100% Correct Answers | Regis College (2026/2027
Edition)
PREPARED FOR:
NU665 - Regis College Week 8 Midterm Examination
DOCUMENT INCLUDES:
● Exam-style questions
● Correct answers
● Detailed rationales
● Key topics covered
TOPICS COVERED:
● Pharmacokinetics & Pharmacodynamics
● Drug Classifications & Mechanisms of Action
● Prescribing Principles & Evidence-Based Guidelines
● Drug Interactions & Adverse Effects
● Monitoring Parameters & Therapeutic Drug Levels
● Special Populations (Pediatrics, Geriatrics, Pregnancy/Lactation)
● Controlled Substances & Regulatory Issues
● Clinical Decision-Making & Case-Based Reasoning
PURPOSE:
This comprehensive midterm exam prep guide is designed to help NU665 students
master advanced nursing concepts, strengthen clinical reasoning, and confidently
prepare for the Regis College Week 8 Midterm Examination.
SECTION 1: PHARMACOKINETICS & PHARMACODYNAMICS
,Question 1
A 68-year-old patient with chronic heart failure is prescribed digoxin 0.125 mg daily. The
nurse practitioner knows that digoxin has a narrow therapeutic index. Which laboratory
value is most critical to monitor to prevent toxicity?
A. Serum potassium
B. Serum sodium
C. Serum calcium
D. Serum magnesium
Correct Answer: A
Rationale: Digoxin toxicity is significantly potentiated by hypokalemia because
potassium and digoxin compete for the same binding site on the Na+/K+-ATPase pump.
Low serum potassium increases digoxin binding and toxicity risk. While magnesium and
calcium can also influence cardiac conduction, potassium is the most critical parameter
to monitor in patients on digoxin therapy. Sodium is not directly related to digoxin
toxicity mechanisms.
Question 2
A patient with renal impairment is prescribed a medication that is primarily eliminated
by the kidneys. Which pharmacokinetic parameter is most directly affected by reduced
renal function?
A. Absorption
B. Distribution
C. Metabolism
D. Excretion
Correct Answer: D
,Rationale: Excretion (elimination) is the pharmacokinetic phase most directly impacted
by renal impairment. When renal function declines, drugs eliminated by the kidneys
accumulate, increasing the risk of toxicity. Dosing adjustments based on creatinine
clearance or glomerular filtration rate (GFR) are essential. Absorption occurs primarily in
the GI tract, distribution depends on protein binding and tissue perfusion, and
metabolism occurs mainly in the liver.
Question 3
Which term describes the amount of drug that reaches the systemic circulation
unchanged after administration?
A. Bioavailability
B. Half-life
C. Volume of distribution
D. Therapeutic index
Correct Answer: A
Rationale: Bioavailability (F) is the fraction of an administered dose of unchanged drug
that reaches the systemic circulation. It is 100% for intravenous administration and
variable for oral and other routes due to first-pass metabolism and incomplete
absorption. Half-life is the time for drug concentration to decrease by 50%. Volume of
distribution relates drug amount in the body to plasma concentration. Therapeutic index
is the ratio of toxic dose to effective dose.
Question 4
A drug with high protein binding (e.g., warfarin, 99% bound) is administered concurrently
with another highly protein-bound drug. What is the primary clinical concern?
A. Decreased absorption of the first drug
B. Displacement from protein binding sites, increasing free drug concentration
, C. Increased metabolism of the second drug
D. Enhanced renal excretion of both drugs
Correct Answer: B
Rationale: When two highly protein-bound drugs are administered together, they may
compete for binding sites on albumin. Displacement of the first drug increases the free
(unbound) fraction, which is pharmacologically active. This can lead to enhanced
pharmacological effects and potential toxicity, even though total drug concentration
may remain unchanged. This is particularly dangerous with drugs having narrow
therapeutic indices like warfarin.
Question 5
Which receptor mechanism best describes the action of beta-blockers such as
metoprolol?
A. Agonist at beta-adrenergic receptors
B. Competitive antagonist at beta-adrenergic receptors
C. Noncompetitive antagonist at beta-adrenergic receptors
D. Inverse agonist at beta-adrenergic receptors
Correct Answer: B
Rationale: Beta-blockers like metoprolol are competitive antagonists at beta-adrenergic
receptors. They bind reversibly to the receptor without activating it, blocking the binding
of endogenous catecholamines (epinephrine and norepinephrine). Their effects can be
overcome by increasing agonist concentration. They are not agonists (which activate
receptors), noncompetitive antagonists (which bind irreversibly or allosterically), or
inverse agonists (which reduce constitutive receptor activity).
Question 6