Lippincott Illustrated Reviews: Pharmacology— Complete Test
Bank with A Answers for Chapters 1–48
Exam
Section 1: Pharmacokinetics & Pharmacodynamics (Questions 1–10)
1. A drug given intravenously reaches peak concentration immediately. Which
pharmacokinetic process is bypassed?
A) Absorption
B) Distribution
C) Metabolism
D) Excretion
Answer: A) Absorption
Rationale: IV administration places the drug directly into the bloodstream,
bypassing the absorption phase (movement from administration site into blood).
Distribution, metabolism, and excretion still occur.
2. A medication has a half-life of 4 hours. How long will it take for the drug to
reach approximately 94% steady state?
A) 8 hours
B) 12 hours
C) 16 hours
D) 20 hours
Answer: C) 16 hours
Rationale: Steady state is reached after 4–5 half-lives. 4 half-lives = 16 hours (4 ×
4 = 16). At 4 half-lives, ~94% of steady state is achieved.
3. Which phase of drug metabolism typically involves conjugation reactions that
increase water solubility?
A) Phase I (oxidation, reduction, hydrolysis)
B) Phase II (glucuronidation, sulfation, acetylation)
, C) Absorption phase
D) Distribution phase
Answer: B) Phase II
Rationale: Phase II reactions add polar groups (e.g., glucuronic acid) to drugs,
increasing water solubility for renal excretion. Phase I reactions (oxidation via
CYP450) often precede Phase II.
4. A drug is a weak acid with a pKa of 4.5. In which environment will it be mostly
nonionized (lipid-soluble) and able to cross membranes?
A) Stomach (pH 1.5)
B) Blood (pH 7.4)
C) Small intestine (pH 6.5)
D) Urine (pH 8.0)
Answer: A) Stomach (pH 1.5)
Rationale: Weak acids are nonionized (lipid-soluble) when pH < pKa. At pH 1.5
(below pKa 4.5), the drug remains mostly nonionized and can cross gastric
membranes.
5. Which of the following best defines the therapeutic index (TI) of a drug?
A) ED50 / TD50
B) TD50 / ED50
C) ED50 × TD50
D) (TD50 – ED50) / ED50
Answer: B) TD50 / ED50
Rationale: Therapeutic index = TD50 (toxic dose in 50%) divided by ED50
(effective dose in 50%). A higher TI indicates a safer drug.
6. A drug acts as a competitive antagonist at a receptor. Which of the following is
true?
A) It binds irreversibly to the receptor
B) It binds to the same site as the agonist and blocks it
Bank with A Answers for Chapters 1–48
Exam
Section 1: Pharmacokinetics & Pharmacodynamics (Questions 1–10)
1. A drug given intravenously reaches peak concentration immediately. Which
pharmacokinetic process is bypassed?
A) Absorption
B) Distribution
C) Metabolism
D) Excretion
Answer: A) Absorption
Rationale: IV administration places the drug directly into the bloodstream,
bypassing the absorption phase (movement from administration site into blood).
Distribution, metabolism, and excretion still occur.
2. A medication has a half-life of 4 hours. How long will it take for the drug to
reach approximately 94% steady state?
A) 8 hours
B) 12 hours
C) 16 hours
D) 20 hours
Answer: C) 16 hours
Rationale: Steady state is reached after 4–5 half-lives. 4 half-lives = 16 hours (4 ×
4 = 16). At 4 half-lives, ~94% of steady state is achieved.
3. Which phase of drug metabolism typically involves conjugation reactions that
increase water solubility?
A) Phase I (oxidation, reduction, hydrolysis)
B) Phase II (glucuronidation, sulfation, acetylation)
, C) Absorption phase
D) Distribution phase
Answer: B) Phase II
Rationale: Phase II reactions add polar groups (e.g., glucuronic acid) to drugs,
increasing water solubility for renal excretion. Phase I reactions (oxidation via
CYP450) often precede Phase II.
4. A drug is a weak acid with a pKa of 4.5. In which environment will it be mostly
nonionized (lipid-soluble) and able to cross membranes?
A) Stomach (pH 1.5)
B) Blood (pH 7.4)
C) Small intestine (pH 6.5)
D) Urine (pH 8.0)
Answer: A) Stomach (pH 1.5)
Rationale: Weak acids are nonionized (lipid-soluble) when pH < pKa. At pH 1.5
(below pKa 4.5), the drug remains mostly nonionized and can cross gastric
membranes.
5. Which of the following best defines the therapeutic index (TI) of a drug?
A) ED50 / TD50
B) TD50 / ED50
C) ED50 × TD50
D) (TD50 – ED50) / ED50
Answer: B) TD50 / ED50
Rationale: Therapeutic index = TD50 (toxic dose in 50%) divided by ED50
(effective dose in 50%). A higher TI indicates a safer drug.
6. A drug acts as a competitive antagonist at a receptor. Which of the following is
true?
A) It binds irreversibly to the receptor
B) It binds to the same site as the agonist and blocks it
