PHARMACOLOGY FUNDAMENTALS EXAM
QUESTIONS AND CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2026
Section 1: Pharmacokinetics (Questions 1–35)
1. Which of the following best defines pharmacokinetics?
• A) The study of drug effects on the body
• B) The study of drug absorption, distribution, metabolism, and excretion
• C) The study of drug-receptor interactions
• D) The study of adverse drug reactions
Answer: B
Rationale: Pharmacokinetics describes what the body does to a drug (ADME).
Pharmacodynamics (A, C) describes what the drug does to the body.
2. A drug given intravenously has 100% bioavailability because:
• A) It bypasses first-pass metabolism
• B) It is metabolized in the liver
• C) It is excreted unchanged
• D) It binds to plasma proteins
Answer: A
*Rationale: IV administration delivers the drug directly into systemic circulation,
bypassing absorption barriers and first-pass hepatic metabolism, resulting in 100%
bioavailability.*
,3. A patient takes a drug that undergoes extensive first-pass metabolism. Which
route of administration would most effectively bypass this effect?
• A) Oral
• B) Sublingual
• C) Intramuscular
• D) Both B and C
Answer: D
Rationale: Sublingual (absorbed directly into systemic circulation via oral mucosa)
and intramuscular (into muscle, then systemic) both bypass the portal circulation
and first-pass hepatic metabolism.
4. The volume of distribution (Vd) of a drug is 500 L. This suggests that the drug:
• A) Is confined to the plasma
• B) Is extensively bound to plasma proteins
• C) Is extensively distributed into tissues
• D) Has poor tissue penetration
Answer: C
*Rationale: A very large Vd (>42 L for a 70 kg person) indicates extensive tissue
distribution (e.g., lipophilic drugs). A small Vd (~3-5 L) suggests confinement to
plasma (e.g., large molecules, high protein binding).*
5. Which of the following factors increases the volume of distribution of a drug?
• A) High plasma protein binding
• B) High lipophilicity
, • C) High molecular weight
• D) High polarity
Answer: B
Rationale: Lipophilic drugs cross cell membranes easily, distributing into adipose
tissue and other compartments, increasing Vd. High protein binding (A) tends to
keep drug in plasma (lower Vd).
6. A drug has a half-life of 4 hours. Approximately how many hours will it take to
reach steady state?
• A) 4 hours
• B) 8 hours
• C) 20 hours
• D) 40 hours
Answer: C
*Rationale: Steady state is achieved after approximately 5 half-lives (4 hours × 5 =
20 hours). At 1 half-life, 50%; 2 half-lives, 75%; 3 half-lives, 87.5%; 4 half-lives,
93.75%; 5 half-lives, 96.875%.*
7. A drug follows first-order elimination kinetics. Which statement is correct?
• A) A constant amount of drug is eliminated per unit time
• B) A constant fraction of drug is eliminated per unit time
• C) Elimination rate is independent of drug concentration
• D) Zero-order kinetics describes most drugs
Answer: B
*Rationale: First-order kinetics: constant fraction (e.g., 50% per hour) eliminated,
, half-life constant, elimination rate proportional to concentration. A describes zero-
order kinetics.*
8. A patient with alcohol intoxication has a blood alcohol level of 200 mg/dL. The
rate of elimination is constant regardless of concentration. This is an example of:
• A) First-order kinetics
• B) Zero-order kinetics
• C) Michaelis-Menten kinetics (saturable)
• D) Second-order kinetics
Answer: B
*Rationale: Ethanol elimination follows zero-order kinetics at therapeutic/toxic
levels because the enzyme (alcohol dehydrogenase) is saturated. A constant
amount (e.g., 15-20 mg/dL/hour) is eliminated.*
9. Which of the following is the major site of drug metabolism?
• A) Kidney
• B) Liver
• C) Lungs
• D) Intestine
Answer: B
*Rationale: The liver contains most drug-metabolizing enzymes (cytochrome P450
family, phase II conjugating enzymes). The kidney (A) primarily excretes drugs; gut
(D) and lungs (C) contribute less.*
10. A patient is a poor metabolizer of codeine (CYP2D6 substrate). Which of the
following is most likely?
