NCLEX-RN Pharmacology Neurological System
Part 2 Practice Questions with Detailed
Rationales |
20 Original Nursing Exam-Style MCQs |
ATI & NGN Inspired Study Guide
Question 1
Clinical Scenario
A 45-year-old male with a history of a seizure disorder is
admitted to the medical-surgical unit. He has been taking
phenytoin 300 mg daily. His morning phenytoin serum level
returns at 22 mcg/mL. Upon assessment, the nurse notes the
patient has new-onset nystagmus, mild ataxia, and slightly
slurred speech. His vital signs are stable.
Question Stem
Which action should the nurse take first?
A. Administer the scheduled morning dose of phenytoin to
maintain therapeutic levels.
,B. Hold the medication and notify the healthcare provider
immediately.
C. Initiate a different antiepileptic medication to prevent further
seizures.
D. Assess the patient for signs of a localized infection at the IV
site.
Correct Answer
Correct Answer: B. Hold the medication and notify the
healthcare provider immediately.
Detailed Rationale
The therapeutic serum range for phenytoin is 10 to 20 mcg/mL.
A level of 22 mcg/mL indicates mild to moderate toxicity. Early
clinical manifestations of phenytoin toxicity include nystagmus,
ataxia, slurred speech, and lethargy. The priority nursing action
is to hold the medication and notify the healthcare provider
immediately to prevent progression to severe toxicity, which
can include coma or respiratory depression. Administering the
next scheduled dose would exacerbate the toxicity and is
unsafe. Initiating a different antiepileptic medication without a
specific provider prescription violates nursing scope of practice
and could cause dangerous drug interactions. While assessing
for infection is a standard nursing action, it does not address
the acute, life-threatening physiological imbalance indicated by
the toxic drug level and corresponding neurological symptoms.
,The nurse must also implement fall precautions due to the
patient's ataxia. Patient teaching should include the importance
of regular blood draws to monitor therapeutic levels and
reporting any new neurological symptoms promptly.
Learning Objective
• Identify the therapeutic range and early signs of phenytoin
toxicity.
• Prioritize nursing interventions for abnormal antiepileptic
drug levels.
• Implement safety measures for patients experiencing
medication-induced ataxia.
Medication Safety Focus
Monitoring
Question 2
Clinical Scenario
An 8-year-old child is being treated for a seizure disorder with
valproic acid. Over the past two days, the parents report the
child has developed new-onset nausea, vomiting, and unusual
lethargy. Laboratory results reveal significantly elevated alanine
aminotransferase (ALT) and aspartate aminotransferase (AST)
levels compared to baseline.
, Question Stem
How should the nurse interpret these findings?
A. The child is experiencing a common, self-limiting viral
gastrointestinal illness.
B. The valproic acid dose is too low and should be increased to
control seizures.
C. The child is exhibiting signs of potential hepatotoxicity
requiring immediate provider notification.
D. The symptoms indicate an expected, harmless side effect of
valproic acid therapy.
Correct Answer
Correct Answer: C. The child is exhibiting signs of potential
hepatotoxicity requiring immediate provider notification.
Detailed Rationale
Valproic acid carries a Black Box Warning for hepatotoxicity,
especially in children under 2 years of age, though the risk
remains in older children. Symptoms like nausea, vomiting,
lethargy, and elevated liver enzymes (ALT/AST) are critical red
flags. The nurse must recognize this as potential hepatotoxicity
and notify the provider immediately for medication
discontinuation and further diagnostic workup. Attributing
these symptoms to a viral illness delays critical, life-saving
intervention. Increasing the dose would worsen liver damage
and is contraindicated. Administering an antiemetic masks the
Part 2 Practice Questions with Detailed
Rationales |
20 Original Nursing Exam-Style MCQs |
ATI & NGN Inspired Study Guide
Question 1
Clinical Scenario
A 45-year-old male with a history of a seizure disorder is
admitted to the medical-surgical unit. He has been taking
phenytoin 300 mg daily. His morning phenytoin serum level
returns at 22 mcg/mL. Upon assessment, the nurse notes the
patient has new-onset nystagmus, mild ataxia, and slightly
slurred speech. His vital signs are stable.
Question Stem
Which action should the nurse take first?
A. Administer the scheduled morning dose of phenytoin to
maintain therapeutic levels.
,B. Hold the medication and notify the healthcare provider
immediately.
C. Initiate a different antiepileptic medication to prevent further
seizures.
D. Assess the patient for signs of a localized infection at the IV
site.
Correct Answer
Correct Answer: B. Hold the medication and notify the
healthcare provider immediately.
Detailed Rationale
The therapeutic serum range for phenytoin is 10 to 20 mcg/mL.
A level of 22 mcg/mL indicates mild to moderate toxicity. Early
clinical manifestations of phenytoin toxicity include nystagmus,
ataxia, slurred speech, and lethargy. The priority nursing action
is to hold the medication and notify the healthcare provider
immediately to prevent progression to severe toxicity, which
can include coma or respiratory depression. Administering the
next scheduled dose would exacerbate the toxicity and is
unsafe. Initiating a different antiepileptic medication without a
specific provider prescription violates nursing scope of practice
and could cause dangerous drug interactions. While assessing
for infection is a standard nursing action, it does not address
the acute, life-threatening physiological imbalance indicated by
the toxic drug level and corresponding neurological symptoms.
,The nurse must also implement fall precautions due to the
patient's ataxia. Patient teaching should include the importance
of regular blood draws to monitor therapeutic levels and
reporting any new neurological symptoms promptly.
Learning Objective
• Identify the therapeutic range and early signs of phenytoin
toxicity.
• Prioritize nursing interventions for abnormal antiepileptic
drug levels.
• Implement safety measures for patients experiencing
medication-induced ataxia.
Medication Safety Focus
Monitoring
Question 2
Clinical Scenario
An 8-year-old child is being treated for a seizure disorder with
valproic acid. Over the past two days, the parents report the
child has developed new-onset nausea, vomiting, and unusual
lethargy. Laboratory results reveal significantly elevated alanine
aminotransferase (ALT) and aspartate aminotransferase (AST)
levels compared to baseline.
, Question Stem
How should the nurse interpret these findings?
A. The child is experiencing a common, self-limiting viral
gastrointestinal illness.
B. The valproic acid dose is too low and should be increased to
control seizures.
C. The child is exhibiting signs of potential hepatotoxicity
requiring immediate provider notification.
D. The symptoms indicate an expected, harmless side effect of
valproic acid therapy.
Correct Answer
Correct Answer: C. The child is exhibiting signs of potential
hepatotoxicity requiring immediate provider notification.
Detailed Rationale
Valproic acid carries a Black Box Warning for hepatotoxicity,
especially in children under 2 years of age, though the risk
remains in older children. Symptoms like nausea, vomiting,
lethargy, and elevated liver enzymes (ALT/AST) are critical red
flags. The nurse must recognize this as potential hepatotoxicity
and notify the provider immediately for medication
discontinuation and further diagnostic workup. Attributing
these symptoms to a viral illness delays critical, life-saving
intervention. Increasing the dose would worsen liver damage
and is contraindicated. Administering an antiemetic masks the
