RN PHARMACOLOGY A RELIAS EXAM 2026/2027 | 100%
Correct Answers with Complete Solutions | Nursing
Competency Assessment | Pass Guaranteed - A+ Graded
Domain 1: Pharmacokinetics & Pharmacodynamics (12 Questions)
Q1: A 68-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. The
nurse reviews the patient's laboratory results and notes a serum potassium level of 3.2
mEq/L and a digoxin level of 1.8 ng/mL. Based on pharmacokinetic principles, what is
the nurse's priority action?
A. Administer the digoxin as ordered since the level is within therapeutic range
B. Hold the digoxin and notify the provider due to hypokalemia increasing digoxin
toxicity risk
C. Administer potassium supplements and give the digoxin
D. Request a repeat digoxin level before administration
Correct Answer: B
Rationale: Hypokalemia (K+ < 3.5 mEq/L) significantly increases the risk of digoxin
toxicity because potassium and digoxin compete for binding sites on the
Na+/K+-ATPase pump. When potassium levels are low, digoxin binds more readily to
these sites, increasing its pharmacodynamic effects and toxicity risk (arrhythmias,
nausea, visual disturbances). Although the digoxin level of 1.8 ng/mL is within the
therapeutic range (0.5-2.0 ng/mL), the concurrent hypokalemia creates a dangerous
situation. The nurse must hold the dose and notify the provider immediately. Option A is
incorrect because therapeutic levels do not guarantee safety when electrolyte
imbalances exist. Option C is incorrect because the nurse should not administer digoxin
without provider notification and correction of the hypokalemia. Option D delays
necessary intervention.
,Q2: A patient receiving IV gentamicin for a severe infection has the following
pharmacokinetic parameters: peak level 12 mcg/mL (drawn 30 minutes after infusion),
trough level 3 mcg/mL (drawn immediately before next dose). The therapeutic range for
gentamicin is peak 5-10 mcg/mL and trough <2 mcg/mL. What is the appropriate
nursing action?
A. Continue the current dosing regimen as ordered
B. Hold the next dose and notify the provider of elevated peak and trough levels
C. Administer the next dose immediately to maintain therapeutic levels
D. Request a repeat trough level before the next administration
Correct Answer: B
Rationale: Both the peak (12 mcg/mL) and trough (3 mcg/mL) levels exceed the
therapeutic ranges for gentamicin. Elevated peak levels increase the risk of
nephrotoxicity, while elevated trough levels indicate drug accumulation and increased
risk of both nephrotoxicity and ototoxicity. Aminoglycosides exhibit
concentration-dependent killing but require careful monitoring due to their narrow
therapeutic index. The nurse must hold the next dose and notify the provider
immediately to prevent permanent renal and auditory damage. Option A is incorrect
because continuing the current regimen will worsen toxicity. Option C is dangerous and
will further increase drug levels. Option D delays necessary intervention when clear
evidence of accumulation exists.
Q3: A nurse is educating a patient prescribed warfarin 5 mg daily. The patient asks why
they need to avoid eating large amounts of spinach and kale. Based on
pharmacodynamic principles, what is the nurse's best response?
A. "These foods contain vitamin K, which antagonizes warfarin's mechanism of action
and can decrease its effectiveness."
B. "These foods are high in fiber, which decreases warfarin absorption from the GI tract."
C. "These foods contain calcium, which binds to warfarin and prevents its absorption."
,D. "These foods increase your metabolism, causing warfarin to be eliminated too
quickly."
Correct Answer: A
Rationale: Warfarin is a vitamin K antagonist that inhibits the synthesis of vitamin
K-dependent clotting factors (II, VII, IX, X). Vitamin K is a fat-soluble vitamin abundant in
leafy green vegetables (spinach, kale, broccoli). Consuming large amounts of vitamin
K-rich foods provides additional substrate for clotting factor synthesis, antagonizing
warfarin's pharmacodynamic effects and potentially decreasing INR, increasing
thrombosis risk. Patients should maintain consistent vitamin K intake rather than
avoiding it completely. Option B is incorrect because fiber does not significantly affect
warfarin absorption. Option C is incorrect because calcium does not bind warfarin.
Option D is incorrect because these foods do not induce warfarin metabolism.
Q4: A 45-year-old patient with liver cirrhosis is prescribed lorazepam 2 mg PO for
anxiety. The nurse recognizes that this patient is at increased risk for drug toxicity. What
pharmacokinetic principle explains this risk?
