Pharmacokinetics: Master Drug Movement in the Body for Pharmacy Success

Question 1

Which of the following factors **does not** influence the volume of distribution of a drug?

Accepted Answer

pH of tissues

Answer

Protein binding

Answer

Lipophilicity

Answer

Molecular size

Question 2

The volume of distribution (Vd) represents:

Accepted Answer

The total amount of drug in the body

Answer

The extent of drug binding to plasma proteins

Answer

The concentration of drug in the plasma

Answer

The rate of drug elimination

Question 3

Which of the following methods can be used to estimate drug clearance?

Accepted Answer

Both of the above

Answer

Using the formula: Clearance = (Dose / AUC)

Answer

Plotting a semi-logarithmic graph of drug concentration over time

Question 4

The volume of distribution (Vd) provides an estimate of:

Accepted Answer

The amount of drug in the body

Answer

The concentration of drug in the body

Answer

The amount of drug in the central compartment

Answer

The concentration of drug in the peripheral compartment

Question 5

The elimination half-life of a drug represents:

Accepted Answer

The time required for the drug concentration to decrease by 50%

Answer

The time required for the drug concentration to increase by 50%

Answer

The time for complete elimination of the drug from the body

Answer

The time for the drug to reach steady state

Question 6

Bioavailability refers to:

Accepted Answer

The fraction of drug that reaches the systemic circulation

Answer

The rate of drug absorption

Answer

The concentration of drug in the blood

Answer

The time to reach peak drug concentration

Question 7

A drug with a volume of distribution of 3 L has a plasma concentration of 10 mg/L. What is the total amount of drug in the body?

Accepted Answer

30 mg (correct)

Answer

10 mg

Answer

100 mg

Answer

300 mg

Question 8

A drug has a half-life of 4 hours. How much time will it take for the drug concentration to decrease to 6.25% of its initial value?

Accepted Answer

8 hours (correct)

Answer

4 hours

Answer

16 hours

Answer

24 hours

Question 9

A patient is taking a drug that is extensively bound to plasma proteins. What is the expected impact of this binding?

Accepted Answer

Increased drug distribution (correct)

Answer

Decreased drug distribution

Answer

No change in drug distribution

Answer

Increased drug elimination

Question 10

A drug has a clearance of 5 L/min and a volume of distribution of 20 L. What is the elimination rate constant (k)?

Accepted Answer

0.025 min^-1 (correct)

Answer

0.25 min^-1

Answer

2.5 min^-1

Answer

25 min^-1

Question 11

Which of the following is a non-compartmental pharmacokinetic model used to describe drug disposition?

Accepted Answer

One-compartment model (correct)

Answer

Two-compartment model

Answer

Mammillary model

Answer

Physiologically-based pharmacokinetic model

Question 12

A patient has a creatinine clearance of 60 mL/min. What is their estimated glomerular filtration rate (GFR)?

Accepted Answer

120 mL/min (correct)

Answer

60 mL/min

Answer

180 mL/min

Answer

240 mL/min

Question 13

Which of the following is NOT a recognized route of drug administration?

Accepted Answer

Intraocular

Answer

Oral

Answer

Inhalation

Answer

Transdermal

Question 14

Which of the following factors does NOT influence the rate of drug absorption?

Accepted Answer

Patient's age

Answer

Dosage form

Answer

Surface area of absorption

Answer

Blood flow to absorption site

Question 15

The apparent volume of distribution (Vd) of a drug represents:

Accepted Answer

Volume of body water into which the drug is distributed

Answer

Total amount of the drug in the body

Answer

Extent of drug binding to plasma proteins

Answer

Rate of drug elimination

Question 16

Which of the following enzymes is primarily responsible for Phase I drug metabolism reactions?

Accepted Answer

Cytochrome P450

Answer

UDP-glucuronosyltransferases

Answer

Sulfotransferases

Answer

Acetyltransferases

Question 17

The process by which a drug is eliminated from the body without undergoing changes is known as:

Accepted Answer

Renal excretion

Answer

Hepatic metabolism

Answer

Biliary excretion

Answer

Pulmonary excretion

Question 18

Which of the following is a mechanism of drug absorption?

Accepted Answer

Carrier-mediated transport

Answer

Pinocytosis

Answer

Passive diffusion

Answer

Renal excretion

Question 19

The term 'bioavailability' refers to:

Accepted Answer

The fraction of an administered drug that reaches the systemic circulation unchanged

Answer

The volume of distribution of a drug

Answer

The rate at which a drug is absorbed into the body

Question 20

A drug with a large volume of distribution will:

Accepted Answer

Have a longer half-life and distribute more extensively into tissues

Answer

Have a larger clearance

Answer

Be more lipophilic

Answer

Be less likely to accumulate in tissues

Question 21

The hepatic first-pass effect:

Accepted Answer

Reduces the bioavailability of orally administered drugs by metabolizing them before they reach the systemic circulation

Answer

Enhances the therapeutic efficacy of drugs

Answer

Increases the duration of action of drugs

Question 22

The half-life of a drug refers to the:

Accepted Answer

Time taken for the drug concentration in the body to decrease by 50%

Answer

Time taken for the drug to be completely eliminated from the body

Answer

Time taken for the drug to reach its peak concentration

Question 23

Drug interactions can occur at which of the following sites?

Accepted Answer

Multiple sites, including the absorption, distribution, metabolism, and excretion of drugs

Answer

The metabolism site only

Answer

The absorption site only