What is the recommended approach for starting medication in a pediatric patient with an undiagnosed seizure?

Approach to Starting Medication for Undiagnosed Seizure in Pediatric Patients

For pediatric patients with an undiagnosed seizure, medication should generally NOT be initiated after a first unprovoked seizure unless specific risk factors are present. 1

Initial Assessment and Diagnostic Considerations

• Determine if the seizure was provoked or unprovoked, as this significantly impacts treatment decisions 2
• Evaluate for precipitating factors such as fever, trauma, drug exposure, or metabolic abnormalities that may have triggered the seizure 2
• Consider age-specific risk factors:
  • Infants <6 months with seizures require immediate emergency medical attention 2
  • Children with febrile seizures (common between 6 months and 2 years) typically do not require antiseizure medication 2

Diagnostic Workup Before Medication Decisions

• EEG is recommended as part of the neurodiagnostic evaluation for all children with an apparent first unprovoked seizure 2
• Neuroimaging considerations:
  • MRI is the preferred modality if neuroimaging is obtained 2
  • Emergent neuroimaging should be performed in children with postictal focal deficits that don't quickly resolve 2
  • Consider non-urgent MRI for children with cognitive/motor impairment, abnormal neurological exam, partial onset seizures, or age <1 year 2
• Laboratory tests should be ordered based on clinical circumstances (dehydration, vomiting, altered mental status) 2
• Toxicology screening should be considered if drug exposure is suspected 2

Risk Assessment for Recurrence

• Approximately one-third to one-half of patients with a first unprovoked seizure will have a recurrent seizure within 5 years 1
• Early seizure recurrence is common, with 85% of early recurrences happening within 6 hours of the first seizure 1
• Risk factors that increase recurrence probability include:
  • Remote history of brain disease or injury 2
  • Abnormal EEG findings 3
  • Focal seizure onset 2

Medication Initiation Guidelines

• For first unprovoked seizure without evidence of brain disease/injury:

  • Antiepileptic medication is generally NOT recommended 2, 1
  • The number needed to treat to prevent a single seizure recurrence within 2 years is approximately 14 patients 1
  • Treatment may prolong time to subsequent seizure but doesn't affect 5-year outcomes 2

• For first unprovoked seizure WITH evidence of brain disease/injury:

  • Antiepileptic medication may be initiated due to higher recurrence risk 2
  • This includes patients with history of stroke, trauma, tumor, or other CNS disease 2

• For provoked seizures:

  • Identify and treat the precipitating medical condition rather than starting antiepileptic medication 2
  • For example, correct electrolyte abnormalities if present 2

• For recurrent unprovoked seizures:

  • Antiepileptic medication is recommended as risk increases substantially from about one-third to about three-quarters of patients having another seizure within 5 years 2

Medication Selection When Treatment Is Indicated

• For children 4-16 years with partial onset seizures:

  • Levetiracetam: Initial dose of 10 mg/kg twice daily (20 mg/kg/day), increasing every 2 weeks to target dose of 60 mg/kg/day 4
  • Oxcarbazepine: Initial dose of 8-10 mg/kg/day (not exceeding 600 mg/day) given twice daily, increasing to target maintenance dose based on weight 5

• For children 2-4 years:

  • Levetiracetam: Similar dosing as above, but may require higher per-weight dosing 4
  • Oxcarbazepine: Initial dose of 8-10 mg/kg/day, with maximum maintenance dose not exceeding 60 mg/kg/day in a twice-daily regimen 5

Monitoring and Follow-up

• Patients should be observed during the highest risk period for early recurrence (first 6 hours after seizure) 1
• For patients started on medication, monitor for side effects and therapeutic response 4, 5
• If medication is deferred, educate parents/caregivers about seizure first aid and when to seek emergency care 2

Special Considerations

• Febrile seizures: Antipyretics (acetaminophen, ibuprofen) are not effective for stopping seizures or preventing subsequent febrile seizures 2
• Neonatal seizures require specialized management with phenobarbital typically used as first-line therapy 6
• Regional new-onset seizure clinics can provide efficient, timely diagnosis and appropriate evaluation/treatment 7