Answers 100% Guarantee Pass 2026/2027
Pharmacokinetics & Pharmacodynamics (Questions 1–50)
1. The bioavailability of a drug is highest when administered by which route?
A) Oral
B) Subcutaneous
C) Intravenous
D) Intramuscular
Answer C: Intravenous
Rationale: IV administration delivers the entire dose directly into systemic
circulation, bypassing first-pass metabolism and achieving 100% bioavailability.
2. A drug's half-life determines:
A) How quickly it is absorbed
B) How often the drug must be administered
C) The drug's therapeutic index
D) The drug's mechanism of action
Answer B: How often the drug must be administered
Rationale: Half-life determines dosing frequency—drugs with short half-lives
require more frequent dosing to maintain therapeutic levels.
,3. The cytochrome P450 system is primarily located in the:
A) Kidneys
B) Liver
C) Lungs
D) Intestines
Answer B: Liver
Rationale: CYP450 enzymes are predominantly found in the liver and are
responsible for metabolizing drugs, endogenous substances, and toxins.
4. A cytochrome P450 inducer will cause which effect on a substrate drug?
A) Increased serum levels of the substrate
B) Decreased serum levels of the substrate
C) No change in serum levels
D) Increased toxicity
Answer B: Decreased serum levels of the substrate
Rationale: CYP450 inducers increase the metabolism of substrate drugs, resulting
in decreased plasma concentrations and reduced therapeutic effect.
5. Steady state of a drug is typically reached after how many half-lives?
A) 2
B) 4-5
C) 7
,D) 10
Answer B: 4-5
Rationale: Steady state is achieved when drug elimination equals drug
administration, typically occurring after 4-5 half-lives.
6. Pharmacological adverse drug reactions are characterized as:
A) Unpredictable and rare
B) Predictable and dose-related
C) Always severe and life-threatening
D) Not requiring monitoring
Answer B: Predictable and dose-related
Rationale: Pharmacological ADRs are extensions of the drug's known effects,
predictable, dose-related, and account for 85-90% of ADRs.
7. What is the definition of bioavailability?
A) The time it takes for a drug to reach peak concentration
B) The rate and extent to which a drug is absorbed and reaches systemic
circulation
C) The amount of drug that binds to plasma proteins
D) The drug's elimination rate
Answer B: The rate and extent to which a drug is absorbed and reaches
systemic circulation
, Rationale: Bioavailability is affected by route of administration, chemical stability,
solubility, and first-pass metabolism.
8. A patient with renal impairment is prescribed a drug primarily eliminated
by the kidneys. The nurse should be most concerned about:
A) Decreased absorption
B) Decreased distribution
C) Decreased metabolism
D) Decreased elimination
Answer D: Decreased elimination
Rationale: Renal impairment decreases drug elimination, leading to accumulation
and potential toxicity.
9. First-pass metabolism:
A) Increases bioavailability
B) Reduces the amount of active drug reaching systemic circulation
C) Occurs in the kidneys
D) Only affects IV drugs
Answer B: Reduces the amount of active drug reaching systemic circulation
Rationale: First-pass metabolism occurs when drugs absorbed from the GI tract
pass through the liver before reaching systemic circulation.