Alcohol Flashcards
Name the 3 features of Ethanol (3)
Small
Weakly Charged
Readily Crosses BBB
What affects the pharmacokinetics of Alcohol (4)
Depends on gastric contents
Faster gastric emptying leads to faster absorption in the duodenum and therefore a peak alcohol concentration (slower is less damaging)
Concentration of Ethanol
Route of Administration
Distribution of Alcohol Use (3)
Male vs Female
Young vs Old
Protein Binding or Nah
Male
Young
No Protein Binding
Metabolism of Ethanol (3)
Oxidation by Alcohol Dehydrogenase in Liver and Stomach
Conjugation by Ethyl Glucoronide
Enzyme activity varies within populations (age, race, sex, BMI, enzyme mutation and liver disease)
Evolution of Alcohol Metabolism (1)
dealing with fermenting fruit and veg
Elimination of Ethanol (2)
1% unchanged in breath, sweat and urine
the rest is eliminated 7-10g (1 unit) per hour under zero order kinetics - no half life
Pharmacodynamics of Ethanol (4)
GABA - binds to GABAa receptors and mediates synaptic inhibition by opening Cl- channels
NMDA - inhibition of excitatory amino acid receptors
Effects - anxiolytic, sedating, anticonvulsant, amnesic, disinhibition, euphoria, loss of coordination
coma, respiratory depression and death
Complex due to rapid tolerance - tolerance is a diagnostic feature of dependence
What is the change in pharmacodynamics that occurs in alcohol use vs dependence? (2)
acute use causes dopamine release through the mesolimbic pathway activated by acetylaldehyde
chronic use causes downregulation of dopaminergic neurons and promotes an alcohol consumption to get a reward
Pharmacodynamics and symptoms of alcohol withdrawal (3)
Altered expression of GABA and NMDA receptors causing hyper excitability of the CNS
abrupt withdrawal can therefore lead to death
symptoms are anxiety, insomnia, sweating, tremor, vomiting and autonomic instability. As well as delerium tremens (hallucinations, fever, confusion) and seizures
Management of Alcohol withdrawal (2)
diazepam and chlorolazepoxide based on the level of tolerance (binds to GABA), reduce the dose gradually over 5-7 days
B12 and thiamine
Chronic alcohol use long term effects (2)
cerebral atrophy
direct damage to hippocampus, dentate granular levels and cerebellar vermis
What disorders can chronic alcohol use lead to? (12)
Freidrick’s Ataxia
Alcoholic Dementia
Wernicke-Korsikoff’s Syndrome (confusion, thiamine deficiency as its phosphorylated to TPP in glucose metabolism, and mammilary bodies which are symmetrical lesions around the 3rd ventricle)
Korsikoff’s - anterograde amnesia, marked widening of intratemporal tissue
Depression
Impaired Brain Development
Suicide
Hepatic Encephalopathy - personality changes, intellectual impairment, depressed consciousness, cirrhosis, porto-systemic shunts and amnesia in the brain
executive dysfunction
insomnia
cravings
delerium tremens
What disorder does skin folds in the corner of the eye, low nasal bridge, short nose, indistinct phillum, small head circumference, small eye opening, small midface, thin upper lip, growth restriction and cognitive and behavioural difficulties describe? (1)
Foetal Alcohol Syndrome
Mechanism of Foetal Alcohol Syndrome (3)
crosses the placenta, foetal liver has 10% function of mothers liver so there is direct damage to cell differentiation.
It inhibits the passage of amino acids, glucose, folic acid and zinc across the placenta
chronic foetal hypoxia
What are the two phases of alcohol dependence and what is used to treat them? (2)
Acute withdrawal
Relapse prevention (disulfiram, Naltrexone and Acamprostate)
