Addiction Psychiatry Flashcards
which pathway in the brain is affected in addiction
mesolimbic - reward pathway
what structures of the brain make up the mesolimbic pathway
ventral tegmental area
nucleus accumbent
pre-frontal cortex
when a certain chemical is produced, its produces a motivating signal and you want that thing more, what chemical is produced
dopamine
what is the function of the hippocampus, striatum and amygdala
learning and memory - responsible for habits and cues
what is the function of the pre-frontal cortex
puts brakes on the reward pathway
how does behaviour change in response to addiction
normally, dopamine is released with pleasurable experiences
in addiction, receptors downregulate and more of the substance is required to produce the same desired effect
what 6 features must be present for a diagnosis of dependence
craving
tolerance
withdrawal - physical symptoms when stopping
loss of control
persistence despite harm
preoccupation - doesn’t enjoy other things
what are the complications of IV drug use
infection - local, distant and systemic
DVT and PE
describe the features associated with heroin use
euphoria respiratory depression reduced consciousness bradycardia analgesia constipation hypotension
what is the pupillary change seen in heroin use
pin point pupils
describe the features associated with heroin withdrawal
approx 6 hours after use diarrhoea hypertension dilated pupils piloerection agitation tachycardia nausea and vomiting lacrimation and rhinorrhoea
what is the main treatment for opiate misuse
opiate substitution therapy
what is the first line opiate substitution and what is its mechanism
methadone - long acting full agonist
what is the second line opiate substitution and what is its mechanism
buprenophine - long acting partial agonist
what is the recommended limit for alcohol consumption for men and women
14 units per week spread across several days with some alcohol free days
how do you calculate the number of units in a drink
(mls of drink x % of alcohol) / 1000
define binge drinking
> 6 units in a sitting if female
>8 units in a sitting if male
define hazardous drinking
audit score of 8-14, drinking more than recommended but not experiencing any alcohol related problems
define harmful drinking
audit 15-19, drinking habits have resulted in physical or mental health complications
define alcohol dependency
audit >20 or >15 with at least 3 features of dependency
list some of the screening tools available for assessing alcohol use
AUDIT
CAGE
TWEAK
PAT and FAST
describe the AUDIT
10 questions on hazardous drinking
describe the CAGE
4 questions C - cut down A - annoyed G - guilt E - eye opener
when are the PAT and FAST tools used
short screening tools for A&E that suggests if further assessment is required
alcohol inhibits which neurotransmitter
NMDA glutamate controlled ion channels
alcohol potentiates which ion channels
GABA controlled (inhibitory)
withdrawal from alcohol causes what change in neurotransmitters
causes excess glutamate activity which is neurotoxic and reduces GABA activity - causes CNS excitability
what are the clinical features of withdrawal
restless tremor sweating anxiety nausea/vomiting loss of appetite tachycardia generalised seizures
what a severe complication of alcohol withdrawal
delirium tremens
how does delirium tremens present
night time confusion disorientation agitation fever hallucinations paranoid ideation
how long does delirium tremens typically last
5-7 days
how is alcohol withdrawal managed
benzodiazepines - usually diazepam and gradually reduce dose over 7 days
parenteral vitamin supplementation (thiamine as prophylaxis)
what are the non-pharmacological methods for alcohol relapse prevention
CBT
Alcoholics Anonymous
family and couple therapy
once someone has come out of withdrawal, which drug is started and how does it work
naltrexone - opioid antagonist and reduces reward from alcohol
what is Antabuse
a medication used for alcohol detoxification, inhibits enzyme in breakdown causing flushed skin, tachycardia etc
alcohol excess can cause which deficiency
B1 - thiamine
thiamine deficiency can initially cause which syndrome
Wernicke’s encephalopathy
how does wernicke’s encephalopathy present
ataxia
confusion
double vision and ptosis
split into acute, acute-chronic and chronic
what is Korsakoff’s syndrome
chronic memory impairment associated with thiamine deficiency
what are the main features of Korsakoff’s syndrome
confabulations and anterograde amnesia
