FACEM Pharmacology Fundamentals 2

Question 1

Which pharmacokinetic parameter describes the fraction of an administered drug that reaches systemic circulation unchanged?

Accepted Answer

Bioavailability

Answer

Volume of distribution

Answer

Clearance

Answer

Half-life

Question 2

A patient with severe hepatic failure receives morphine. The most significant pharmacokinetic change expected is:

Accepted Answer

Reduced first-pass metabolism increasing bioavailability

Answer

Decreased volume of distribution

Answer

Accelerated renal clearance

Answer

Increased protein binding

Question 3

Which receptor type mediates the bronchodilatory effects of salbutamol?

Accepted Answer

Beta-2 adrenoceptor

Answer

Alpha-1 adrenoceptor

Answer

Beta-1 adrenoceptor

Answer

Muscarinic M3 receptor

Question 4

The concept of 'therapeutic index' is best defined as:

Accepted Answer

The ratio of the toxic dose to the effective dose (TD50/ED50)

Answer

The dose required for 50% of the population to respond

Answer

The maximum plasma concentration achieved after dosing

Answer

The time to reach steady-state concentration

Question 5

A competitive antagonist at the opioid receptor would be expected to:

Accepted Answer

Shift the agonist dose-response curve to the right with an unchanged maximum

Answer

Permanently block the receptor regardless of agonist concentration

Answer

Decrease the maximum response achievable by the agonist

Answer

Activate the receptor with lower intrinsic efficacy than the agonist

Question 6

Which enzyme is primarily responsible for the metabolism of succinylcholine in plasma?

Accepted Answer

Plasma cholinesterase (pseudocholinesterase)

Answer

Cytochrome P450 3A4

Answer

Monoamine oxidase

Answer

Glucuronyl transferase

Question 7

In a patient with end-stage renal failure, which analgesic metabolite accumulates and causes CNS toxicity including seizures?

Accepted Answer

Norpethidine (normeperidine)

Answer

Morphine-6-glucuronide

Answer

Fentanyl-N-oxide

Answer

Buprenorphine-3-glucuronide