Lecture 1 - Definitions etc

Question 1

what is an alcohol?

Answer 1

organic liquid with a hydroxyl group on the end

Question 2

name 4 alcohols

which type is commonly in drinks?

Answer 2

methanol
ethanol - in drinks
propanol
butanol

Question 3

how does methanol poisoning come about and what does it cause?

Answer 3

in anti-freeze, dodgy home brewing etc

metabolised to formaldehyde then formic acid causing blindness and renal failure

Question 4

how is methanol poisoning treated? how does this work?

Answer 4

alcohol +/- dialysis
ethanol and methanol both metabolised by alcohol dehydrogenase so ethanol causes competitive inhibtion of the enzyme and formic acid cant be formed

Question 5

weekly unit limit?

Answer 5

14

spaced over few days

Question 6

symptoms of alcohol withdrawal?

Answer 6

“seeing spiders”

suddenly unwell during hospital stay or coming round from anaesthetic

Question 7

how is alcohol absorbed and what can affect the rate?

Answer 7

limited amount in stomach, most absorbed in small bowel
eating slows gastric emptying so slower absorption
antihistamines and metoclopramide increase emptying so faster absorption

Question 8

why is drinking on an empty stomach bad?

Answer 8

faster gastric emptying so faster absorption without being metabolised in the stomach first

Question 9

do men handle alcohol better than women?

Answer 9

generally yes
men have higher lean body mass % than women of same weight so more fluid to dilute the alcohol
women often have lower alcohol dehydrogenase levels

Question 10

which is absorbed quicker, spirits or aerated drinks (prosecco)?

Answer 10

aerated

spirits irritate gastric mucosa so slow emptying causing delayed effect (can hit you suddenly)

Question 11

do some ethnic groups handle alcohol better?

Answer 11

yes
some have little/no/ineffective alcohol dehydrogenase (Asians, aborigines, eskimos)
causes flushing, nausea, headaches etc

Question 12

how is alcohol metabolised?

Answer 12

alcohol > acetaldehyde (causes hangover)(alcohol dehydrogenase)
acetaldehyde > acetate (aldehyde dehydrogenase)
acetate > CO2 and H2O
90% in liver, some in brain/pancreas

Question 13

at what rate is alcohol removed from blood?

Answer 13

15mg/100ml/hr (1 unit per hr)

Question 14

when does alcohol conc peak?

Answer 14

60 mins after consumption

Question 15

how is alcohol tolerance achieved?

Answer 15

alcohol dehydrogenase upregulated via activation of alternative pathways in heavy drinking, e.g:

• MEOS
• catalase
• induction of CP450

Question 16

what are some consequences of alternative pathways?

Answer 16

inhibition of krebs cycle = anaerobic pathway = lactic acid (sore legs)
inhibits gluconeogenesis/glucogenolysis = use fats/proteins as substrates so get the munchies
impairs fatty acid oxidation = excess keogenesis and lipid synthesis (makes you fat)

Question 17

how does alcoholic ketoacidosis occur?

Answer 17

consequence of other pathways so you make ketones

Question 18

what is alcoholic ketoacidosis associated with?

Answer 18

malnourished chronic alcoholics

Question 19

what is the difference between alcoholic and diabetic ketoacidosis?

Answer 19

alcoholic = low/normal glucose, high ketones
diabetic = high glucose, high ketones

Question 20

how does alcohol supress the CNS?

Answer 20

increases GABBA levels which inhibits neurotransmitters

Question 21

where does alcohol effect and what does this affect?

Answer 21

cortex - disinhibition
limbic system - memory, confusion etc
cerebellum - coordination, balance, speech
reticular formation - consciousness (less stimulated = sleepy)
lower brain stem (breathing, BP, gag reflex)

Question 22

what do different levels of alcohol do?

Answer 22

<100 = cortex
100-200 = limbic system, cerebellum
>200 (stupor) = reticular formation, lower brain stem

Question 23

why does alcohol make you pee more?

Answer 23

drink more volume

directly inhibits ADH so reduced water reabsorption

Question 24

what causes a heavy heartbeat after drinking?

Answer 24

alcohol is a negative inotrope (reduces force of contraction > SV decreases > HR increases)

Question 25

what is holiday heart syndrome?

Answer 25

supraventricular tachycardia assoc with binge drinking

spontaneous resoluation

Question 26

what causes headache (veisalgia cephalgia) after drinking?

Answer 26

congeners in alcohols
serotonins in sulphites, tannins and phenols in red wine
mainly dehydration

Question 27

what is the key to curing a hangover?

Answer 27

inhibiting prostaglandins

Question 28

is there any health benefit to drinking a small amount (e.g half glass red wine every night)?

Answer 28

no

might not be bad but not good either