drug absorption

Question 1

there is always a correlation between plasma concentration of a drug and

Answer 1

the therapeutic response

Question 2

The time to peak concentration

Answer 2

Tmax

Question 3

The peak concentration

Answer 3

Cmax

Question 4

The area under the drug concentration curve

Answer 4

AUC

Question 5

Tmax

Answer 5

The more rapid the rate of absorption, the earlier the drug concentration peak

Question 6

Cmax

Answer 6

Increasing the dose doesn’t affect the time at which peak concentration is reached but it does increase the peak concentration

Question 7

AUC

Answer 7

The area under the drug-concentration time curve represents the amount of drug which reaches the systemic circulation

Question 8

Therapeutic range

Answer 8

A drug that is active over a range of concentrations

Question 9

Below therapeutic range

Answer 9

no pharmacological action

Question 10

Above therapeutic range

Answer 10

toxicity occurs

Question 11

AUC

Answer 11

allows for estimating the amount of drug which reaches the circulation and which is available for action

BIOAVAILABILITY

Question 12

Factors effecting bioavailability

Answer 12

Formulation (slow release)

Ability of drug to pass physiological barriers

Gastrointestinal effects

First pass metabolism

Question 13

Most drugs do not completely ionise in

Answer 13

water

Question 14

The degree of ionisation depends on the

Answer 14

pH of the environment

Question 15

Henderson-hasselbach equation

Answer 15

relationship between local pH and the degree of ionisation

results: small changes in pH may significantly influence the ionisation of a drug and therefore the rate of absorption or diffusion

Question 16

Lipid solubility

Answer 16

ability of a drug to pass a lipid layer

Question 17

Lipid-water partition coefficient

Answer 17

the ability of a drug to diffuse across a lipid barrier

ratio of the amount of drug which dissolved in the lipid and water phase when they are in contact

Question 18

Passive Diffusion

Answer 18

Very common

occurs along a concentration gradient

Question 19

Active absorption

Answer 19

unusual

occurs AGAINST a concentration gradient

requires carrier and energy

Question 20

Facilitative diffusion

Answer 20

occurs along the concentration gradient

requires carriers

NO ENERGY needed

Question 21

Gastrointestinal Factors

Answer 21

Motility (speed of gastric absorption will effect speed at which drug reaches site of absorption)

Food

Illness (malabsorption - eg celiac disease)

Question 22

First Pass Metabolism

Answer 22

metabolism of drug prior to reaching systemic circulation