Drug Absorption #1

Question 1

biopharmaceutics deals with factors that influence….

Answer 1

bioavailability

Question 2

What factors can affect bioavailability? (4)

Answer 2

• drug
• patient specifically
• form
• route of administration

Question 3

T/F The amount of drug in the blood will effect the amount of drug that gets to the site of action.

Answer 3

TRUE

Question 4

Cmax

Answer 4

the highest concentration achievable from a single dose

Question 5

Tmax

Answer 5

how long from administrations before the maximum concentration is achieved

Question 6

Increased rate?–»

Answer 6

Cmax: Increase
Tmax: Decrease
AUC: no effected

Question 7

Increased extent?–>

Answer 7

Cmax: Increase
Tmax: no effect
AUC: Increase

Question 8

T/F Cmax and Tmax are usually visually determined

Answer 8

TRUE

Question 9

AUC is determined by using the …..

Answer 9

Trapezoidal rule–>

Area= 1/2 (a +b) * c (sum of the two parallel sides * distance between the sides * 1/2

Question 10

____ is determined using the last two concentration values collected

Answer 10

K el(Elimination constant)

Question 11

K el or elimination is ___ order, so you have to change it to ____

Answer 11

FIRST; log

Question 12

T/F Once the drug is released from the dosage form, it has to be dissolved before it can cross the membrane

Answer 12

TRUE

Question 13

By what mechanism are most drugs given orally absorbed?

Answer 13

passive diffusion

Question 14

Why do we have carriers in the GI tract?

Answer 14

to move nutrients through the membrane (these can not passively move across)

Question 15

Rate of diffusion (dc/dt) determines….

Answer 15

how slow or rapidly the drug moves into the blood

Question 16

P (3)

Answer 16

• partition coefficient
• measure of lipid solubility
• a constant

Question 17

A LARGER P = …..

Answer 17

Higher Lipid solubility

Question 18

Partition coefficient equation

Answer 18

ratio of relative solubility of a drug in lipid (/) relative solubility in water

Question 19

D

Answer 19

diffusion coefficient

-a constant

Question 20

A

Answer 20

area of surface at which diffusion is occurring

-a constant

Question 21

h

Answer 21

thickness of the membrane

-a constant

Question 22

C ad

Answer 22

concentration of drug at the site of administration

Question 23

C p

Answer 23

concentration of drug in the plasma

Question 24

T/F Diffusion is a random process

Answer 24

TRUE

Question 25

Drug diffusing into the blood after being administered is driven by

Answer 25

kinetic energy (random movement of molecules)

Question 26

Direction in which the molecules move depends on…..

Answer 26

the concentration gradient (usually from high to low concentration)

Question 27

Permeability depends on ____ and _____ properties

Answer 27

solute and membrane

Question 28

Drug Absorption is GENERALLY a _____ order process

Answer 28

FIRST

Question 29

Which law can be used to determine the rate of diffusion?

Answer 29

Fisk Law of Diffusion