GBP8

Question 1

How are water soluble drugs excreted

Answer 1

Liver or kidney

Question 2

How are lipid soluble drugs excreted

Answer 2

Metabolised by the liver gut or blood then made water soluble ready for excretion by liver or kidney

Question 3

How are volatile drugs excreted

Answer 3

Lungs

Question 4

What can be the biological consequences of drug metabolism

Answer 4

inactivation- phenytoin, warfarin, suxamethonium

activation- clopidogrel, dabigatran, paracetamol, halothene

Question 5

What is the toxic metabolite of paracetamol and what is it normally mopped up by

Answer 5

NAPQ1, mopped up by glutathine

Question 6

What are the two phases in metabolism

Answer 6

phase 1 - introduction or unmasking of functional group, some increase in water solubility
phase 2 - conjugation with endogenous chemical at functional centre, great increase in water solubilty

Question 7

What are oxidations done by in the liver

Answer 7

cytochrome p450

Question 8

Why is cyto.p450 important in the liver

Answer 8

has many isoforms due to genetic variation or because they are inducible

Question 9

How are alcohols oxidised in the liver

Answer 9

alcohol dehydrogenase

Question 10

How are amines oxidised

Answer 10

monoamine oxidase`

Question 11

What is beneficial about conjugation

Answer 11

makes the metabolite much more water soluble

Question 12

What types of conjugation are there

Answer 12

glucuronidation, sulphation, glycine conjugation, acetylation

Question 13

What is significant about age and metabolism

Answer 13

extreems of age both have reduced metabolism

Question 14

What interaction mechanisms exist

Answer 14

inhibition, induction