Addiction + Alcohol Misuse Flashcards
UK Drinking guidelines
men + women 14 units a week with 2 alcohol free days a week
binge drinking for men
8 units
binge drinking for women
6 units
high risk drinking
regularly consuming >35 units a week
features of alcohol dependence syndrome
strong desire/compulsion to drink difficulty controlling use physiological withdrawal state evidence of tolerance persistence with use despite evidence of harm
how does alcohol effect the brain
inhibits action of excitatory NMDA glutamate controlled ion channels
potentiates inhibitory actions of GABA controlled ion channels
what does alcohol withdrawal leads to
excess glutamate activity – toxic to nerve cell
reduced GABA activity
effects of acute alcohol withdrawal in dependent individual
CNS excitability
neurotoxicity
symptoms of alcohol withdrawal
restlessness, tremor, sweating, anxiety, N+V, loss of appetite, insomnia, tachycardia, hypertension
onset of seizures / delirium tremens in alcohol withdrawal
seizures = 36 hours
delirium tremens = 72 hours
symptoms of delirium tremens
confusion agitation disorientation visual/ auditory hallucinations paranoid ideation
what do benzodiazepines act on
GABA A receptors
why is thiamine given in alcohol withdrawal
prophylaxis against wernicke’s encephalopathy
what is wernicke’s encephalopathy
haemorrhage into mammillary bodies due to thiamine deficiency
patient with alcohol dependence ‘staggering, confused + restricted eye movements’
wernicke’s encephalopathy
what is Korsakoff syndrome
patient acting strange, confabulating, short term memory problems
what is given for Korsakoff syndrome
pabrinex then thiamine
first line for alcohol dependence relapse prevention
naltrexone
mode of action of naltrexone
opioid antagonist
-reduces reward from alcohol
contraindications of naltrexone
cirrhosis or renal failure
other drugs used to preventi alcohol dependence relapse
disulfiram
- inhibits acetaldehyde dehydrogenase
acamprostate
- acts on glutamate + GABA systems to decrease cravings
what is the reward pathway
mesolimbic
what neurotransmitter is involved in addiction
dopamine
what part of the brain is the key creator of motivation to act
orbito-frontal cortex
role of pre-frontal cortex
modulates powerful effects of reward pathway
- keeps emotions + impulses under control
- makes sound decisions
how does drug abuse affect dopamine receptors
down regulates them - need more dopamine for same effect each time
opioid substitution therapies
methadone
buprenorphine
opioid overdose treatment
naloxone
