Substance misuse Flashcards
list the 4 categories of substance misuse?
Intoxication - emotional and behavioural change after drug use.
- Harmful use - use causing damage.
- Dependency
- Withdrawal
define dependency according to ICD-10?
a cluster of physiological, behavioural
and cognitive symptoms in which the use of a
substance takes on a much higher priority than other
behaviours that once had greater value - (ICD-10)
what is the ratio of substance and alcohol misuse in men vs women?
M:F
2:1 for alcohol disorders
• 4:1 for substances
what are the Main theories of dependence?
A. Learning theories
- Classical (Pavlovian) conditioning
- Operant conditioning
- Social learning theory (vicarious learning)
- learn from others/peer pressure
B. Neurobiological models
- drugs of reward affect reward pathway - dopaminergic
reward pathway
- pleasurable sensation from block of DA degradation
what is Classical (Pavlovian) conditioning?
cravings become conditioned to ‘cues’ (e.g. needles for heroin users), so
the cue itself can trigger cravings
what is operant conditioning?
Behaviours that are rewarded are repeated (positive
reinforcement
what is the effect of cocaine and amphetamines on the dopaminergic reward pathway?
block dopamine reuptake,
increasing synaptic dopamine levels, and causing a pleasurable sensation.
what is the effect of alcohol and opiates on the dopaminergic reward pathway?
increase dopamine
and affect other neurotransmitters.
outline the mechanism AND presentation of the ‘flush reaction’ ?
which ethnicity most affected?
Ethanol is metabolized to acetaldehyde,
which is then broken down by aldehyde dehydrogenase.
In East Asian populations,
a less effective variant enzyme occurs.
Acetaldehyde accumulates, causing flushing, palpitations, and nausea
list risk factors of alcohol misuse?
occupation
social background - difficult childhood
psychiatric illness - anxiety, depression etc
How can alcohol misuse present?
- Intoxication
- Withdrawal
intoxication;
irritable, aggressive, weepy,
morose, and disinhibited.
Impulsivity and poor judgement
Speech becomes slurred, the gait ataxic, and there may
be increasing sedation, confusion, and even coma.
withdrawal:
Headache, nausea, retching and vomiting, tremor, and
sweating are all typical. Insomnia.
anxiety, agitation, tachycardia, and hypotension
outline the mechanism of alcohol induced seizures?
Alcohol is a CNS depressant,
stimulates the GABA inhibitory system to reduce brain excitability.
When dependent drinkers suddenly stop drinking,
neural pathways
become hyper-excitable and seizures can occur.
what is the consequence in very severe cases of alcohol withdrawal?
Very
severe cases risk delirium tremens
a publican met an evangelist and has decided to take a new leash on life and quit 2 days ago. He is brought in with;
confusion
– hallucinations, especially visual, e.g. animals and people
– affective changes; extreme fear and hilarity may alternate
– gross tremor, especially of hands
– autonomic disturbance: sweating, tachycardia, hypertension,
dilated pupils, fever
– delusions.
diagnosis?
delirium tremens
how to manage a delirium tremens patient?
reducing benzodiazepine regime
and parenteral thiamine (so iv/im/sc NOT po)
rehydrate and fix electrolyte imbalance if any
what is the aetiology of Wernicke’s encephalopathy?
Caused by acute thiamine (vitamin B1) deficiency.
classic presentation of Wernicke’s encephalopathy?
what is the treatment?
triad of confusion, ataxia,
and ophthalmoplegia.
rx;
treat with parenteral thiamine:
IV thiamine given slowly (prevent anaphylaxis) +
IM thiamine for next 5 days
PO thiamine 6-12 after resolution of acute episode
classic presentation of Korsakoff’s syndrome ?
irreversible anterograde amnesia (and
some retrograde amnesia)
patient can register new events, but cannot recall
them within a few minutes.
Patients may confabulate to fill the gaps in their memory.
when does one get Korsakoff’s syndrome?
if wernickes is not treated with parenteral thiamine
what equates to a unit of alcohol for the following;
beer
wine
spirits
sherry
- half a pint of ordinary strength beer (3.5–4%)
• a small glass of wine (125mL)
• a standard measure of spirits (25mL)
• a standard measure of sherry/port (50mL)
what units are considered as binge drinking for
women/ men ?
women - more than 6 per day (35 a week)
men - more than 8 per day
list features of dependency?
Tolerance
Compulsion
Withdrawal
Problems controlling use
Continued use despite harm
Salience - other needs become neglected
Relapse/Reinstatement after abstinence
Narrowing of the repertoire - only use same type of substance, and style
outline the key areas of the dopaminergic ‘reward’
pathway in the brain?
where is DA released?
pathway starts in the ventral tegmental area (VTA)
and projects onto the prefrontal cortex
and limbic system (the ‘emotional’ brain).
Dopamine release in the nucleus accumbens -> sensation of pleasure -> reward.
which part of the brain has a role in motivation and
planning?
