Acute Alcohol Intoxication Flashcards
What is methanol found in?
Anti-freeze, solvents and some home brews
What is methanol metabolised to ?
Formaldehyde then formic acid
What can methanol acidosis lead to?
Blindness
Why is methanol poisoning treated with alcohol?
Competitive inhibition-both are metabolised by alcohol dehydrogenase
How many units of alcohol cause the liver to become fatty?
6 units
Where is alcohol mainly absorbed?
Small intestines
Why does a full stomach slow the effects of alcohol?
A full stomach slows gastric emptying which means more alcohol is metabolised in the stomach before moving into the small intestines
Give examples of substances that increase gastric emptying?
Anti-histamines and metoclopramide
Why are spirits and other drinks with high alcohol contents absorbed slower?
Spirits irritate the gastric mucosa and delay emptying
What percentage of alcohol has the quickest absorption?
20-30% (e.g sherry)
Why are women more affected by alcohol than men?
Women have a higher mass of subcutaneous fat percentage and a lower pool for dilution; women also have lower levels of alcohol dehydrogenase
What enzyme metabolises alcohol to acetaldehyde?
Alcohol dehydrogenase
What enzyme metabolises acetaldehyde to acetate?
Aldehyde dehydrogenase
What are the final products of alcohol metabolism?
CO2 and H2O
Where does alcohol metabolism take place?
90% occurs in liver; small volume in pancreas and breath
How much alcohol is excreted through the breath?
5%
What rate is alcohol removed from the blood?
15mg/100ml/hr (roughly 1 unit/hr)
After how long does alcohol concentration peak?
Around 60 mins after consumption
Name some ethnicities that have low/absent levels of alcohol dehydrogenase (or aldehyde dehydrogenase)
Aboriginies, Eskimos, Inuits
What percentage of Japanese people lack alcohol dehydrogenase?
50%
Why do SE Asians experience “Asian flushing”?
They have a deficient/ineffective variant of aldehyde dehydrogenase so acetaldehyde is not metabolised properly
What is Antabuse?
A drug that inhibits aldehyde dehydrogenase which makes drinking unpleasant
Name two alternative pathways utilised by heavy drinkers
MEOS pathway and Catalase pathway
What are the dangers of the MEOS pathway?
It produces hydrogen ions which inhibits hepatic gluconeogenesis, the Krebs cycle and fatty acid oxidation
What happens when the Krebs cycle is inhibited?
Switches to anaerobic metabolism so more likely to produce lactic acid
What happens when hepatic gluconeogenesis is inhibited?
Blood glucose becomes low
What happens when fatty acid oxidation is inhibited?
Excess ketogenesis and lipid synthesis
What state is alcoholic ketoacidosis associated with?
Malnourished state
What happens in alcoholic ketoacidosis?
Excess NADH and impaired fatty acid metabolism so fasting state results
What are the glucose levels like in alcoholic ketoacidosis?
Low or normal glucose with high ketones (usually beta-hydroxybutyrate)
What effect does alcohol have on the CNS?
CNS depressant-increases levels of GABBA
What is GABBA?
An inhibitor of neurotransmitters
What effects does alcohol have on the cortex?
Disinhibition, anxiolytic, talkativeness
What effects does alcohol have on the limbic system?
Memory loss, confusion
What effects does alcohol have on the cerebellum?
Loss of muscular co-ordination
What does the reticular formation of the brain control?
Consciousness
What is the lower brain stem involved in?
Control of breathing
What are the effects of alcohol levels <100?
Excitement, fun, still in control
What are the effects of alcohol levels between 100-200?
Slurring, blurred vision, falling over
What are the effects of alcohol levels >200?
Stupor, loud snoring, difficult to rouse
What does ADH do?
Promotes water reabsorption in the distal tubule of the kidneys and concentrates urine
What does alcohol do to ADH?
Directly inhibits it so reduces water reabsorption and dilutes urine (makes you pee more)
Why does alcohol give the sensation of a heavy heart beat?
Alcohol is a negative inotrope (reduces contractility)-heart has to beat faster to maintain CO
What are some features of holiday heart syndrome?
Linked with binge drinking, otherwise healthy heart, supraventricular tachycardia, spontaneous resolution
What is the headache of a hangover known as?
Veisalgia Cephalia
What are congeners?
Things added to contribute to the smell of alcohol
What substance that contributes to a headache are found in red wine?
Serotonin (produced from sulphites, tannins and phenols)
Which fruits can make a headache worse?
Bananas and pineapples
How could you cure a hangover?
Inhibit prostaglandins and speed up metabolism
