UCSF U141 PHARMACOLOGY FINAL
EXAM 2026/2027 | 150 VERIFIED
QUESTIONS & ANSWERS WITH
RATIONALES FOR MEPN
Domain 1: Pharmacokinetics & Pharmacodynamics
1. What does pharmacokinetics describe?
A. What the drug does to the body
B. What the body does to the drug (absorption, distribution, metabolism, excretion)
C. Only receptor binding
D. Only adverse effects
Answer: B. Rationale: Pharmacokinetics is the study of ADME processes that determine
drug concentration over time.
2. What does pharmacodynamics describe?
A. Only drug excretion
B. What the drug does to the body, including receptor interactions and therapeutic
effects
C. Only half-life
D. Only drug absorption
Answer: B. Rationale: Pharmacodynamics concerns the biochemical and physiologic
effects of drugs and their mechanisms of action.
3. Which route of administration completely bypasses absorption?
A. Oral
B. Intravenous
C. Intramuscular
D. Subcutaneous
Answer: B. Rationale: IV administration places the drug directly into the bloodstream,
eliminating the absorption step.
4. Which organ is the primary site of drug metabolism for most drugs?
A. Kidney
B. Liver
C. Lung
D. Spleen
,Answer: B. Rationale: The liver is the principal organ of drug metabolism via
cytochrome P450 and other enzymes.
5. Which organ is primarily responsible for excretion of most drugs and their
metabolites?
A. Liver
B. Kidneys
C. Skin
D. Intestine only
Answer: B. Rationale: Renal excretion is the major route for elimination of many drugs
and metabolites.
6. What is the first-pass effect?
A. Rapid renal clearance
B. Metabolism of an orally administered drug by the liver before it reaches systemic
circulation
C. Enhanced absorption in the stomach
D. Protein binding in plasma
Answer: B. Rationale: Oral drugs absorbed from the GI tract pass through the portal
circulation and may be extensively metabolized before systemic distribution.
7. What is drug half-life?
A. Time to peak effect
B. Time required for the plasma concentration to decrease by 50%
C. Duration of receptor occupancy
D. Time to steady state only
Answer: B. Rationale: Half-life is the time required for the plasma concentration of a
drug to decrease by 50%.
8. What is the definition of steady state?
A. The point at which drug absorption equals elimination
B. The point at which drug absorption equals elimination, resulting in a constant
plasma concentration
C. The peak plasma concentration
D. The trough plasma concentration
Answer: B. Rationale: Steady state is reached when the rate of drug administration
equals the rate of drug elimination.
9. Which CYP450 enzyme is responsible for metabolizing a large proportion of
commonly prescribed drugs?
A. CYP1A2 only
B. CYP3A
C. CYP2D6 exclusively
D. CYP2C19 only
,Answer: B. Rationale: CYP3A4 metabolizes a substantial fraction (approximately 50%)
of clinically used drugs.
10. What is the therapeutic index (TI)?
A. The ratio of the median effective dose to the median lethal dose
B. The ratio of the median lethal dose (LD50) to the median effective dose (ED50)
C. The ratio of the peak to trough concentration
D. The time to onset of action
Answer: B. Rationale: TI = LD50 / ED50. A narrow therapeutic index means there is a
small margin between therapeutic and toxic doses.
11. Which of the following describes a competitive antagonist?
A. Binds to a different site than the agonist
B. Binds reversibly to the same receptor site as the agonist, shifting the dose-response
curve to the right
C. Permanently inactivates the receptor
D. Increases the maximum efficacy of the agonist
Answer: B. Rationale: Competitive antagonists bind reversibly to the agonist binding
site, shifting the dose-response curve to the right but not decreasing maximal efficacy.
12. What is the primary mechanism of action of a non-competitive antagonist?
A. Competes with the agonist for the same binding site
B. Binds to an allosteric site or irreversibly to the receptor, reducing the maximum
efficacy of the agonist
C. Increases the affinity of the agonist
D. Mimics the effects of the agonist
Answer: B. Rationale: Non-competitive antagonists reduce the maximal effect (efficacy)
of the agonist, regardless of the agonist concentration.
