Which statement most accurately describes a symptom not expected in phenytoin overdose?

Which statement most accurately describes a symptom not expected in phenytoin overdose?

• A. Hypoglycaemia
• B. Drowsiness
• C. Nystagmus
• D. Ataxia

Answer: (A)

Phenytoin overdose most clearly shows neurologic toxicity due to central nervous system depression and cerebellar/vestibular involvement. Drowsiness reflects generalized CNS depression, while nystagmus indicates disturbance of ocular motor control from brainstem/cerebellar effects. Ataxia arises from impaired cerebellar function, which is a common sign as the drug toxicity progresses. Hypoglycaemia, on the other hand, is a metabolic issue related to glucose regulation and not a typical consequence of phenytoin toxicity. Therefore, low blood glucose is not expected with phenytoin overdose, making it the best description of a symptom not typically seen in this context.

Phenytoin overdose most clearly shows neurologic toxicity due to central nervous system depression and cerebellar/vestibular involvement. Drowsiness reflects generalized CNS depression, while nystagmus indicates disturbance of ocular motor control from brainstem/cerebellar effects. Ataxia arises from impaired cerebellar function, which is a common sign as the drug toxicity progresses. Hypoglycaemia, on the other hand, is a metabolic issue related to glucose regulation and not a typical consequence of phenytoin toxicity. Therefore, low blood glucose is not expected with phenytoin overdose, making it the best description of a symptom not typically seen in this context.