MPharm Master of Pharmacy Master of Pharmacy: Pharmacokinetics and Pharmacodynamics 2

Question 1

A drug with a volume of distribution of 700 L in a 70 kg patient is best described as:

Accepted Answer

Extensively distributed into tissues

Answer

A Vd of 700 L far exceeds total body water (~42 L), indicating extensive tissue distribution and sequestration.

Question 2

Which pharmacokinetic parameter directly determines the dosing interval needed to maintain steady-state concentrations within a therapeutic window?

Accepted Answer

Half-life

Answer

The elimination half-life governs how quickly drug levels decline, which directly informs appropriate dosing intervals.

Question 3

During a constant-rate IV infusion, steady-state is achieved when:

Accepted Answer

The rate of infusion equals the rate of elimination

Answer

Steady-state occurs when the rate of drug input equals the rate of drug elimination, resulting in constant plasma concentrations.

Question 4

A competitive antagonist shifts the agonist concentration-response curve:

Accepted Answer

To the right with an unchanged maximum response

Answer

Competitive antagonists shift the curve to the right (higher EC50) but the maximum effect can still be achieved with enough agonist.

Question 5

Which of the following best describes the concept of intrinsic efficacy in pharmacodynamics?

Accepted Answer

The ability of a drug-receptor complex to produce a biological response

Answer

Intrinsic efficacy describes the capacity of the drug-receptor complex to activate the receptor and produce a functional response.

MPharm Master of Pharmacy Practice Test