13. Which of the following routes of administration has the highest
bioavailability?
A. Oral
B. Rectal
C. Intravenous
D. Subcutaneous
Answer: C. Rationale: Intravenous administration delivers the drug directly into the
systemic circulation, resulting in 100% bioavailability.
14. Which of the following factors can increase drug metabolism?
A. Hepatic impairment
B. Enzyme induction (e.g., by rifampin, carbamazepine)
C. Enzyme inhibition (e.g., by ketoconazole, erythromycin)
D. Decreased renal blood flow
, Answer: B. Rationale: Enzyme inducers increase the synthesis of CYP450 enzymes,
leading to faster metabolism of drugs.
15. What is the effect of an enzyme inhibitor on the plasma concentration of a
drug metabolized by that enzyme?
A. Decreases plasma concentration
B. Increases plasma concentration
C. Has no effect
D. Increases renal excretion
Answer: B. Rationale: Enzyme inhibitors decrease the rate of drug metabolism, leading
to increased plasma concentrations and toxicity risk.
16. What is the purpose of the "rights" of medication administration?
A. To increase nursing workload
B. To prevent medication errors and ensure patient safety
C. To satisfy insurance requirements
D. To speed up the medication process
Answer: B. Rationale: The rights of medication administration are a standard safety
checklist to prevent medication errors.
17. When is it appropriate for a nurse to administer a medication via a route
other than prescribed?
A. When the patient refuses the oral route
B. Never, unless a new order is obtained from the prescriber
C. When the nurse is in a hurry
D. When the patient is asleep
Answer: B. Rationale: Nurses must administer medications via the prescribed route.
Changing the route requires a new order from the prescriber.
18. Which of the following is a legal requirement for a medication order?
A. Must be written in ink
B. Must be signed by the prescriber
C. Must include the drug, dose, route, and frequency
D. All of the above
Answer: D. Rationale: A legal medication order must be written in ink, signed by the
prescriber, and include the drug name, dose, route, and frequency.
19. Which needle gauge is appropriate for an intramuscular injection of a thick
medication?
A. 25 G
B. 18 G
C. 30 G
D. 27 G
EXAM 2026/2027 | 150 VERIFIED
QUESTIONS & ANSWERS WITH
RATIONALES FOR MEPN
Domain 1: Pharmacokinetics & Pharmacodynamics
1. What does pharmacokinetics describe?
A. What the drug does to the body
B. What the body does to the drug (absorption, distribution, metabolism, excretion)
C. Only receptor binding
D. Only adverse effects
Answer: B. Rationale: Pharmacokinetics is the study of ADME processes that determine
drug concentration over time.
2. What does pharmacodynamics describe?
A. Only drug excretion
B. What the drug does to the body, including receptor interactions and therapeutic
effects
C. Only half-life
D. Only drug absorption
Answer: B. Rationale: Pharmacodynamics concerns the biochemical and physiologic
effects of drugs and their mechanisms of action.
3. Which route of administration completely bypasses absorption?
A. Oral
B. Intravenous
C. Intramuscular
D. Subcutaneous
Answer: B. Rationale: IV administration places the drug directly into the bloodstream,
eliminating the absorption step.
4. Which organ is the primary site of drug metabolism for most drugs?
A. Kidney
B. Liver
C. Lung
D. Spleen
,Answer: B. Rationale: The liver is the principal organ of drug metabolism via
cytochrome P450 and other enzymes.
5. Which organ is primarily responsible for excretion of most drugs and their
metabolites?
A. Liver
B. Kidneys
C. Skin
D. Intestine only
Answer: B. Rationale: Renal excretion is the major route for elimination of many drugs
and metabolites.
6. What is the first-pass effect?
A. Rapid renal clearance
B. Metabolism of an orally administered drug by the liver before it reaches systemic
circulation
C. Enhanced absorption in the stomach
D. Protein binding in plasma
Answer: B. Rationale: Oral drugs absorbed from the GI tract pass through the portal
circulation and may be extensively metabolized before systemic distribution.
7. What is drug half-life?
A. Time to peak effect
B. Time required for the plasma concentration to decrease by 50%
C. Duration of receptor occupancy
D. Time to steady state only
Answer: B. Rationale: Half-life is the time required for the plasma concentration of a
drug to decrease by 50%.
