Drug Disposition

Question 1

Metabolism and excretion combined make what?

Answer 1

Elimination

Question 2

What is the primary organ of drug metabolism?

Answer 2

Liver

Question 3

Why must benzylpenicillin be given IV?

Answer 3

unstable in acidic environment of stomach

Question 4

Why must insulin be given subcutaneously?

Answer 4

As a peptide, it will be degraded by acidic environment in stomach

Question 5

By what calculation can properties of ionised and unionised drugs be calculated?

Answer 5

Henderson-Hasselbalch

Question 6

Do acidic drugs become more or less ionised in acidic environment?

Answer 6

Less

Question 7

What facilitates absorption of weak acids?

Answer 7

stomach lumen

Question 8

Where does the majority of absorption occur?

Answer 8

small intestine

Question 9

What is the pH in the duodenum?

Answer 9

neutral

Question 10

What is the pH in the jejenum and ileum?

Answer 10

slightly alkaline

Question 11

Drugs administered through what method have 100& systemic availability?

Answer 11

IV

Question 12

What route of drug entry involves first pass metabolism?

Answer 12

Oral

Question 13

What route of drug entry is used for nocturnal administration of some drugs?

Answer 13

Rectal

Question 14

What route of drug entry has rapid onset and needs sterile preparation?

Answer 14

IV

Question 15

What route of drug has rapid onset of lipid soluble drugs in particular?

Answer 15

Subcutaenous

Question 16

Which drug routes are ideal for localised effect?

Answer 16

Topical, inhalational

Question 17

Which drug route method is hardly ever used as it is associated with some dangerous effects?

Answer 17

Intra-arterial

Question 18

What drug route is good for volatile agents?

Answer 18

Inhalational

Question 19

Are bound drug molecules able to move between compartments?

Answer 19

No, only free drug molecules can

Question 20

Can ionised drugs move readily by diffusion?

Answer 20

No, only unionised drugs can

Question 21

Are drugs evenly distributed in the body?

Answer 21

No

Question 22

What does a volume of distribution under 5L imply?

Answer 22

drug is retained in vascular compartment

Question 23

What does a volume of distribution under 15L imply?

Answer 23

Drug retained to extracellular water

Question 24

What does a volume of distribution of more than 15L imply?

Answer 24

Distribution is throughout total body water