drug excretion

Question 1

where in the body is the drug prepared for elimination?

Answer 1

liver

Question 2

what are examples of phase 1 reactions?

Answer 2

oxidation, reduction, hydrolysis

Question 3

what are examples of phase 2 reactions?

Answer 3

conjugation

-glucuronidation, sulphation, methylation, acetylation

Question 4

where does the most extensive excretion occur?

Answer 4

renal excretion of water soluble metabolites-urine
liver metabolism and excretion-bile
lungs-inhales gases and volatile fractions of other drugs

Question 5

where are small portions of drugs excreted?

Answer 5

sweat
saliva
tears

Question 6

what diseases interfere with normal function of main excretory organs?

Answer 6

renal disease
-chronic renal failure
-drug doses must be reduced
liver disease
-liver failure
-drug doses must be reduced

Question 7

what is plasma half life?

Answer 7

time taken to eliminate half a drug

Question 8

what is first order kinetic?

Answer 8

drug metabolism increases as drug concentration increases

excretion by passive diffusion only

Question 9

what is zero order kinetics?

Answer 9

drug metabolism is at a fixed rate-active process
irrespective of drug concentration
can lead to the drug accumulation if saturation exceeded

Question 10

what will too frequent dosing lead to?

Answer 10

plasma levels that may be toxic

-depends on the drug’s therapeutic index

Question 11

what will too infrequent dosing lead to ?

Answer 11

sub-therapeutic plasma levels and no clinical effect