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

Bioavailability (F) is the fraction of administered drug that reaches systemic circulation unchanged, accounting for absorption and first-pass metabolism.

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

Severe hepatic failure impairs first-pass metabolism, dramatically increasing the oral bioavailability of drugs like morphine.

Question 3

Which receptor type mediates the bronchodilatory effects of salbutamol?

Accepted Answer

Beta-2 adrenoceptor

Answer

Salbutamol is a selective beta-2 adrenoceptor agonist that causes bronchial smooth muscle relaxation and bronchodilation.

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 therapeutic index is TD50/ED50; a narrow therapeutic index means toxic and therapeutic doses are close together, requiring careful monitoring.

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

Competitive antagonists shift the dose-response curve rightward (increasing ED50) but the maximum effect is preserved if enough agonist is present.

(FACEM) Fellowship of the Australasian College for Emergency Medicine Practice Test

(FACEM) Fellowship of the Australasian College for Emergency Medicine Practice Test

FACEM Pharmacology Fundamentals 2