Pharmacokinetics 2

Question 1

Active drug →inactive drug

Answer 1

ibuprofen, lidocaine, propranolol

Question 2

Active drug> active metabolites

Answer 2

Codeine > Morphine

primidone> Phenobarbitone

Question 3

Inactive drug (prodrugs) → active drug .

Answer 3

Enalapril > enalaprilat

prednisone > prednisolone

Question 4

Active drug → toxic metabolite

Answer 4

paracetamol→ N-acetyl–p-benzoquinone imine (5%)

Question 5

Monoamine oxidases inactivate active amines like:

Answer 5

tyramine,
noradrenaline
5-HT

Question 6

Site of metabolism of suxamethonium

Answer 6

Plasma via plasma cholinesterases

Question 7

Site of metabolism of some prostanoids (PGE2; PGE1; PGF2a)

Answer 7

Lung

Question 8

Site of metabolism of tyramine; salbutamol

Answer 8

Gut

Question 9

Example of “enzyme inhibition”

Answer 9

fluconazole + fluoxetine

Question 10

Examples of enzyme inhibitors:

Answer 10

Cimetidine, Erythromycin, Ketoconazole

Question 11

Example of enzyme induction:

Answer 11

Phenobarbitone, Phenytoin, Rifampicin.

Question 12

Herb-drug interactions e.g. (1) ———— induces (2) ————- which also metabolize (3) —————

Answer 12

(1) St John’s Wort
(2) CYP3A
(3) estradiol; sildenafil; simvastatin….

Question 13

Isoniazid, hydralazine
and procainamide are metabolized in a phase II
reaction by:

Answer 13

N-acetylation