Applied Clinical Pharmacokinetics Exam Verified
Questions, Correct Answers, and Detailed
Explanations for Science Students||Already Graded
A+
1. Which of the following pharmacokinetic parameters is directly
proportional to the dose of a drug?
A) Half-life
B) Volume of distribution
C) Plasma concentration
D) Clearance
Rationale: Plasma concentration increases proportionally with dose assuming
linear pharmacokinetics, while clearance and half-life remain constant.
2. A patient has a creatinine clearance of 40 mL/min. Which drug would most
likely require dose adjustment?
A) Aminoglycosides
B) Lorazepam
C) Fentanyl
D) Diazepam
Rationale: Aminoglycosides are renally cleared, so impaired renal function
necessitates dose adjustment.
3. For a drug following first-order kinetics, which statement is true?
A) The rate of elimination is constant
B) The half-life changes with concentration
C) The rate of elimination is proportional to drug concentration
D) The drug accumulates exponentially without limit
Rationale: First-order kinetics means a constant fraction of drug is eliminated
per unit time, making the rate proportional to plasma concentration.
,4. The volume of distribution (Vd) is best described as:
A) Amount of drug excreted per hour
B) A theoretical volume that relates drug amount to plasma concentration
C) The fraction of drug absorbed
D) Plasma protein binding percentage
Rationale: Vd is a conceptual volume that indicates how extensively a drug
distributes into tissues.
5. A patient receiving a continuous IV infusion reaches steady state. The time
to reach steady state is primarily determined by:
A) Dose
B) Half-life
C) Clearance
D) Bioavailability
Rationale: Steady state is typically reached after ~4–5 half-lives, independent of
dose or infusion rate.
6. Which of the following drugs exhibits zero-order kinetics at therapeutic
concentrations?
A) Gentamicin
B) Phenytoin
C) Penicillin
D) Metformin
Rationale: Phenytoin is metabolized by saturable enzymes, so elimination
becomes constant (zero-order) at higher concentrations.
7. Which equation is used to calculate creatinine clearance in adults?
A) Henderson-Hasselbalch
B) Cockcroft-Gault
C) Michaelis-Menten
D) Nernst
Rationale: The Cockcroft-Gault equation estimates renal function for drug
dosing.
, 8. A drug has a Vd of 0.7 L/kg in a 70 kg patient. The total volume of
distribution is:
A) 35 L
B) 49 L
C) 49 L
D) 70 L
Rationale: Vd = 0.7 × 70 = 49 L.
9. Which factor increases the risk of drug accumulation?
A) High clearance
B) Long half-life
C) Low protein binding
D) Rapid metabolism
Rationale: Drugs with long half-lives remain in the body longer, increasing
accumulation risk.
10. The bioavailability of an IV drug is:
A) Less than 100%
B) Variable
C) 100%
D) Dependent on absorption
Rationale: IV administration bypasses absorption barriers, making
bioavailability complete.
11. A patient is on gentamicin. Peak concentration is 12 mcg/mL and trough
is 2 mcg/mL. What is the main goal of monitoring?
A) Adjust dose to prevent hypotension
B) Prevent nephrotoxicity and optimize efficacy
C) Ensure bioavailability
D) Reduce half-life
Rationale: Aminoglycoside monitoring prevents toxicity while maintaining
therapeutic levels.
Questions, Correct Answers, and Detailed
Explanations for Science Students||Already Graded
A+
1. Which of the following pharmacokinetic parameters is directly
proportional to the dose of a drug?
A) Half-life
B) Volume of distribution
C) Plasma concentration
D) Clearance
Rationale: Plasma concentration increases proportionally with dose assuming
linear pharmacokinetics, while clearance and half-life remain constant.
2. A patient has a creatinine clearance of 40 mL/min. Which drug would most
likely require dose adjustment?
A) Aminoglycosides
B) Lorazepam
C) Fentanyl
D) Diazepam
Rationale: Aminoglycosides are renally cleared, so impaired renal function
necessitates dose adjustment.
3. For a drug following first-order kinetics, which statement is true?
A) The rate of elimination is constant
B) The half-life changes with concentration
C) The rate of elimination is proportional to drug concentration
D) The drug accumulates exponentially without limit
Rationale: First-order kinetics means a constant fraction of drug is eliminated
per unit time, making the rate proportional to plasma concentration.
,4. The volume of distribution (Vd) is best described as:
A) Amount of drug excreted per hour
B) A theoretical volume that relates drug amount to plasma concentration
C) The fraction of drug absorbed
D) Plasma protein binding percentage
Rationale: Vd is a conceptual volume that indicates how extensively a drug
distributes into tissues.
5. A patient receiving a continuous IV infusion reaches steady state. The time
to reach steady state is primarily determined by:
A) Dose
B) Half-life
C) Clearance
D) Bioavailability
Rationale: Steady state is typically reached after ~4–5 half-lives, independent of
dose or infusion rate.
6. Which of the following drugs exhibits zero-order kinetics at therapeutic
concentrations?
A) Gentamicin
B) Phenytoin
C) Penicillin
D) Metformin
Rationale: Phenytoin is metabolized by saturable enzymes, so elimination
becomes constant (zero-order) at higher concentrations.
7. Which equation is used to calculate creatinine clearance in adults?
A) Henderson-Hasselbalch
B) Cockcroft-Gault
C) Michaelis-Menten
D) Nernst
Rationale: The Cockcroft-Gault equation estimates renal function for drug
dosing.
, 8. A drug has a Vd of 0.7 L/kg in a 70 kg patient. The total volume of
distribution is:
A) 35 L
B) 49 L
C) 49 L
D) 70 L
Rationale: Vd = 0.7 × 70 = 49 L.
9. Which factor increases the risk of drug accumulation?
A) High clearance
B) Long half-life
C) Low protein binding
D) Rapid metabolism
Rationale: Drugs with long half-lives remain in the body longer, increasing
accumulation risk.
10. The bioavailability of an IV drug is:
A) Less than 100%
B) Variable
C) 100%
D) Dependent on absorption
Rationale: IV administration bypasses absorption barriers, making
bioavailability complete.
11. A patient is on gentamicin. Peak concentration is 12 mcg/mL and trough
is 2 mcg/mL. What is the main goal of monitoring?
A) Adjust dose to prevent hypotension
B) Prevent nephrotoxicity and optimize efficacy
C) Ensure bioavailability
D) Reduce half-life
Rationale: Aminoglycoside monitoring prevents toxicity while maintaining
therapeutic levels.
