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Flashcards in Substance misuse Deck (73):
1

Biological factors in aetiology of substance misuse

Genetic predisposition (up to 50% heritability)

Neurobiological differences in EEG activity

Differences in receptor systems (e.g. DA) in brain

2

Psychological factors in aetiology of substance misuse

Personality: Anxious (incl disorder, esp social anxiety), Impulsive (e.g. in ADHD)

Psychiatric Hx (esp childhood): depression, PD

Positive reinforcement: Drugs lead to behaviours that increase their use

3

Social factors in aetiology of substance misuse

Social network: Key component of recovery, peer pressure, FHx of substance use

Legal: Price/availability/illegal status

Social norms: Acceptability

Social status: Isolation, unemployment, relationship issues

4

ICD-10 criteria for substance dependence

3 or more of the following:

Tolerance

Withdrawal/drinking to stop withdrawal

Compulsion to drink

Persistent drinking in the face of harm

Loss of ability to control drinking (reinstatement after abstinence)

Neglect of other activities

5

ICD-10 criteria for 'harmful use' of substances

Clear evidence of harm to physical/mental health of user (i.e. already caused harm)

6

5 stages of change for stopping subtance abuse

7

Threshold for 'lower risk' drinking

<14 units per week

8

Threshold for higher risk drinking

>50 units pw for males

>35 units per week for females

9

Receptor systems affected by alcohol

GABA: Acts as agonist, responsible for most effects

NMDA: Antagonist, reduces glutamate transmission

Opioid/DA: To lesser extents

Net effect: GABA > glutamate (acutely)

10

Psychopharmacology of chronic alcohol dependence

Compensatory increase in glutamate --> imbalance (glutamate >>> GABA) during withdrawal --> excitotoxicity

11

Screening tools for alcohol dependence

CAGE

FAST (4-question)

AUDIT (10 question)

12

What is the CAGE questionnaire?

Screening tool for alcohol dependence

Have you ever felt you should Cut down?

Annoyed by people criticizing your drinking?

Guilty about your drinking?

Eye-opener drink in the morning?

2+ = CAGE +ve

13

Assessment for alcohol use

  • Type of drink + quantity
  • Duration
  • Withdrawal/dependence signs
  • Full neuro, cognitive + liver (abdo exam)
  • LFTs (esp GGT), FBC (esp MCV, anaemia), Urate (in men), Carbohydrate-deficient transferrin
  • AUDIT, CIWA

14

FAST questions

  1. How often have you consumed >8/>6 units of alcohol in one sitting in the last year?
  2. How often have you failed to do what was expected of you due to drinking in the last year?
  3. How often were you unable to remember what happened the night before due to drinking in the last year?
  4. Has a relative, friend, or healthcare professional ever been concerned about your drinking or suggested you cut down?

15

Blood test changes associated with alcohol misuse

Unexplained macrocytosis

Unexplained LFT disturbance

Reduced platelets

Raised carbohydrate-deficient transferrin (identifies drinking in past 1-2 weeks)

16

Medical harm from alcohol

Liver: Damage, cirrhosis

CV: Cardiomyopathy, HTN

GI: Pancreatitis, varices, peptic ulcer

Cancer: Mouth, throat, oesophagus, liver

Blood: Macrocytosis, anaemia, haemochromatosis

17

Neurological harm of alcohol misuse

Blackouts

Epilepsy

Wernicke/Korsakoff syndrome

Neuropathy

Cerebellar degeneration

Dementia

Fetal alcohol syndrome

18

Psychiatric harm of alcohol misuse

Alcoholic hallucinosis: auditory, occurs in clear consciousness c.f. withdrawal

Suicide (10% of alcohol dependent)

Anxiety

Depression

Pathological jealousy

19

Features of acute alcohol withdrawal

Tremors

Sweating

Nausea/vomiting

Agitation/anxiety

Seizures

Auditory hyperacusis

Visual disturbances

Delirium tremens (5%)

20

Screening tool for alcohol withdrawal

CIWA-Ar

21

Onset of alcohol withdrawal symptoms

4-12h after last drink, lasts 2-5d

22

Rationale for pharmacological detox during acute alcohol withdrawal

Give benzodiazepine (usually chlordiazepoxide) for 5-7d in reducing dose to allow GABA/GLU balance to normalise

