Pharmacokinetics

Question 1

what are the 5 important Rs in pharmacology

Answer 1

• right drug
• Right person
• Right dose
• right route
• right time

Question 2

what does pharmacokinetics talk about

Answer 2

it talks about the time in which a drug and its metabolites pass through the body and also accounts for the Absorption, Metabolism, Distribution and Excretion of the drug.

Question 3

which route of drug administration gives you a max concentration at T0 on the Drug Concentration time-curve

Answer 3

IV

Question 4

what is clearance and how is it calculated

Answer 4

it is the measure of the ability of the body to eliminate a drug,

clearance = rate of elimination/ plasma concentration of drug

Question 5

what is volume of distribution

Answer 5

it is the measure of the amount of space in the body that is available to contain the drug based on how much is given vs what is found in the systemic circulation and is measured as Amount of drug in body/ plasma Concentration

the larger the volume of distribution the more likely the drug is found in tissues of the body.

Question 6

what is half life

Answer 6

the time it takes for body to reduce the drug concentration by half.

Question 7

what is therapeutic index

Answer 7

it is the ratio between toxic dose and therapeutic dose.

the small the therapeutic index the greater risk for toxicity.

Question 8

steady state concentration

Answer 8

a phenomenon that talk to the idea that in order for a drug to maintain a target Concentration peak, it needs to be administered at a rate equal to the rate of elimination at that concentration.

Question 9

which type of drugs reach steady state faster

Answer 9

drugs with a longer half life.

Question 10

which two ways can absorption of a drug occur

Answer 10

through active diffusion and passive diffusion

the difference between the two is having to use energy for molecules to pass through channels

Question 11

name three active transporters

Answer 11

ABC (ATP Binding Cassette.)
P- glycoprotein
MDR-1(multidrug resistance 1)

Question 12

what improtant enzyme does P-glycoprotein work with

Answer 12

cytochrome P34A

Question 13

what two ways can saturable metabolism occur (Elimination Kinetics)

Answer 13

• zero order elimination kinetics
• first order elimination

Question 14

what does induction mean

Answer 14

switching on a gene regulator that increases the expression of many enzymes and this takes a minimum of 2 weeks to be effective and 2 weeks to wane

Question 15

what are the three routes that play a role in drug elimination in the kidneys

Answer 15

• glomerular filtration
• passive tubular reabsorption
• active tubular secretion

Question 16

what is the formula for excretion

Answer 16

filtration - reabsorption + secretion