Substance misuse psychiatry Flashcards
Explain why alcoholic seizures can occur when dependent drinkers suddenly stop drinking.
Alcohol is a CNS depressant that works by stimulating the inhibitory GABA system. When dependent drinkers stop drinking the neural pathways become hyperexcitable and seizures can occur. These are generalised tonic-clonic seizures.
In extreme cases of alcohol withdrawal patient’s can get delirium tremens. What is this?
Delirium tremens is a medical emergency. It is the presence of a hyperadrenergic state with severe agitated confusion that can appear 48-72 hours after alcohol has been stopped. It is characterised by confusion, delusions, hallucinations (usually visual - of people and animals), affective changes such as alternation between extreme fear and hilarity, gross tremor, sweating, tachycardia, hypertension, dilated pupils and fever.
What blood results would raised suspicion of recent alcohol abuse/alcoholic liver disease?
Isolated or disproportionate elevation of gamma-GT compared to other liver enzymes (such as ALP or ALT).
What percentage of alcohol-dependent patients develop clinically relevant symptoms of withdrawal?
50%
What is the recommended pharmacological method of alcohol detoxification? Name specific drugs
- A reducing benzodiazepine regime is used. Usually, chlordiazepoxide (a long-acting benzo) - an alternative is diazepam.
- And thiamine - vitamin B1 - is prescribed as prophylaxis against Wernicke’s encephalopathy. Usually in the form of IV Pabrinex.
Which blood investigations would you carry out in a patient with suspected alcoholism. Describe the expected results.
FBCs and LFTs.
- FBCs: You would expect a macrocytic anaemia, i.e. raised MCV due to B12 deficiency.
- LFTs: Raised gamma-GT with recent heavy alcohol use and raised transaminases suggestive of hepatocellular damage.
Name an anti-craving drug used to prevent relapse in alcholics
Acamprosate. (This can be given to help intense anxiety, insomnia and craving, but is contraindicated in pregnancy and severe liver failure).
Which drug is used to treat chronic alcohol dependence by causing extremely unpleasant side effects such as flushing, throbbing headache and palpitations when alcohol is ingested? And how do these effects occur?
Disulfiram (antabuse) is used and it causes these effects due to acetaldehyde build up.
What causes Wernicke’s Encephalopathy and how does it present?
Wernicke’s Encephalopathy is caused by acute thiamine deficiency. It presents with a classic triad of: confusion, ataxia (wide-based gait) and ophthalmoplegia.
How is Wernicke’s encephalopathy treated and what does it lead to if left untreated?
It’s treated with urgent IV thiamine (Pabrinex). If there is coexistent hypoglycaemia, thiamine must be given BEFORE glucose. If left untreated, Wernicke’s encephalopathy can lead to irreversible Korsakoff’s syndrome.
Name three symptoms of Korsakoffs
Anterograde amnesia, some retrograde amnesia and confabulation.
Name four ‘local’ complications of IV drug use and three systemic complications.
Local: 1) Abscess formation 2) Cellulitis 3) DVT (repeated injection into femoral veins damages valves and slows venous return) 4) Emboli
Systemic: 1) Septicaemia 2) Infective endocarditis 3) Blood borne infections such as HIV and Hepatitis B&C
Opiate intoxication can be identified by what sign in the eyes?
Pin point pupils
Withdrawal from IV heroin use can be remembered as “everything runs”. What are the symptoms?
Diarrhoea, vomiting, lacrimation and rhinorrhoea. Dysphoria & agitation also occur. (Remember withdrawal is extremely unpleasant but rarely life threatening).
What drugs are used in substitute prescribing for heroin addicts?
Methadone (liquid) and buprenorphine (sublingual tablet).