23

Chlordiazepoxide alternative in severe liver failure

Oxazepam, lorazepam (shorter half-life --> less liver accumulation)

24

Pharmacological management of acute alcohol withdrawal

10-30mg chlordiazepoxide qds (up to 50 for severe dependence) in reducing dose for 7 days

25

Autonomic features of delirium tremens

Autonomic:

  • Sweating
  • Pupil dilation
  • Hypertension, tachycardia, instability
  • Insomnia
  • Dehydration + electrolyte disturbance --> fatal arrhythmia 

26

Neurological features of delirium tremens

Coarse tremor

Delirium - confusion, disorientation

27

Psychiatric featurers of delirium tremens

Classic triad:

  • Transient persecutory delusions, paranoia
  • Visual hallucinations
  • Fear/agitation

28

Onset of delirium tremens

24-48 hours (but up to 7d) after cessation of drinking, usually with intercurrent illness (e.g. UTI)

29

Management of delirium tremens

Physical:

  • ECG + electrolytes --> fluid/haemodynamic management
  • Treat inter-current illness

Pharmacological:

  • Oral/IM lorazepam for sedation
  • Optimise detox medication (raise dose)

General:

  • Low-lit, quiet environment
  • 1:1 nursing
  • Inform security
  • MCA assessment + plan

30

Pathophysiology of wernicke's syndrome

Acute encephalopathy due to vitamin B1 deficiency leading to degeneration of mamillary bodies + frontal lobe white matter

31

Features of wernicke's syndrome

Delirium

Ataxia

Ophthalmoplegia/nystagmus

Hypothermia/hypotension, tachycardia

Neuropathy

32

Treatment of wernicke's encephalopathy

IV thiamine (Vitamin B1) for 3-7d (beware risk of anaphylaxis)

Oral thiamine for 1/12

33

Prognosis for Wernicke's

20% mortality

80% of survivors develop Korsakoff's

34

Differential causes of Wernicke's

Brain tumour

Prolonged vomiting: hyperemesis gravidarum in pregnancy, chemotherapy

Malabsorption syndromes

35

Clinical features of Korsakoff's

Anterograde amnesia

Some retrograde amnesia --> islands of memory

Confabulations

Due to damage of hippocampus/mamillary bodies

36

Management of Korsakoff's

Thiamine for 2 years

OT assessment + ongoing support

37

Prognosis of Korsakoff's

20% complete recovery

25% significant recovery

55% no change

38

How should you treat hypoglycaemia in alcohol-dependent patient

Give IV thiamine first to prevent precipitating Wernicke's

39

Role of acamprosate in treatment of alcohol misuse

Enhances GABA transmission

Reduces cravings but pt must not be drinking

Started on day 1 of detoxification

40

Role of naltrexone in alcohol misuse treatment

Blocks opioid --> reduces reward from alcohol 

Can be taken while not abstaining (e.g. prophylactically before big night)

41

Role of disulfiram in alcohol abuse treatment

Blocks acetaldehyde dehydrogenase --> increase acetaldehyde --> flushing + headache + hypotension

Threat of unpleasant consequences --> -ve reinforcement of alcohol drinking

Should not be used in severe liver damage, recent heart disease, suicidal ideation

42

Prognosis of relapse in alcohol misuse

50% relapse within 6 months

43

FRAMES approach to drinking interventions

Feedback about drinking

Responsibility of pt for change emphasised

Advice on how to stop drinking given

Menu of options for stopping drinking

Empathy

Self-efficacy of patient --> empowering

44

Management of alcohol dependence, biological

  • Withdrawal: Inpatient detox, community detox with benzo/thiamine
  • Relapse prevention: Bio
    • Pharmacological: Disulfiram, acamprosate, naltrexone, nalmefene
    • Vitamin supplementation

45

Management of alcohol dependence, psychological

Psychoeducation: Family, patient, safe drinking/withdrawal advice, self-help guidance

Consultation: FRAMES, motivational interviewing (decisional balance, readiness ruler)

Outpatient f/u: screen for co-morbid psychiatric condition

Turning point

Marital/family therapy

46

Management of alcohol dependence, social

Employment, social support

Residential/therapeutic communities (e.g. AA)