The prefrontal cortex
list some GI complications of excess alcohol consumption?
pancreatitis, oesophageal varices,
gastritis, and peptic ulceration.
list some CVS complications of excess alcohol consumption?
HTN
Cardiomyopathy
list some psychological complications of excess alcohol consumption?
Depression, anxiety, self-harm, and suicide are
increased.
• Amnesia (blackouts)
Cognitive impairment - occur, as either alcoholic
dementia or Korsakoff ’s syndrome
- Alcoholic hallucinosis - auditory hallucinations in clear consciousness while drinking alcohol, or after periods of heavy alcohol use.
- Morbid jealousy - delusion that a partner is unfaithful.
ivx for alcohol dependency?
results would show?
- FBC
– Alcohol causes a macrocytic anaemia (raised MCV)
due to B12 deficiency. - LFTs
– γGT rises with recent heavy alcohol use.
– Raised transaminases suggest hepatocellular damage. - Additional investigations e.g. an ECG for chest pain, a urine drug screen (UDS) if you suspect drug misuse, hepatitis screening if intravenous (IV) drug use.
what are the steps involved in alcohol dependency management?
- Assessment and preparation
- Assess motivation to change:
- > stages of change model
- motivational interviewing - Detoxification
- Relapse prevention
- psychological and medical means
- Rehabilitation
- finding work, restructuring of life etc
what are the steps of the stages of change model?
pre-contemplation
contemplation
preparation
- set SMART goals
action
maintenance
relapse - part of the learning experience
what is motivational interviewing?
Motivational interviewing (MI) is a form of counselling which aims to empower the person to change
how is alcohol detox conducted?
and where
iv/im/po?
Community
Admission - if risks of seizures or mental illness etc
Long-acting benzodiazepines (e.g. chlordiazepoxide)
replace alcohol and prevent withdrawal symptoms,
including seizures and delirium tremens. They are
gradually withdrawn and stopped.
• Thiamine (vitamin B1) is prescribed as prophylaxis
against Wernicke’s encephalopathy. It is best given
parenterally (IM or IV) since it is poorly absorbed in
the gut.
What strategies are used in relapse prevention?
Psych; CBT + group therapies
Meds;
1st line - Acamprosate is an anti-craving drug. if relpase into drinking, doesn’t work.
+ Disulfiram (Antabuse) mimics the ‘flush reaction’ to alcohol, making drinking highly unpleasant! causes severe reaction if they drink again.
Naltrexone
Used from 6months - 1 year
Check LFTs before use
what is the MOA of Cannabis?
thc-9-tetrahydrocannabinol acts on cannabiinoid receptors ini brain?
effects of taking cannabis?
enhances original mood state;
relaxation, euphoria
paranoia, anxiety
chronic heavy use of cannabis causes?
lethargy, poor motivation
describe hashish?
squidgy brwon/black lump - from resin and flowers
strongest cannabis form?
skunk
sidie effects of stimulant drugs?
cardiac arrhythmias
HTN
Stroke
Anxiety, Panic, Psychosis
a patient has presented having taken cannabis - a stimulant. how to treat?
harm reduction
short term Benzo
- helps with withdrawal anxiety
MOA of stimulants?
potentiate the effects of neurotransmitters
dopamine, noradrenaline, sometimes serotonin
what sensations are associated with cocaine use?
euphoria - its a stimulant
formification - insects crawling on or below skin
cocaine damages nasal mucosa because?
powerful vasoconstrictor
why is crack so addictive?
intense high lasts only 5/10 mins
what drug to give as replacement for iv amphetamine dependency?
dexamphetamine
for stabilisation and detox
which drug causes florid psychosis?
Khat
MOA of MDMA?
serotonin release and reuptake inhibition
its a cross between a stimulant and a hallucinogen (although hallucinations are rare).
define synaesthesia?
experiencing a sensation in another modality like hearing a smell
synaesthesia is common with the use of which drug type?
Hallucinogens
what does LSD stand for?
lysergic acid diethylamide
what are the effects of taking LSD?
side effects?
ingestion causes trips of up to 12 hours’ duration, with
perceptual changes and euphoria.
Bad trips - experiences become frightening and unpleasant.
side effects:
sudden flashbacks can occur, even years later.
anxiety, depression, and psychosis.
which drug comes as a liquid or powder that can be snorted or added
to a joint and smoked, and is associated with violent
outbursts and ongoing psychosis.
Phenylcyclidine (PCP, angel dust)
which drug causes anaesthesia ->
people have severely harmed themselves while hallucinating, e.g. pulling out their own teeth.
Ketamine
which drug group has sx at high doses similar to alcohol;
causing a feeling of calm and mild
euphoria, with slurred speech, ataxia, and stupor (or
even coma) at higher doses. Withdrawal effects are similar to alcohol, e.g. seizures ?
