KAPS Pharmacology Fundamentals 3

Question 1

A drug that blocks the effects of an agonist by binding to an allosteric site on the receptor (not the active site) is best described as:

Accepted Answer

Non-competitive antagonist

Answer

Non-competitive antagonists bind to allosteric sites, changing receptor conformation and reducing the maximal effect of the agonist regardless of agonist concentration.

Question 2

Which of the following best defines 'apparent volume of distribution' (Vd)?

Accepted Answer

A hypothetical volume in which a drug would need to be uniformly distributed to account for its plasma concentration

Answer

Vd is a theoretical volume that relates the total amount of drug in the body to the drug concentration measured in plasma.

Question 3

A patient taking Drug A (a CYP3A4 inhibitor) begins a new prescription for Drug B (a CYP3A4 substrate). What is the most likely outcome?

Accepted Answer

Increased plasma levels of Drug B

Answer

CYP3A4 inhibition reduces the metabolism of Drug B, causing it to accumulate and reach higher plasma concentrations.

Question 4

Which receptor superfamily uses a G-protein coupled mechanism where the activated receptor indirectly regulates ion channels or enzymes?

Accepted Answer

GPCRs (metabotropic receptors)

Answer

G-protein coupled receptors (GPCRs) are metabotropic receptors that activate intracellular G-proteins to modulate second messengers and downstream effectors.

Question 5

Renal clearance of a drug is reduced in a patient with kidney disease. What adjustment is typically required?

Accepted Answer

Decrease the dose or increase the dosing interval

Answer

Reduced renal clearance means the drug accumulates, so the dose should be reduced or the interval extended to avoid toxicity.

(KAPS) Knowledge Assessment of Pharmaceutical Sciences Practice Test

(KAPS) Knowledge Assessment of Pharmaceutical Sciences Practice Test

KAPS Pharmacology Fundamentals 3