Substance Misuse Flashcards
What are the ICD-10 criteria for substance misuse?
Acute intoxication Harmful use Dependence syndrome Withdrawal state Psychotic disorder Amnesic syndrome Residual disorder
What is the pathophysiology behind substance misuse?
Biological and environmental factors leads someone to take a substance, this causes positive reinforcement which then leads to dependence over time.
What is meant by positive reinforcement?
Reinforcement is what makes you to continue taking the drug which then eventually leads to dependence, reinforcement is either psychosocial reinforcement (from peers or the pleasurable effects of the drug) and biological reinforcement (activates mesolimbic dopaminergic reward pathways)
What is the epidemiology behind substance misuse?
Substance misuse is more common in males than females at a ratio of 3:1
Cannabis is the most used drug (5% of the population)
What are the clinical features of substance misuse?
Physical- death, infection (HIV, Hep A, B, C, staph aureus, group A streptococci, clostridium, TB), endocarditis, superficial thrombosis, DVT, PE)
Psychological- craving, anxiety cognitive disturbance, drug induced psychosis
Social- crime, imprisonment, homelessness, prostitution, relationship problems.
What is substance dependence?
Describes a syndrome including behavioural, physiological and psychological elements, patients are physiologically dependent if they show tolerance or withdrawal
> or equal to 3 of the following manifestations must have occurred over 1 month…
. Strong Desire (compulsion) to consume a substance
. Preoccupation with substance use
. Withdrawal state when substance ingestion is reduced or stopped
. Impaired ability to control substance taking behaviour
. Tolerance to substance, requiring more consumption for desired effect
. Persisting with use, despite clear evidence of the drugs Harmful events.
What questions should you ask in a drug user?
TRAP- trap, route, amounts pattern
Explore dependency- do you feel that taking the drug is on your mind, have you tried reducing the drug your taking, any problems with this? Able to control your consumption? Do you feel that you have to take more of the drug to get the same effect? Are you aware of the harmful effects? (Knowledge of harm)
Make sure to also carry out a risk assesment- suicide/self harm as well as IV use/needle sharing)
What are the investigations carried out for a person who’s misusing substances?
Bloods- HIV screen, Hep B, Hep C and TB testing (the risk of blood borne infections is thought to be greater in needle sharing), U and Es, to check for renal function, LFTs and clotting (checks hepatic function), drug levels
URINALYSIS- drug metabolites (cannabis and opioids) can be detected in the urine.
ECG- for arrhythmias, ECHO if endocarditis is suspected (secondary to needle sharing)
What is the differential diagnosis for substance misuse?
Psychiatric disorders- psychosis, mood disorders, anxiety disorders and delirium
Organic disorders- hyperthyroidism, CVA, intracranial haemorrhage, neurological disorders (cerebellar pathology)
What is the management of substance misuse?
Hep B immunisation must be considered for those at risk
Motivational interviewing to help with controlling substance misuse and CBT for co morbidities May be offered
Contingency management- this focuses on changing specified behaviours by offering incentives ie: financial for positive behaviours
Supportive help with housing, finance and employment
Smoking cessation should be offered
Self help groups
Review DVLA guidelines
What is the difference between detoxification and maintenance therapy?
Detoxification= the process in which the effects of the drugs are eliminated in a safe manner (a replacement drug is weaned) such that withdrawal symptoms are avoided in an attempt to attain abstinence.
Maintenance= abstinence is not the priority, rather the aim is to minimise the harm (eg: from IV drug use).
What are the drugs used for opioid dependence?
Methadone (1st line) or buprenorphine for detoxification and maintenance.
What is recommended in patients who were formerly opioid dependent but have now stopped and are motivated to continue abstinence?
Naltrexone
What can be used as an antidote to opioid overdose?
Intravenous Naloxone
What is the antidote for paracetemol overdose?
IV acetylcysteine
What is alcohol abuse?
Consumption of alcohol at a level sufficient enough to cause physical, psychiatric and/or social harm.
What is binge drinking?
Drinking over twice the recommended level of alcohol per day in one session (more than 8 units for a male and more than 6 units for a female)
What is the recommended limits of alcohol?
14 units per week
What is the pathophysiology behind alcohol?
Alcohol affects several neurotransmitters in the brain eg: it’s effect of GABA causes anxiolytics and sedative effects.
The pleasurable and stimulant effects of alcohol are mediated by a dopaminergic pathway in the brain, repeated and excessive alcohol ingestion causes a sensitisation in this dopaminergic pathway and leads to the development of dependence.
What happens pathologically when you are exposed to alcohol in the long term?
Causes adaptive changes in neurotransmitter systems, down regulation of inhibitory neuronal GABA receptors and up regulation of excitatory glutamate receptors so when alcohol is withdrawn it results in CNS hyper excitability.
What are the risk factors of alcohol abuse?
Male (are at an increased risk of alcohol abuse and have increased metabolism of alcohol and therefore they can have higher quantities) Younger adults Genetics Antisocial behaviour Lack of facial flushing Life stressors
What are the clinical features of alcohol intoxication?
Slurred speech Labile affect Impaired judgement Poor co ordination Severe cases: hypoglycaemia, stupor and coma
What are the clinical features of alcohol dependence?
Subjective awareness
Avoidance or relief of withdrawal symptoms ie: drinking more (also known as relief drinking)
Withdrawal
Drink seeking behaviour predominates
Reinstatement of drinking after attempted abstinence
Increased tolerance to alcohol
Narrowing of drinking repertoire
What are the symptoms of alcohol withdrawal?
