Test Bank | UTA | 150 Questions & Answers
Section 1: Pharmacokinetics & Pharmacodynamics (Questions 1-25)
Q1. A patient with chronic kidney disease (Stage 4) is prescribed a medication that is primarily
renally excreted. The nurse anticipates that the patient will require:
A. A higher dose to achieve a therapeutic effect.
B. A lower dose or longer dosing interval to prevent toxicity.
C. The same dose as a patient with normal renal function.
D. An increased frequency of administration.
Answer: B
Rationale: Reduced renal clearance leads to drug accumulation. Decreasing the dose or
extending the interval maintains therapeutic levels without toxicity.
Q2. A patient with heart failure is prescribed digoxin. Which physiological change associated
with aging would most likely increase the risk of digoxin toxicity?
A. Increased glomerular filtration rate
B. Decreased lean body mass
C. Increased hepatic blood flow
D. Decreased serum albumin
Answer: D
Rationale: Aging is associated with decreased serum albumin. Digoxin is moderately
protein-bound. Lower albumin levels increase the free (active) fraction of the drug, leading to a
greater pharmacological effect and higher risk of toxicity.
Q3. A drug has a half-life of 24 hours. Approximately how many hours will it take for the drug to
reach steady state?
A. 24 hours
B. 48 hours
C. 120 hours
D. 240 hours
,Answer: C
Rationale: Steady state is achieved after approximately 4-5 half-lives. With a half-life of 24
hours, 4-5 half-lives equal 96-120 hours.
Q4. Which cytochrome P450 enzyme is most commonly involved in clinically significant
drug-drug interactions?
A. CYP1A2
B. CYP2D6
C. CYP3A4
D. CYP2C9
Answer: C
Rationale: CYP3A4 metabolizes approximately 50% of marketed drugs, including statins,
calcium channel blockers, and benzodiazepines. It is highly susceptible to inhibition (grapefruit
juice, ketoconazole) and induction (rifampin, carbamazepine).
Q5. A patient is prescribed a drug that is a weak acid (pKa 4.4). In which part of the
gastrointestinal tract will absorption be most rapid?
A. Mouth (pH 7.0)
B. Stomach (pH 1.5)
C. Duodenum (pH 6.0)
D. Colon (pH 7.5)
Answer: B
Rationale: Weak acids are best absorbed in acidic environments where they remain non-ionized
(lipid-soluble). In the stomach's acidic pH, the drug is predominantly non-ionized, allowing for
passive diffusion across the gastric mucosa.
Q6. What is the difference between pharmacokinetics and pharmacodynamics?
A. Pharmacokinetics is what the body does to the drug; pharmacodynamics is what the drug
does to the body.
B. Pharmacokinetics is what the drug does to the body; pharmacodynamics is what the body
does to the drug.
C. Both are the same process.
D. Pharmacokinetics applies only to IV drugs.
Answer: A
,Rationale: Pharmacokinetics describes the impact of the body on drugs (ADME).
Pharmacodynamics describes the impact of drugs on the body (mechanism of action, effects).
Q7. A patient with end-stage renal disease (eGFR <15 mL/min) is prescribed a medication that
is 70% renally excreted. The nurse practitioner should anticipate:
A. Increasing the dose by 50%
B. Decreasing the dosing frequency
C. Changing to a prodrug
D. Adding a diuretic to enhance excretion
Answer: B
Rationale: Reduced renal clearance leads to drug accumulation. Decreasing the dosing
frequency maintains therapeutic levels without toxicity. Increasing the dose would worsen
toxicity.
Q8. A drug with high first-pass effect is given orally. The NP understands that:
A. The drug will have increased bioavailability
B. The drug must be given via a non-oral route to avoid extensive hepatic metabolism
C. Gastric pH will alter absorption significantly
D. Protein binding will be decreased
Answer: B
Rationale: High first-pass effect means the liver metabolizes much of the drug before it reaches
systemic circulation. IV, IM, or sublingual routes bypass portal circulation.
Q9. A patient develops tolerance to morphine. This is most likely due to:
A. Increased renal excretion
B. Downregulation of opioid receptors
C. Upregulation of P-glycoprotein in the gut
D. Decreased liver blood flow
Answer: B
Rationale: Chronic opioid use leads to receptor desensitization and downregulation, requiring
higher doses for the same effect. Tolerance is pharmacodynamic, not pharmacokinetic.
Q10. Which medication exhibits nonlinear (zero-order) pharmacokinetics at therapeutic doses?
A. Lisinopril
, B. Phenytoin
C. Metformin
D. Amoxicillin
Answer: B
Rationale: Phenytoin saturates hepatic enzymes at therapeutic levels, leading to
disproportionate increases in serum concentration with dose adjustments. Others exhibit
first-order kinetics.
Q11. A patient takes warfarin. Starting rifampin (a potent CYP inducer) will likely:
A. Increase INR and bleeding risk
B. Decrease INR and reduce anticoagulant effect
C. Have no effect on INR
D. Cause warfarin toxicity
Answer: B
Rationale: Rifampin induces CYP2C9 (warfarin metabolism), lowering warfarin levels and INR.
Dose adjustment upward may be needed.
Q12. What is the volume of distribution (Vd) of a drug?
A. The actual volume of blood in the body
B. The apparent volume in which a drug is distributed
C. The volume of urine produced per hour
D. The dose of drug per kilogram of body weight
Answer: B
Rationale: Volume of distribution is a theoretical volume that relates the amount of drug in the
body to its plasma concentration. A high Vd indicates extensive tissue distribution.
Q13. A drug with a high volume of distribution (Vd) is likely to:
A. Remain primarily in the bloodstream
B. Be extensively distributed into tissues
C. Be rapidly excreted by the kidneys
D. Have a short half-life
Answer: B