FPGEE Pharmacokinetics 3

Question 1

A drug undergoes saturable (Michaelis-Menten) hepatic metabolism. Which clinical consequence is most expected when the dose is increased from 200 mg to 300 mg?

Accepted Answer

Disproportionately large increase in plasma concentration

Answer

Near saturation, small dose increases cause disproportionately large rises in plasma concentration because elimination capacity is overwhelmed.

Question 2

For a two-compartment model, the initial rapid decline in plasma concentration after IV bolus primarily represents which process?

Accepted Answer

Distribution into peripheral tissues (alpha phase)

Answer

The alpha (distribution) phase reflects rapid drug transfer from central compartment (plasma) into peripheral tissue compartments.

Question 3

Which equation correctly relates clearance (CL), volume of distribution (Vd), and half-life (t½)?

Accepted Answer

t½ = 0.693 × Vd / CL

Answer

The correct relationship is t½ = 0.693 × Vd / CL, derived from first-order elimination kinetics.

Question 4

A drug has 95% plasma protein binding. Which statement about free (unbound) drug is most accurate?

Accepted Answer

Free drug is the pharmacologically active fraction

Answer

Only free (unbound) drug can cross membranes, interact with receptors, and be pharmacologically active or eliminated.

Question 5

A loading dose is calculated primarily based on which pharmacokinetic parameter?

Accepted Answer

Volume of distribution

Answer

Loading dose = Target Cp × Vd / F; volume of distribution determines how much drug is needed to achieve the desired plasma concentration immediately.

FPGEE Exam Practice Test

FPGEE Exam Practice Test

FPGEE Pharmacokinetics 3