NU 518 MIDTERM EXAM 2026/2027 |
ADVANCED PHARMACOLOGY | 75 VERIFIED
Q&A | DETAILED RATIONALES | NGN-
ALIGNED | PASS GUARANTEED – A+ GRADED
SECTION 1: PHARMACOKINETICS AND PHARMACODYNAMICS - Questions 1-8
Q1: Bioavailability Definition
The student is reviewing pharmacokinetic principles. What does the term "bioavailability" refer to?
A. The proportion of a drug that reaches systemic circulation unchanged
B. The rate of drug elimination from the body
C. The volume of distribution of a drug
D. The degree of protein binding of a drug
Correct Answer: A
Rationale: Bioavailability is the fraction (percentage) of an administered drug dose that reaches the
systemic circulation in an unchanged form. Intravenous administration has 100% bioavailability. Oral
bioavailability is reduced by incomplete absorption and first-pass metabolism. [100% CORRECT]
Q2: Therapeutic Window
The student is reviewing drug safety. What is the therapeutic window of a drug?
A. The range of plasma concentrations between the minimum effective concentration and the
minimum toxic concentration
B. The time it takes for a drug to reach peak plasma concentration
C. The duration of action of a drug
D. The difference between the lethal dose and the effective dose
Correct Answer: A
Rationale: The therapeutic window (or therapeutic index) is the range of drug concentrations that
produces the desired therapeutic effect without causing unacceptable toxicity. Drugs with a narrow
therapeutic window (e.g., digoxin, lithium, warfarin) require careful monitoring. [100% CORRECT]
Q3: Active Metabolite
The student is reviewing drug metabolism. Which drug is a prodrug that requires metabolic
activation?
,2
A. Clopidogrel
B. Morphine
C. Lisinopril
D. Metoprolol
Correct Answer: A
Rationale: Clopidogrel is a prodrug that must be metabolized by CYP2C19 to its active metabolite to
inhibit platelet aggregation. Morphine, lisinopril, and metoprolol are active parent drugs. [100%
CORRECT]
Q4: Enterohepatic Recirculation
The student is reviewing pharmacokinetics. What is enterohepatic recirculation?
A. The process by which a drug is excreted in bile and then reabsorbed from the intestine
B. The process by which a drug is metabolized in the liver
C. The process by which a drug is excreted in urine
D. The process by which a drug is distributed to tissues
Correct Answer: A
Rationale: Enterohepatic recirculation occurs when a drug or its metabolite is excreted into bile,
enters the intestine, and is reabsorbed into the bloodstream, prolonging the drug's effect. Examples
include oral contraceptives and some antibiotics. [100% CORRECT]
Q5: Loading Dose
The student is reviewing dosing strategies. When is a loading dose indicated?
A. When a rapid therapeutic drug level is needed
B. When a drug has a long half-life
C. When a drug has a narrow therapeutic window
D. When a drug is highly protein-bound
Correct Answer: A
Rationale: A loading dose is a larger initial dose given to rapidly achieve therapeutic plasma
concentrations, especially for drugs with long half-lives (e.g., digoxin, amiodarone). Maintenance
doses follow to sustain the level. [100% CORRECT]
Q6: Pharmacodynamic Tolerance
The student is reviewing pharmacodynamics. What is pharmacodynamic tolerance?
A. Reduced response to a drug after repeated administration due to receptor downregulation
B. Increased metabolism of a drug after repeated administration
C. Reduced absorption of a drug after repeated administration
D. Increased excretion of a drug after repeated administration
, 3
Correct Answer: A
Rationale: Pharmacodynamic tolerance occurs when repeated administration of a drug leads to
decreased responsiveness, often due to receptor downregulation or desensitization. Examples
include opioids and beta-agonists. [100% CORRECT]
Q7: CYP450 Inducer Effect
The student is reviewing drug interactions. A patient taking oral contraceptives is prescribed
rifampin. What is the expected effect?
A. Decreased contraceptive effectiveness
B. Increased contraceptive effectiveness
C. No change in contraceptive effectiveness
D. Increased risk of contraceptive toxicity
Correct Answer: A
Rationale: Rifampin is a potent CYP3A4 inducer that increases the metabolism of oral
contraceptives, reducing their effectiveness and increasing the risk of unintended pregnancy.
Alternative or additional contraception is recommended. [100% CORRECT]
Q8: P-glycoprotein
The student is reviewing drug transport. What is the function of P-glycoprotein?
A. It is an efflux transporter that pumps drugs out of cells
B. It is an influx transporter that brings drugs into cells
C. It metabolizes drugs in the liver
D. It binds drugs to plasma proteins
Correct Answer: A
Rationale: P-glycoprotein is an efflux transporter located in the intestine, blood-brain barrier, and
kidneys. It pumps drugs out of cells, reducing absorption and penetration into the CNS. Inhibitors
(e.g., verapamil) can increase drug levels. [100% CORRECT]
SECTION 2: AUTONOMIC NERVOUS SYSTEM PHARMACOLOGY - Questions 9-16
Q9: Muscarinic Agonist Effect
The student is reviewing cholinergic drugs. Which effect is produced by a muscarinic agonist?
A. Decreased heart rate
B. Bronchodilation
C. Mydriasis
D. Urinary retention
Correct Answer: A