ADVANCED PHARMACOLOGY:
PHARMACOKINETICS AND
PHARMACODYNAMICS (NURS 6521N
WEEK 2) QUESTIONS WITH COMPLETE
AND VERIFIED SOLUTIONS: WALDEN
UNIVERSITY
1. A drug that is a substrate for P-glycoprotein (P-gp) is administered orally. What is the
primary effect of P-gp in the intestinal mucosa?
A. It facilitates active transport into the systemic circulation.
B. It acts as a Phase II enzyme to conjugate the drug for excretion.
C. It pumps drug molecules back into the intestinal lumen, reducing absorption.
D. It increases the drug’s lipid solubility to enhance passive diffusion.
Answer: C
Conceptual Explanation: P-glycoprotein is an efflux pump found in the gut, brain, and
kidneys. In the intestine, it moves drugs from the cells back into the lumen, decreasing
overall bioavailability.
,2. Which factor most significantly affects the distribution of a highly lipophilic drug in an
obese patient?
A. Increased volume of distribution (Vd).
B. Decreased glomerular filtration rate.
C. Reduced serum albumin levels.
D. Enhanced first-pass metabolism.
Answer: A
Conceptual Explanation: Lipophilic drugs have a high affinity for adipose tissue. In obese
patients, the increased body fat leads to a larger volume of distribution (Vd) for these
drugs, potentially requiring a higher loading dose.
3. A patient is taking Phenobarbital, a known inducer of the Cytochrome P450 system. What
is the likely result when a second drug, which is a substrate of the same system, is added?
A. Increased serum concentration of the second drug.
B. Rapid development of drug hypersensitivity.
C. No change in the metabolism of the second drug.
D. Decreased serum concentration of the second drug.
Answer: D
, Conceptual Explanation: Enzyme inducers like Phenobarbital increase the rate of drug
metabolism for substrates of those enzymes, leading to lower serum levels and potentially
decreased therapeutic effect.
4. What characterizes a drug that acts as a ‘Partial Agonist’?
A. It binds to the receptor but produces no biological response.
B. It produces a maximal response even at low receptor occupancy.
C. It has lower intrinsic activity than a full agonist.
D. It binds irreversibly to the active site of the receptor.
Answer: C
Conceptual Explanation: Partial agonists bind to receptors but have lower intrinsic
activity, meaning they cannot produce the same maximal effect as a full agonist, even if all
receptors are occupied.
5. A drug has a half-life of 6 hours. If the drug is administered via continuous infusion, how
long will it take for the drug to reach steady-state plasma concentrations?
A. 6 hours
B. 24 to 30 hours
C. 12 hours
D. 48 to 60 hours
Answer: B
PHARMACOKINETICS AND
PHARMACODYNAMICS (NURS 6521N
WEEK 2) QUESTIONS WITH COMPLETE
AND VERIFIED SOLUTIONS: WALDEN
UNIVERSITY
1. A drug that is a substrate for P-glycoprotein (P-gp) is administered orally. What is the
primary effect of P-gp in the intestinal mucosa?
A. It facilitates active transport into the systemic circulation.
B. It acts as a Phase II enzyme to conjugate the drug for excretion.
C. It pumps drug molecules back into the intestinal lumen, reducing absorption.
D. It increases the drug’s lipid solubility to enhance passive diffusion.
Answer: C
Conceptual Explanation: P-glycoprotein is an efflux pump found in the gut, brain, and
kidneys. In the intestine, it moves drugs from the cells back into the lumen, decreasing
overall bioavailability.
,2. Which factor most significantly affects the distribution of a highly lipophilic drug in an
obese patient?
A. Increased volume of distribution (Vd).
B. Decreased glomerular filtration rate.
C. Reduced serum albumin levels.
D. Enhanced first-pass metabolism.
Answer: A
Conceptual Explanation: Lipophilic drugs have a high affinity for adipose tissue. In obese
patients, the increased body fat leads to a larger volume of distribution (Vd) for these
drugs, potentially requiring a higher loading dose.
3. A patient is taking Phenobarbital, a known inducer of the Cytochrome P450 system. What
is the likely result when a second drug, which is a substrate of the same system, is added?
A. Increased serum concentration of the second drug.
B. Rapid development of drug hypersensitivity.
C. No change in the metabolism of the second drug.
D. Decreased serum concentration of the second drug.
Answer: D
, Conceptual Explanation: Enzyme inducers like Phenobarbital increase the rate of drug
metabolism for substrates of those enzymes, leading to lower serum levels and potentially
decreased therapeutic effect.
4. What characterizes a drug that acts as a ‘Partial Agonist’?
A. It binds to the receptor but produces no biological response.
B. It produces a maximal response even at low receptor occupancy.
C. It has lower intrinsic activity than a full agonist.
D. It binds irreversibly to the active site of the receptor.
Answer: C
Conceptual Explanation: Partial agonists bind to receptors but have lower intrinsic
activity, meaning they cannot produce the same maximal effect as a full agonist, even if all
receptors are occupied.
5. A drug has a half-life of 6 hours. If the drug is administered via continuous infusion, how
long will it take for the drug to reach steady-state plasma concentrations?
A. 6 hours
B. 24 to 30 hours
C. 12 hours
D. 48 to 60 hours
Answer: B
