Define intoxication.
a dose dependent, transient state following drug use
Define harmful use.
a pattern of use likely to cause physical or psychological damage
Define dependence.
needing to use a substance to feel or function normally, after a period of regular use
What are the features of dependence?
Describe the epidemiology of substance misuse.
Define binge drinking.
>8 units for men or >6 units for women in one session - constitutes 27% of UK alcohol consumption.
What is the aetiology behind substance use disorders?
Describe the genetic aspect behind behind substance use disorders.
Describe the childhood and life experiences behind substance use disorders.
RFs:
Describe the role of occupation in substance use disorders.
Describe the role of psychiatric illness in substance use disorders.
Substance use disorders are associated with:
What are the 2 broad theories of dependence?
Describe the learning theories of dependence.
Classic (Pavlovian) Conditioning
Operant (Skinnerian) Conditioning
•Behaviours which are rewarded are repeated (positive reinforcement), and also behaviours which relieve unpleasant experiences (negative reinforcement)
Vicarious Learning
• Substance dependence can develop following observation of behavioural rewards in others as well as direct experience
Motivational Theory
Relapse isn’t ‘failure’, but a learning opportunity: under-standing the triggers for relapse helps the next attempt at abstinence
Describe the neurobiological models of dependence.
Most addictive drugs strongly increase synaptic dopamine levels in the reward pathway.
Describe the clinical presentation of alcohol use.
•Intoxication
o Slurred speech, poor coordination, exaggerated emotions, ataxia, increasing sedation and confusion
Severe intoxication (‘alcohol poisoning’) can cause vomiting, ataxia, respiratory depression, confusion, coma, and death.
•Withdrawal
o Headache, nausea, retching and vomiting, tremor and sweating
o Insomnia
o Anxiety, agitation, tachycardia and hypotension
Severe withdrawal causes delirium tremens or death
How can we divide the complications of alcohol use disorder?
What are the physical complications of harmful alcohol use?
Liver: alcoholic hepatitis (malaise, hepatomegaly and ascites)
GI: pancreatitis, oesophageal varices, gastritis and peptic ulceration
Neurological: peripheral neuropathy, seizures and dementia
Cancer: bowel, breast, liver, oesophageal
CV: htn and cardiomyopathy
Head injuries and accidents while intoxicated – increased risk subdural haematoma
Fetal alcohol syndrome
What are the physical complications of harmful alcohol use?
What is Wernicke-Korsakoff syndrome?
Wernicke encephalopathy
o Irreversible anterograde amnesia (and some retrograde)
o Patient can register new events, but cannot recall them within a few minutes o Patients may confabulate to fill gaps in memory
What is delirium tremens? What are the symptoms, mortality and management?
Medical emergency
Onset: ~48h into abstinence
Part of severe alcohol withdrawal
Onset around 48 hrs into abstinence; Duration: 3-8 days
Symptoms
o Confusion
o Hallucinations, especially visual (animals and people) and tactile (itch, burn, crawling up skin)
o Affective changes – extreme fear and hilarity may alternate
o Gross tremor (hands)
o Autonomic disturbance: sweating, tachycardia, htn, dilated pupils, fever o Delusions
5% mortality rate (30% if complications occur)
Urgent medical treatment involves a reducing benzodiazepine regime and parenteral thiamine
o Mx dehydration and electrolyte imbalance
What are the psychiatric complications of harmful alcohol use?
What are the social complications of harmful alcohol use?
What is the progression of alcohol withdrawal?
Alcohol withdrawal
What is the differential diagnosis of alcohol use disorder?
Organic: head injury and subdural haematoma
Psychiatric illness
o Often a dual diagnosis
o Depression/mania
o Functional psychosis
o Anxiety disorder
o Personality disorder