone - first line
Disulfiram
Acamprosate
What is naltrexone and how does it help relapse prevention?
Opioid agonist
Reduces reward from alcohol
What are some physical risks in opiate misuse?
Skin infection DVT Blood-borne viruses Damage to nasal mucosa Physical dependence Anxiety, depression, psychosis Benzodiazepines - seizures
What are signs of an acute overdose?
Pinpoint pupils Decreased GCS Respiratory depression Hypotension Bradycardia
What is the management of an acute opiate overdose ?
Naloxone
Respiratory support
What are symptoms of withdrawal from opiates?
Goosebumps Dilated pupils Tachycardia Hypertension Agitation Sweating Abdominal pain Diarrhoea
What are the management options for relapse prevention of opiate addiction?
Opioid replacement therapy
Psychosocial intervention, counselling and input from other agencies
What is opioid replacement therapy?
Deliberate prescribing of opioid drugs in a controlled manner to introduce some order and control into lifestyle
What is the process of opioid replacement therapy?
Induction
Optimisation
Maintenance
Dose reduction
What drugs are options for opioid replacement therapy?
Methadone
Buprenorphine
Clonidine/Lofexidine
What are the features of methadone?
Opioid agonist Long half life Can prolong QT interval Can cause sedation High dependence and low lethal dose
What is the treatment for overdose of methadone?
Narcan