47

Positive prognostic factors for alcohol dependence

Strong motivation

Strong social/occupational structure

Good insight

48

Indications for inpatient detox

  • Alcohol Hx:
    • Past Hx of seizures/DT
    • Hx of failed community detox
    • Severe alcohol dependence
  • Current psych:
    • Symptoms of Wernicke's-Korsakoff
    • Current confusion/delirium
    • Polysubstance misuse
    • High suicide risk
    • Lack of stable home environment
  • Current physical
    • Severe malnutrition/N+V
    • Concurrent physical/psychiatric illness
    • Older age

49

Effects of cannabis intoxication

Anxiety, paranoia

Mellowness, giggling

slurring of speech, reduced coordination

Reddening of eyes

50

Active substances in cannabis

THC (main active ingredient) + cannabidiol (mild antagonist to THC, antipsychotic)

Levels vary in different strains

51

Adverse effects of cannabis

Increased risk of pneumothorax

Precipitate angina

Worsen schizphrenia prognosis

Precipitate schizophrenia

Cognitive impairment in long-term heavy users

Reduced concentration, memory, motivation

Sleep disturbance

52

Effects of opioids

Euphoria

Analgesia

Pupillary constriction

Respiratory depression, hypotension, hypothermia, bradycardia

N+V, constipation

53

Features of opioid withdrawal

GI: Vomiting, diarrhoea, abdominal pain

Face: Pupil dilation, runny nose + eyes

Neuromuscular: Restlessness, insomnia, myalgia

Autonomic: Sweating, tachycardia

Onset 6h after last dose, peak 36-48h

54

First-line treatment for symptomatic relief of opioid withdrawal

Lofexidine

55

Onset of opioid withdrawal

8-12h after last dose

56

Duration of opioid withdrawal

10d, with peak at 24-48h

57

Adverse effects of opioids

Infection: Phlebitis, HIV, HCV

Psychiatric: 14x risk of suicide

Overdose

Mortality 12x

Social: Crime, poverty, etc..

58

Pharmacological management of opioid dependence

Methadone

Buprenorphine

59

Dosing of methadone

Oral, start 30mg and increase slowly to reach therapeutic dose (60-120mg)

High risk of overdose!

60

Benefits of buprenorphine over methadone

Partial agonist --> ceiling effect --> lower risk of OD + less sedating

May ppt withdrawal during conversion

61

Psychological interventions for opioid dependence

Relapse prevention therapy (CBT)

NA programme

Residential programmes (therapeutic communities)

62

Relapse rate opioid dependence

40% at 6 months

63

Symptoms of opioid overdose

Respiratory depression/arrest

Pinpoint pupils

Bradycardia, hypotension

64

Management of opioid overdose

Naloxone until spontaneous ventilation returns

65

Features of stimulant use (amphetamines, cocaine, MDMA)

Elevated mood, energy, insomnia

Over-talkativeness

Pupil dilation, tachycardia, high BP, dry mucous membranes

Hyperpyrexia + dehydration (esp MDMA)

66

Features of amphetamine withdrawal

Depression, lethargy, suicidality, craving

67

Psychiatric effect of prolonged amphetamine use

Paranoid psychosis

Mood swings + depression

Formication (somatic hallucination) --> scabs

68

Management of acute stimulant misuse

Benzo and/or antipsychotic

TCA for depression if necessary

69

Effects of ketamine intoxication

Euphoria

Synaesthesia, hallucinations

Nausea

Ataxia, slurred speech

70

Adverse effects of ketamine

Fatal overdose

Permanent bladder damage (haemmorhagic cystitis)

Physical dependence

Psychosis, depression

Memory impairment

71

Management for harmful substance use, biological

Bio:

  • Monitor physical health issues (eg. infx)
  • Substitute prescribing/withdrawal management
  • Contraception, needle exchange

72

Management for harmful substance use, psychological

Education

Self-help, SMART goal setting

Treatment of underlying psychiatric conditions

Marital/family therapy

73

Management for harmful substance use, social

Employment/accommodation support (assigned social worker)

Help establishing new interests

Peer support group (e.g. NA)