A. Decreased drug absorption due to portal hypertension
B. Decreased hepatic metabolism leading to prolonged drug half-life and accumulation
C. Increased renal excretion of the active drug compound
D. Increased volume of distribution due to decreased plasma proteins
Correct Answer: B
Rationale: Lorazepam undergoes hepatic metabolism via glucuronidation. In liver
cirrhosis, hepatocellular damage reduces metabolic enzyme function, decreasing drug
metabolism and prolonging half-life. This leads to drug accumulation and increased risk
of sedation, respiratory depression, and coma. While Option D (increased volume of
distribution due to decreased albumin) occurs in liver disease, it primarily affects highly
protein-bound drugs. Lorazepam is relatively less protein-bound compared to other
benzodiazepines. The primary concern is decreased metabolism. Option A is incorrect
, because absorption is not significantly affected. Option C is incorrect because renal
excretion is not increased.
Q5: A patient with chronic kidney disease (CrCl 25 mL/min) is prescribed ciprofloxacin
500 mg PO twice daily for a urinary tract infection. The usual dose is 500 mg every 12
hours. What adjustment should the nurse anticipate?
A. No adjustment needed; administer as prescribed
B. Reduced dose to 250 mg every 12 hours or extended interval to 500 mg every 24
hours
C. Increased dose to 750 mg every 12 hours due to decreased absorption
D. Change to IV administration to ensure adequate drug levels
Correct Answer: B
Rationale: Ciprofloxacin is primarily eliminated unchanged by the kidneys
(approximately 50-70%). In chronic kidney disease with CrCl <30 mL/min, dosage
adjustment is required to prevent drug accumulation and toxicity (tendon rupture, QT
prolongation, neurotoxicity). The dose should be reduced to 250 mg every 12 hours or
the interval extended to 500 mg every 24 hours. This adjustment maintains therapeutic
drug levels while preventing accumulation. Option A is incorrect and dangerous for
renally-eliminated drugs in CKD. Option C is incorrect because CKD does not decrease
absorption. Option D is unnecessary and does not address the elimination problem.
Q6: A nurse is preparing to administer morphine 4 mg IV to a 78-year-old patient. The
patient weighs 50 kg and has mild renal impairment. Based on pharmacokinetic and
pharmacodynamic principles, what is the nurse's priority consideration?
A. Administer the full dose as ordered; age does not affect opioid dosing
B. Reduce the dose by 25-50% due to decreased clearance and increased brain
sensitivity in elderly patients
C. Administer IM instead of IV to slow absorption and reduce risk
D. Hold the dose until renal function normalizes
Correct Answers with Complete Solutions | Nursing
Competency Assessment | Pass Guaranteed - A+ Graded
Domain 1: Pharmacokinetics & Pharmacodynamics (12 Questions)
Q1: A 68-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. The
nurse reviews the patient's laboratory results and notes a serum potassium level of 3.2
mEq/L and a digoxin level of 1.8 ng/mL. Based on pharmacokinetic principles, what is
the nurse's priority action?
A. Administer the digoxin as ordered since the level is within therapeutic range
B. Hold the digoxin and notify the provider due to hypokalemia increasing digoxin
toxicity risk
C. Administer potassium supplements and give the digoxin
D. Request a repeat digoxin level before administration
Correct Answer: B
Rationale: Hypokalemia (K+ < 3.5 mEq/L) significantly increases the risk of digoxin
toxicity because potassium and digoxin compete for binding sites on the
Na+/K+-ATPase pump. When potassium levels are low, digoxin binds more readily to
these sites, increasing its pharmacodynamic effects and toxicity risk (arrhythmias,
nausea, visual disturbances). Although the digoxin level of 1.8 ng/mL is within the
therapeutic range (0.5-2.0 ng/mL), the concurrent hypokalemia creates a dangerous
situation. The nurse must hold the dose and notify the provider immediately. Option A is
incorrect because therapeutic levels do not guarantee safety when electrolyte
imbalances exist. Option C is incorrect because the nurse should not administer digoxin
without provider notification and correction of the hypokalemia. Option D delays
necessary intervention.
,Q2: A patient receiving IV gentamicin for a severe infection has the following
pharmacokinetic parameters: peak level 12 mcg/mL (drawn 30 minutes after infusion),
trough level 3 mcg/mL (drawn immediately before next dose). The therapeutic range for
gentamicin is peak 5-10 mcg/mL and trough <2 mcg/mL. What is the appropriate
nursing action?
