Pharmacokinetics

Question 1

First order kinetics

Answer 1

Constant fraction of drug is removed per unit time

50% in 1st hour

50% in second hour

…

Looks linear on a log scale

Question 2

Zero order kinetics

Answer 2

Constant amount of drug removed/unit time

5mL hour 1

5mL hour 2

Looks linear on a linear scale

Question 3

Half life

Answer 3

Time it takes for conc in plasma to decrease by half

Question 4

Elimination constant

Answer 4

-dx/dt=Ke

It is the slope of the log curve

Question 5

Fundamental relationship of pharmacokinetics

Answer 5

.693=KeT_1/2

Question 6

What does the apparent volume of distribution tell us?

Answer 6

Can predict how much drug must be given to obtain a specific plasma conc of drug

Question 7

Clearance

Answer 7

Volume of fluid which is cleared of the drug in unit time

CL=Ke(Vd)

Question 8

After a single does how long does it take for the drug to be 99% eliminated

Answer 8

5-6 half lives

Question 9

Amount of drug in the body at steady state eq

Answer 9

(1.44*T_1/2*Dose)/Interval

Question 10

Concentration at steady state

Answer 10

(1.44*T1/2*Dose)/(Interval*Vd)

Question 11

Loading dose

Answer 11

Concentration at steady state*Vd=loading dose

Dose at which desired conc is acheived rapidly