NCLEX-RN Pharmacology Neurological
System Part 1 Exam Questions &
Answers
20 Original NCLEX NGN Practice MCQs
with Rationales
Nursing Pharmacology Study Guide
Question 1
Clinical Scenario
A 68-year-old man with newly diagnosed focal seizures is
prescribed phenytoin. His medical history includes
hypertension and type 2 diabetes mellitus. Current medications
include lisinopril and metformin. During morning rounds, the
nurse notes that the client has swollen, tender gums and
reports occasional dizziness. His serum phenytoin level is 15
mcg/mL (therapeutic range: 10–20 mcg/mL).
Question Stem
,Which nursing intervention is the highest priority to reduce the
client's risk of future complications while receiving phenytoin
therapy?
A. Encourage meticulous oral hygiene and routine dental
evaluations.
B. Advise the client to stop taking the medication if dizziness
occurs.
C. Restrict dietary protein intake while taking the medication.
D. Instruct the client to take the medication only when seizure
symptoms begin.
Correct Answer
Correct Answer: A. Encourage meticulous oral hygiene and
routine dental evaluations.
Detailed Rationale
Phenytoin is an antiseizure medication that stabilizes neuronal
membranes by slowing sodium channel recovery and
decreasing abnormal electrical activity. One of its well-known
adverse effects is gingival hyperplasia, particularly with long-
term therapy. Because the client's serum drug level is
therapeutic, the swollen gums are most consistent with this
predictable adverse effect rather than toxicity. Excellent oral
hygiene, daily brushing and flossing, and regular dental care
significantly reduce the severity of gingival overgrowth.
,Option B is incorrect because mild dizziness is relatively
common, especially during initiation of therapy. The client
should not discontinue phenytoin abruptly because sudden
withdrawal can precipitate rebound seizures or status
epilepticus. The nurse should instead assess the severity of
symptoms and reinforce safety precautions.
Option C is incorrect because protein restriction has no role in
preventing adverse effects of phenytoin. Maintaining balanced
nutrition is appropriate unless another condition requires
dietary modification.
Option D is incorrect because phenytoin must be taken
consistently to maintain therapeutic serum concentrations. It is
ineffective when taken only during seizure activity because it is
intended for seizure prevention rather than acute treatment.
Patient education should also include avoiding abrupt
discontinuation, reporting rash or fever promptly, avoiding
alcohol unless approved by the provider, and obtaining periodic
serum drug levels and liver function monitoring.
Learning Objectives
After completing this question, the learner should be able to:
• Identify a common long-term adverse effect of phenytoin.
• Implement nursing interventions that reduce medication
complications.
, • Reinforce patient teaching regarding adherence to
antiseizure medications.
• Differentiate therapeutic effects from medication toxicity.
Medication Safety Focus
Patient education
Question 2
Clinical Scenario
A 25-year-old woman with generalized tonic-clonic seizures has
been taking valproic acid for three years. During a follow-up
visit she reports fatigue, persistent nausea, upper abdominal
pain, and dark-colored urine for the past two days. Laboratory
results show elevated AST and ALT levels.
Question Stem
Which nursing action should be taken first?
A. Encourage increased fluid intake throughout the day.
B. Continue administering the medication as prescribed.
C. Notify the healthcare provider immediately and hold the next
dose.
D. Recommend taking the medication with food to decrease
nausea.
System Part 1 Exam Questions &
Answers
20 Original NCLEX NGN Practice MCQs
with Rationales
Nursing Pharmacology Study Guide
Question 1
Clinical Scenario
A 68-year-old man with newly diagnosed focal seizures is
prescribed phenytoin. His medical history includes
hypertension and type 2 diabetes mellitus. Current medications
include lisinopril and metformin. During morning rounds, the
nurse notes that the client has swollen, tender gums and
reports occasional dizziness. His serum phenytoin level is 15
mcg/mL (therapeutic range: 10–20 mcg/mL).
Question Stem
,Which nursing intervention is the highest priority to reduce the
client's risk of future complications while receiving phenytoin
therapy?
A. Encourage meticulous oral hygiene and routine dental
evaluations.
B. Advise the client to stop taking the medication if dizziness
occurs.
C. Restrict dietary protein intake while taking the medication.
D. Instruct the client to take the medication only when seizure
symptoms begin.
Correct Answer
Correct Answer: A. Encourage meticulous oral hygiene and
routine dental evaluations.
Detailed Rationale
Phenytoin is an antiseizure medication that stabilizes neuronal
membranes by slowing sodium channel recovery and
decreasing abnormal electrical activity. One of its well-known
adverse effects is gingival hyperplasia, particularly with long-
term therapy. Because the client's serum drug level is
therapeutic, the swollen gums are most consistent with this
predictable adverse effect rather than toxicity. Excellent oral
hygiene, daily brushing and flossing, and regular dental care
significantly reduce the severity of gingival overgrowth.
,Option B is incorrect because mild dizziness is relatively
common, especially during initiation of therapy. The client
should not discontinue phenytoin abruptly because sudden
withdrawal can precipitate rebound seizures or status
epilepticus. The nurse should instead assess the severity of
symptoms and reinforce safety precautions.
Option C is incorrect because protein restriction has no role in
preventing adverse effects of phenytoin. Maintaining balanced
nutrition is appropriate unless another condition requires
dietary modification.
Option D is incorrect because phenytoin must be taken
consistently to maintain therapeutic serum concentrations. It is
ineffective when taken only during seizure activity because it is
intended for seizure prevention rather than acute treatment.
Patient education should also include avoiding abrupt
discontinuation, reporting rash or fever promptly, avoiding
alcohol unless approved by the provider, and obtaining periodic
serum drug levels and liver function monitoring.
Learning Objectives
After completing this question, the learner should be able to:
• Identify a common long-term adverse effect of phenytoin.
• Implement nursing interventions that reduce medication
complications.
, • Reinforce patient teaching regarding adherence to
antiseizure medications.
• Differentiate therapeutic effects from medication toxicity.
Medication Safety Focus
Patient education
Question 2
Clinical Scenario
A 25-year-old woman with generalized tonic-clonic seizures has
been taking valproic acid for three years. During a follow-up
visit she reports fatigue, persistent nausea, upper abdominal
pain, and dark-colored urine for the past two days. Laboratory
results show elevated AST and ALT levels.
Question Stem
Which nursing action should be taken first?
A. Encourage increased fluid intake throughout the day.
B. Continue administering the medication as prescribed.
C. Notify the healthcare provider immediately and hold the next
dose.
D. Recommend taking the medication with food to decrease
nausea.
