Pharmacy Pharmacokinetics 1

Question 1

What does 'bioavailability' refer to in pharmacokinetics?

Accepted Answer

The fraction of an administered dose that reaches systemic circulation unchanged

Answer

The rate at which a drug is metabolized by the liver

Answer

The volume of plasma cleared of drug per unit time

Answer

The time required for drug concentration to decrease by half

Question 2

Which route of administration achieves 100% bioavailability?

Accepted Answer

Intravenous

Answer

Oral

Answer

Sublingual

Answer

Transdermal

Question 3

The 'first-pass effect' primarily occurs in which organ?

Accepted Answer

Liver

Answer

Kidney

Answer

Lung

Answer

Small intestine only

Question 4

Volume of distribution (Vd) is best defined as:

Accepted Answer

The theoretical volume needed to contain all drug at the observed plasma concentration

Answer

The actual blood volume in the body

Answer

The volume of urine produced per hour

Answer

The volume of drug eliminated per unit time

Question 5

A drug with a high volume of distribution (Vd > 20 L/kg) is most likely:

Accepted Answer

Extensively distributed to peripheral tissues

Answer

Confined primarily to the plasma compartment

Answer

Highly protein-bound to albumin in plasma

Answer

Rapidly eliminated by the kidneys

Question 6

Which pharmacokinetic parameter describes the rate of drug elimination relative to drug concentration in plasma?

Accepted Answer

Clearance

Answer

Half-life

Answer

Volume of distribution

Answer

Bioavailability

Question 7

The elimination half-life (t½) of a drug is mathematically related to which two pharmacokinetic parameters?

Accepted Answer

Volume of distribution and clearance

Answer

Bioavailability and protein binding

Answer

Absorption rate constant and distribution rate

Answer

Renal clearance and hepatic clearance only