NCLEX-RN Pharmacology Infection Exam
Questions |
Antibiotics, Antifungals & Antivirals Practice
Test Bank (20 Original MCQs with Rationales)
Question 1
Clinical Scenario
A 76-year-old male resident of a long-term care facility is
prescribed ciprofloxacin 500 mg twice daily for a complicated
urinary tract infection. The nurse reviews the client's
medication administration record and notes he also takes
warfarin 5 mg daily for atrial fibrillation. The client's current INR
is 3.8, which is above his target range of 2.0-3.0.
Question Stem
Which action should the nurse take first?
A. Administer the ciprofloxacin as scheduled and continue to
monitor the INR.
B. Administer vitamin K 2.5 mg orally to reverse the elevated
INR.
,C. Hold the ciprofloxacin and notify the healthcare provider of
the elevated INR.
D. Hold the warfarin and administer the ciprofloxacin as
ordered.
Correct Answer: D. Hold the warfarin and administer the
ciprofloxacin as ordered.
Detailed Rationale
The correct answer is to hold the warfarin and administer the
ciprofloxacin, then notify the healthcare provider.
Fluoroquinolones like ciprofloxacin can significantly potentiate
the effects of warfarin through two mechanisms: they eliminate
vitamin K-producing intestinal flora, reducing the body's natural
source of vitamin K needed for clotting factor synthesis, and
they inhibit hepatic CYP450 enzymes that metabolize warfarin .
The elevated INR of 3.8 indicates that the client is already
supratherapeutic and at increased risk for bleeding.
Administering ciprofloxacin without adjusting the warfarin dose
could push the INR dangerously higher . The nurse should hold
the warfarin, administer the antibiotic to treat the infection,
and promptly notify the provider for warfarin dose adjustment
recommendations.
,Option A is incorrect because administering both medications
without intervention would further elevate the INR and
increase bleeding risk. Option B is incorrect because
administering vitamin K prophylactically is not the standard of
care for an asymptomatic INR elevation of 3.8 and could reverse
anticoagulation too quickly, potentially causing a
thromboembolic event. Option C is incorrect because holding
the antibiotic would delay treatment of the UTI in this elderly
patient and does not address the underlying drug interaction
mechanism. The priority nursing action is to manage the
immediate drug interaction risk while ensuring the infection is
treated.
Learning Objective
After completing this question, the learner should be able to:
• Explain the mechanism of interaction between
fluoroquinolones and warfarin.
• Prioritize nursing actions when a drug interaction places a
client at risk.
• Identify an elevated INR as a potential adverse outcome
requiring clinical intervention.
Medication Safety Focus: Drug Interaction
Question 2
, Clinical Scenario
A 32-year-old female client is admitted to the emergency
department with a fever of 102.2°F, chills, headache, and
photophobia. A lumbar puncture confirms bacterial meningitis,
and the provider orders vancomycin 1.5 g IV every 12 hours.
The client's baseline serum creatinine is 1.1 mg/dL. The nurse
prepares to infuse the first dose of vancomycin. After 20
minutes, the client reports intense itching on her face and neck,
and the nurse observes flushing of the upper body.
Question Stem
Which action should the nurse take next?
A. Slow the IV infusion rate and continue to monitor the client.
B. Stop the infusion and administer diphenhydramine 25 mg IV.
C. Continue the infusion at the prescribed rate and document
the findings.
D. Reassure the client that this is a normal vancomycin reaction.
Correct Answer: A. Slow the IV infusion rate and continue to
monitor the client.
Detailed Rationale
The correct answer is to slow the IV infusion rate and continue
monitoring. The client is experiencing Red Man Syndrome
Questions |
Antibiotics, Antifungals & Antivirals Practice
Test Bank (20 Original MCQs with Rationales)
Question 1
Clinical Scenario
A 76-year-old male resident of a long-term care facility is
prescribed ciprofloxacin 500 mg twice daily for a complicated
urinary tract infection. The nurse reviews the client's
medication administration record and notes he also takes
warfarin 5 mg daily for atrial fibrillation. The client's current INR
is 3.8, which is above his target range of 2.0-3.0.
Question Stem
Which action should the nurse take first?
A. Administer the ciprofloxacin as scheduled and continue to
monitor the INR.
B. Administer vitamin K 2.5 mg orally to reverse the elevated
INR.
,C. Hold the ciprofloxacin and notify the healthcare provider of
the elevated INR.
D. Hold the warfarin and administer the ciprofloxacin as
ordered.
Correct Answer: D. Hold the warfarin and administer the
ciprofloxacin as ordered.
Detailed Rationale
The correct answer is to hold the warfarin and administer the
ciprofloxacin, then notify the healthcare provider.
Fluoroquinolones like ciprofloxacin can significantly potentiate
the effects of warfarin through two mechanisms: they eliminate
vitamin K-producing intestinal flora, reducing the body's natural
source of vitamin K needed for clotting factor synthesis, and
they inhibit hepatic CYP450 enzymes that metabolize warfarin .
The elevated INR of 3.8 indicates that the client is already
supratherapeutic and at increased risk for bleeding.
Administering ciprofloxacin without adjusting the warfarin dose
could push the INR dangerously higher . The nurse should hold
the warfarin, administer the antibiotic to treat the infection,
and promptly notify the provider for warfarin dose adjustment
recommendations.
,Option A is incorrect because administering both medications
without intervention would further elevate the INR and
increase bleeding risk. Option B is incorrect because
administering vitamin K prophylactically is not the standard of
care for an asymptomatic INR elevation of 3.8 and could reverse
anticoagulation too quickly, potentially causing a
thromboembolic event. Option C is incorrect because holding
the antibiotic would delay treatment of the UTI in this elderly
patient and does not address the underlying drug interaction
mechanism. The priority nursing action is to manage the
immediate drug interaction risk while ensuring the infection is
treated.
Learning Objective
After completing this question, the learner should be able to:
• Explain the mechanism of interaction between
fluoroquinolones and warfarin.
• Prioritize nursing actions when a drug interaction places a
client at risk.
• Identify an elevated INR as a potential adverse outcome
requiring clinical intervention.
Medication Safety Focus: Drug Interaction
Question 2
, Clinical Scenario
A 32-year-old female client is admitted to the emergency
department with a fever of 102.2°F, chills, headache, and
photophobia. A lumbar puncture confirms bacterial meningitis,
and the provider orders vancomycin 1.5 g IV every 12 hours.
The client's baseline serum creatinine is 1.1 mg/dL. The nurse
prepares to infuse the first dose of vancomycin. After 20
minutes, the client reports intense itching on her face and neck,
and the nurse observes flushing of the upper body.
Question Stem
Which action should the nurse take next?
A. Slow the IV infusion rate and continue to monitor the client.
B. Stop the infusion and administer diphenhydramine 25 mg IV.
C. Continue the infusion at the prescribed rate and document
the findings.
D. Reassure the client that this is a normal vancomycin reaction.
Correct Answer: A. Slow the IV infusion rate and continue to
monitor the client.
Detailed Rationale
The correct answer is to slow the IV infusion rate and continue
monitoring. The client is experiencing Red Man Syndrome