QUESTIONS AND CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2026
Section 1: Pharmacokinetics (Questions 1–35)
1. Which of the following best defines pharmacokinetics?
• A) The study of drug effects on the body
• B) The study of drug absorption, distribution, metabolism, and excretion
• C) The study of drug-receptor interactions
• D) The study of adverse drug reactions
Answer: B
Rationale: Pharmacokinetics describes what the body does to a drug (ADME).
Pharmacodynamics (A, C) describes what the drug does to the body.
2. A drug given intravenously has 100% bioavailability because:
• A) It bypasses first-pass metabolism
• B) It is metabolized in the liver
• C) It is excreted unchanged
• D) It binds to plasma proteins
Answer: A
*Rationale: IV administration delivers the drug directly into systemic circulation,
bypassing absorption barriers and first-pass hepatic metabolism, resulting in 100%
bioavailability.*
,3. A patient takes a drug that undergoes extensive first-pass metabolism. Which
route of administration would most effectively bypass this effect?
• A) Oral
• B) Sublingual
• C) Intramuscular
• D) Both B and C
Answer: D
Rationale: Sublingual (absorbed directly into systemic circulation via oral mucosa)
and intramuscular (into muscle, then systemic) both bypass the portal circulation
and first-pass hepatic metabolism.
4. The volume of distribution (Vd) of a drug is 500 L. This suggests that the drug:
• A) Is confined to the plasma
• B) Is extensively bound to plasma proteins
• C) Is extensively distributed into tissues
• D) Has poor tissue penetration
Answer: C
*Rationale: A very large Vd (>42 L for a 70 kg person) indicates extensive tissue
distribution (e.g., lipophilic drugs). A small Vd (~3-5 L) suggests confinement to
plasma (e.g., large molecules, high protein binding).*
5. Which of the following factors increases the volume of distribution of a drug?
• A) High plasma protein binding
• B) High lipophilicity
, • C) High molecular weight
• D) High polarity
Answer: B
Rationale: Lipophilic drugs cross cell membranes easily, distributing into adipose
tissue and other compartments, increasing Vd. High protein binding (A) tends to
keep drug in plasma (lower Vd).
6. A drug has a half-life of 4 hours. Approximately how many hours will it take to
reach steady state?
• A) 4 hours
• B) 8 hours
• C) 20 hours
• D) 40 hours
Answer: C
*Rationale: Steady state is achieved after approximately 5 half-lives (4 hours × 5 =
20 hours). At 1 half-life, 50%; 2 half-lives, 75%; 3 half-lives, 87.5%; 4 half-lives,
93.75%; 5 half-lives, 96.875%.*
7. A drug follows first-order elimination kinetics. Which statement is correct?
• A) A constant amount of drug is eliminated per unit time
• B) A constant fraction of drug is eliminated per unit time
• C) Elimination rate is independent of drug concentration
• D) Zero-order kinetics describes most drugs
Answer: B
*Rationale: First-order kinetics: constant fraction (e.g., 50% per hour) eliminated,
, half-life constant, elimination rate proportional to concentration. A describes zero-
order kinetics.*
8. A patient with alcohol intoxication has a blood alcohol level of 200 mg/dL. The
rate of elimination is constant regardless of concentration. This is an example of:
• A) First-order kinetics
• B) Zero-order kinetics
• C) Michaelis-Menten kinetics (saturable)
• D) Second-order kinetics
Answer: B
*Rationale: Ethanol elimination follows zero-order kinetics at therapeutic/toxic
levels because the enzyme (alcohol dehydrogenase) is saturated. A constant
amount (e.g., 15-20 mg/dL/hour) is eliminated.*
9. Which of the following is the major site of drug metabolism?
• A) Kidney
• B) Liver
• C) Lungs
• D) Intestine
Answer: B
*Rationale: The liver contains most drug-metabolizing enzymes (cytochrome P450
family, phase II conjugating enzymes). The kidney (A) primarily excretes drugs; gut
(D) and lungs (C) contribute less.*
10. A patient is a poor metabolizer of codeine (CYP2D6 substrate). Which of the
following is most likely?