A. Continue the current dosing regimen as ordered
B. Hold the next dose and notify the provider of elevated peak and trough levels
C. Administer the next dose immediately to maintain therapeutic levels
D. Request a repeat trough level before the next administration
Correct Answer: B
Rationale: Both the peak (12 mcg/mL) and trough (3 mcg/mL) levels exceed the
therapeutic ranges for gentamicin. Elevated peak levels increase the risk of
nephrotoxicity, while elevated trough levels indicate drug accumulation and increased
risk of both nephrotoxicity and ototoxicity. Aminoglycosides exhibit
concentration-dependent killing but require careful monitoring due to their narrow
therapeutic index. The nurse must hold the next dose and notify the provider
immediately to prevent permanent renal and auditory damage. Option A is incorrect
because continuing the current regimen will worsen toxicity. Option C is dangerous and
will further increase drug levels. Option D delays necessary intervention when clear
evidence of accumulation exists.
Q3: A nurse is educating a patient prescribed warfarin 5 mg daily. The patient asks why
they need to avoid eating large amounts of spinach and kale. Based on
pharmacodynamic principles, what is the nurse's best response?
A. "These foods contain vitamin K, which antagonizes warfarin's mechanism of action
and can decrease its effectiveness."
B. "These foods are high in fiber, which decreases warfarin absorption from the GI tract."
C. "These foods contain calcium, which binds to warfarin and prevents its absorption."
,D. "These foods increase your metabolism, causing warfarin to be eliminated too
quickly."
Correct Answer: A
Rationale: Warfarin is a vitamin K antagonist that inhibits the synthesis of vitamin
K-dependent clotting factors (II, VII, IX, X). Vitamin K is a fat-soluble vitamin abundant in
leafy green vegetables (spinach, kale, broccoli). Consuming large amounts of vitamin
K-rich foods provides additional substrate for clotting factor synthesis, antagonizing
warfarin's pharmacodynamic effects and potentially decreasing INR, increasing
thrombosis risk. Patients should maintain consistent vitamin K intake rather than
avoiding it completely. Option B is incorrect because fiber does not significantly affect
warfarin absorption. Option C is incorrect because calcium does not bind warfarin.
Option D is incorrect because these foods do not induce warfarin metabolism.
Q4: A 45-year-old patient with liver cirrhosis is prescribed lorazepam 2 mg PO for
anxiety. The nurse recognizes that this patient is at increased risk for drug toxicity. What
pharmacokinetic principle explains this risk?
A. Decreased drug absorption due to portal hypertension
B. Decreased hepatic metabolism leading to prolonged drug half-life and accumulation
C. Increased renal excretion of the active drug compound
D. Increased volume of distribution due to decreased plasma proteins
Correct Answer: B
Rationale: Lorazepam undergoes hepatic metabolism via glucuronidation. In liver
cirrhosis, hepatocellular damage reduces metabolic enzyme function, decreasing drug
metabolism and prolonging half-life. This leads to drug accumulation and increased risk
of sedation, respiratory depression, and coma. While Option D (increased volume of
distribution due to decreased albumin) occurs in liver disease, it primarily affects highly
protein-bound drugs. Lorazepam is relatively less protein-bound compared to other
benzodiazepines. The primary concern is decreased metabolism. Option A is incorrect
, because absorption is not significantly affected. Option C is incorrect because renal
excretion is not increased.
Q5: A patient with chronic kidney disease (CrCl 25 mL/min) is prescribed ciprofloxacin
500 mg PO twice daily for a urinary tract infection. The usual dose is 500 mg every 12
hours. What adjustment should the nurse anticipate?
A. No adjustment needed; administer as prescribed
B. Reduced dose to 250 mg every 12 hours or extended interval to 500 mg every 24
hours
C. Increased dose to 750 mg every 12 hours due to decreased absorption
D. Change to IV administration to ensure adequate drug levels
Correct Answer: B
Rationale: Ciprofloxacin is primarily eliminated unchanged by the kidneys
(approximately 50-70%). In chronic kidney disease with CrCl <30 mL/min, dosage
adjustment is required to prevent drug accumulation and toxicity (tendon rupture, QT
prolongation, neurotoxicity). The dose should be reduced to 250 mg every 12 hours or
the interval extended to 500 mg every 24 hours. This adjustment maintains therapeutic
drug levels while preventing accumulation. Option A is incorrect and dangerous for
renally-eliminated drugs in CKD. Option C is incorrect because CKD does not decrease
absorption. Option D is unnecessary and does not address the elimination problem.
Q6: A nurse is preparing to administer morphine 4 mg IV to a 78-year-old patient. The
patient weighs 50 kg and has mild renal impairment. Based on pharmacokinetic and
pharmacodynamic principles, what is the nurse's priority consideration?
A. Administer the full dose as ordered; age does not affect opioid dosing
B. Reduce the dose by 25-50% due to decreased clearance and increased brain
sensitivity in elderly patients
C. Administer IM instead of IV to slow absorption and reduce risk
D. Hold the dose until renal function normalizes