8. What is the definition of steady state?
A. The point at which drug absorption equals elimination
B. The point at which drug absorption equals elimination, resulting in a constant
plasma concentration
C. The peak plasma concentration
D. The trough plasma concentration
Answer: B. Rationale: Steady state is reached when the rate of drug administration
equals the rate of drug elimination.
9. Which CYP450 enzyme is responsible for metabolizing a large proportion of
commonly prescribed drugs?
A. CYP1A2 only
B. CYP3A
C. CYP2D6 exclusively
D. CYP2C19 only
,Answer: B. Rationale: CYP3A4 metabolizes a substantial fraction (approximately 50%)
of clinically used drugs.
10. What is the therapeutic index (TI)?
A. The ratio of the median effective dose to the median lethal dose
B. The ratio of the median lethal dose (LD50) to the median effective dose (ED50)
C. The ratio of the peak to trough concentration
D. The time to onset of action
Answer: B. Rationale: TI = LD50 / ED50. A narrow therapeutic index means there is a
small margin between therapeutic and toxic doses.
11. Which of the following describes a competitive antagonist?
A. Binds to a different site than the agonist
B. Binds reversibly to the same receptor site as the agonist, shifting the dose-response
curve to the right
C. Permanently inactivates the receptor
D. Increases the maximum efficacy of the agonist
Answer: B. Rationale: Competitive antagonists bind reversibly to the agonist binding
site, shifting the dose-response curve to the right but not decreasing maximal efficacy.
12. What is the primary mechanism of action of a non-competitive antagonist?
A. Competes with the agonist for the same binding site
B. Binds to an allosteric site or irreversibly to the receptor, reducing the maximum
efficacy of the agonist
C. Increases the affinity of the agonist
D. Mimics the effects of the agonist
Answer: B. Rationale: Non-competitive antagonists reduce the maximal effect (efficacy)
of the agonist, regardless of the agonist concentration.
13. Which of the following routes of administration has the highest
bioavailability?
A. Oral
B. Rectal
C. Intravenous
D. Subcutaneous
Answer: C. Rationale: Intravenous administration delivers the drug directly into the
systemic circulation, resulting in 100% bioavailability.
14. Which of the following factors can increase drug metabolism?
A. Hepatic impairment
B. Enzyme induction (e.g., by rifampin, carbamazepine)
C. Enzyme inhibition (e.g., by ketoconazole, erythromycin)
D. Decreased renal blood flow
, Answer: B. Rationale: Enzyme inducers increase the synthesis of CYP450 enzymes,
leading to faster metabolism of drugs.
15. What is the effect of an enzyme inhibitor on the plasma concentration of a
drug metabolized by that enzyme?
A. Decreases plasma concentration
B. Increases plasma concentration
C. Has no effect
D. Increases renal excretion
Answer: B. Rationale: Enzyme inhibitors decrease the rate of drug metabolism, leading
to increased plasma concentrations and toxicity risk.
16. What is the purpose of the "rights" of medication administration?
A. To increase nursing workload
B. To prevent medication errors and ensure patient safety
C. To satisfy insurance requirements
D. To speed up the medication process
Answer: B. Rationale: The rights of medication administration are a standard safety
checklist to prevent medication errors.
17. When is it appropriate for a nurse to administer a medication via a route
other than prescribed?
A. When the patient refuses the oral route
B. Never, unless a new order is obtained from the prescriber
C. When the nurse is in a hurry
D. When the patient is asleep
Answer: B. Rationale: Nurses must administer medications via the prescribed route.
Changing the route requires a new order from the prescriber.
18. Which of the following is a legal requirement for a medication order?
A. Must be written in ink
B. Must be signed by the prescriber
C. Must include the drug, dose, route, and frequency
D. All of the above
Answer: D. Rationale: A legal medication order must be written in ink, signed by the
prescriber, and include the drug name, dose, route, and frequency.
19. Which needle gauge is appropriate for an intramuscular injection of a thick
medication?
A. 25 G
B. 18 G
C. 30 G
D. 27 G