Benzos
rx for Benzo overdose?
flumazenil
which is a benzodiazepine antagonist.
list some risks associated with solvent use?
Spraying:
- Throat swelling
- Asphyxiation
Bag:
-Suffocation
Coma can occur and result in death if vomit
is aspirated.
how to spot someone on solvents?
Telltale signs are blistering and redness around the mouth and nose
hangover can occur afterwards with severe
headaches and fatigue
list some poor prognostic factors for abstinence from drug use?
Intravenous drug use,
chaotic use,
polydrug use
How would you assess alcohol dependency in a patient?
- AUDIT questionnaire
if result suggests depence then do the
- SADQ - seveerity of alcohol dependence OR
- LDQ - leeds dependence questionnaire
how do you initially screen if the patient requires an in depth alcohol screen?
CAGE questionnaire
C Have you ever felt that you should cut down on your
drinking?
A Have people annoyed you by criticizing your drinking?
G Have you ever felt guilty about your drinking?
E Have you ever had a drink first thing in the morning, to
get rid of a hangover? eye-opener
list mild, moderate and severe alcohol withdrawal sx?
mild - emotional sx, fine tremor, insomnia
moderate - mild sx more prominent, coarse tremor, agitation
severe - tonic clonic seizures, delirium/confusion, hallucinations, hyPERtheremia
list withdrawal sx from stimulants i.e cocaine, amphetamine?
CRASH -> depression, lethargy
what do withdrawals from benzo’s look like?
similar to alcohol including seizures
list withdrawal sx from opiates?
everything runs!
- diarrhoea, vomiting, lacrimation, rhinorrhea
Yawning dysphoria aches, cramps, sweating dilated pupils insomnia
etc
colloquial names for heroin?
(diamorphine, brown, smack, horse, gear, H)
what is the MOA of heroin?
Heroin is a μ (mu) opiate agonist,
stimulating brain and spinal
cord receptors that are normally acted upon by endogenous
endorphins (the body’s natural painkillers).
list local and systemic complications of ivdu?
local; abscess cellulitis DVT Emboli
systemic; septicaemia infective endocarditis blood-borne infections - hep b,c,hiv (hep c most common) overdose
how does heroin kill?
bradycardia and respiratory depression ->
aspiration of vomit in OD
Managment of opiate dependency?
- Harm reduction
- needle exchange, blood virus screening - Substitute prescribing
- methadone - liquid
- buprenorphine - sublingual tablet
(this is used for current addicts to get them off heroin, given until no longer experiencing withdrawal, wean off over weeks/months)
2b. Adjuncts (used to aid detox)
- Loperamide (4 diarrhoea)
- anti-emetics (metoclopramide)
- non-opiate pain killers
- Naltrexone
- Blocking drug
- Given post detox to prevent relapse
MOA of methadone?
why is it used for decency?
full agonist at opiate mu receptors
longer half lofe than heroin = withdrawal longer and milder
MOA of buprenorphine?
when is it preferred?
partial agonist at opiate mu receptors
blocks heroin euphoric effects, prevents withdrawal
preferred in:
- users with bad expereicnce iwth methadone
- want clear head
- on cyp450 inducers; anticonvulsants etc
- want to quit heeroin completely
when does Withdrawal following IV heroin use typically begin?
around 6 hours after injection; peaking at 36–48 hours
a patient is prescribed methadone, detoxification is then commenced. patient detriorates on detox. what is the best course of action?
Keep patient on a maintenance regime of Methadone so that they at least have stability;
can get and maintain a job etc etc
what is the MOA of naltrexone?
Naltrexone is an opiate antagonist that blocks opiate
receptors and thus the euphoric effects of opiates.
what is the COAT rack of wernicke-korsakoffs syndrome?
C - confusion
O - opthalmoplegia
A - ataxia
T - thiamine deficiency
R - retrograde amnesia
A - anterograde amnesia
C - confabulation
K - korsakoff psychosis
in the treatment of wernicke’s what is one alternative to thiamine that could be preferable? why?
Pabrinex
contains nicotinamide, riboflavine, pyridoxine and ascorbic acid along with thiamine, is
often preferable to thiamine alone as this will cover the possibility of other vitamin deficiencies.
what is charles bonnet syndrome?
visual hallucinations secondary to visual impairment
if a patient undeergoing detox self discharges, what advice to give them?
cant give them chlordiazepoxide - only used in hospitals
tell them they must continue drinking, cant stop completely due to risk of seizures
tell them to seek further help when they feel ready - gp
refer to alcohol liason nurse/services -> can be followed up in the community
if a patient undeergoing detox self discharges, what advice to give them?
cant give them chlordiazepoxide - only used in hospitals
tell them they must continue drinking, cant stop completely due to risk of seizures
tell them to seek further help when they feel ready - gp
refer to alcohol liason nurse/services -> can be followed up in the community
treatment of opiod overdose?
IM naloxone