Malaise, tremor, nausea, insomnia, transient hallucinations and autonomic hyperactivity occur at 6-12 hrs after abstinence
Peak incidence of seizures at 36 hours
What is delirium tremens?
The severe end of the spectrum of alcohol withdrawal, peak incidence is at 72 hours. It develops between 24 hours and one week after alcohol cessation.
What are the signed of delirium tremens?
Cognitive impairement Vivid perceptual abnormalities Paranoid delusions Marked tremor Autonomic arousal (tachycardia, fever, pupillary dilatation and increased sweating)
What is delirium tremens treated with?
Medical treatment can be with large doses of benzodiazepines (chlordiaxepoxide)
Haloperidol for any psychotic features and intravenous pabrinex.
What is the peripheral stigmata of chronic liver disease in alcoholics?
Palmar erythema
Dupuytrens contracture
Spider navel
Gynaecomastia
Other features; clubbing, capital medusa and oesophageal varices
What should you ask in a history of an alcoholic?
CAGE questionare
C= do you ever feel you should cut down on your drinking
A= have people annoyed you by criticising your drinking?
G= have you ever felt Guilty about your drinking?
E= do you ever have a drink early in the morning to steady your nerves or wake you up (eye opener)
. What drinks, how much in a week, how much money do they spend, how often, do you drink steadily or do you binge drink, is there anything that causes you to drink more
What investigations are important to do in an alcoholic?
Bloods- blood alcohol level, FBC (anaemia), Us and Es (test for dehydration which would be a decrease in urea), LFTS including gamma GT may be elevated, blood alcohol concentration, MCV (macrocytosis), vit B12/folate/TFTs (this is to look for alternative causes of a raised MCV), amylase to look for pancreatitis, hepatitis serology, glucose (hypoglycaemia)
Alcohol questionares
CT head
ECG (for arrhythmia)
What is the differential diagnosis for alcohol misuse?
Psychosis
Mood disorders (bipolar)
Anxiety disorders
Delirium
Head injury
Cerebral rumour
CVA (stroke)
What is Wernickes encephalopathy?
An acute encephalopathy which is due to thiamine deficiency, presents with delirium, nystagmus, opthalmoplegia, hypothermia and ataxia.
Requires urgent treatment and may progress to korsakoffs psychosis (AKA amnesic syndrome)
How do you treat wernickes encephalopathy?
Parenteral thiamine
What is korsakoffs psychosis?
Profound, irreversible short term memory loss with confabulation (unconscious filling of gaps in memory with imaginary events) and disorientation to time.
What is confabulation?
Unconscious filling of gaps in memory with imaginary events.
What is acute intoxication?
Acute, usually transient effect of the substance
What is amnesic syndrome?
Memory impairment in recent memory (impaired learning in of new material) and ability to recall past experiences. Also defect in recall, clouding of consciousness and global intellectual decline.
What is residual disorder?
Specific features (flashback, personality disorder, affective disorder, dementia, persisting cognitive impairement) due to substance misuse.
What is meant by disinhibition?
The inability to withhold a prepotent response or suppress an inappropriate or unwanted behaviour.
What are examples of opiates?
Morphine
Diamorphine (heroin)
Codeine
Methadone
What are the routes of the following…
1) morphine
2) diamorphine
3) codeine/methadone
1) can either be oral or IV
2) can be IN/IV/ smoked
3) oral
What are the psychological effects of taking opiates?
Apathy Disinhibition Psychomotor retardation Impaired judgement and attention Drowsiness Slurred speech
What are the physical effects of taking opiates?
Resp depression Hypoxia Decreased BP Hypothermia Coma Pupillary constriction
How would you recognise opioid withdrawal? (At least 3 signs are needed)
Craving Rhinorrhoea Lacrimation Myalgia N+V Diarrhoea Pupillary dilatation Piloerection Increase heart rate and blood pressure
What are the psychological effects of cannabinoids?
Euphoria Disinhibition Hallucinations Paranoid ideation Illusions Temporal slowing Impaired judgement time
What are the physical effects of cannabinoids?
Increased appetite
Dry mouth
Conjunctival injection (non specific response with enlargement of conjunctival vessels induced by various diseases).
Increased HR
What would the withdrawal state of cannabinoids present like?
Anxiety Irritability Tremor of outstretched hands Sweating Myalgia
What are examples of sedative hypnotics?
Barbiturates and benzodiazepines
What are the psychological effects of sedative hypnotics?
Euphoria Disinhibition Apathy Aggression Anterograde amnesia Labile mood
What are the physical effects of taking sedative hypnotics?
Unsteady gait Difficulty standing Slurred speech Nystagmus Erythematous skin lesions Decreased BP Hypothermia Depression of gag reflex Coma
How would you recognise withdrawal state of sedative hypnotics?
Tremor of hands, tongue, eyelids N+V Increased HR Postural decreased BP Headache Agitation Transient illusions Hallucinations Paranoid ideation Grand mal convulsions
What are examples of stimulant drugs?
Cocaine
Crack cocaine
Ecstasy (MDMA)
Amphetamine
What are the psychological effects of stimulants?
Euphoria Increased energy Grandiose beliefs Aggression Argumentative Illusions Hallucinations (intact orientation) Paranoid ideation Labile mood
What are the physical effects of stimulants?
Increased HR, BP, arrhythmia, sweating, N+V, pupillary dilatation. Psychomotor agitation, muscular weakness, chest pain, convulsions
How would you recognise a withdrawal state in someone taking stimulants?
Dysphoric mood Lethargy Psychomotor agitation Craving Increased appetite Insomnia or hypersomnia Bizarre or unpleasant dreams
