Febrile Seizures


  • Occur in 2-3% of children, following respiratory, GI or urinary tract infections
  • Simple: single, brief (<15minutes), generalized during fever (>38) in developmentally and neurologically normal children between 6mo and 5yr without intracranial infection or other cause
  • Complex: febrile seizure that lasts longer than 15 minutes, is focal or that recurs within 24hr

Differential diagnosis

  • Eplilepsy
  • CNS infection
  • Anoxia/stroke/bleed
  • Trauma
  • Intoxication
  • Metabolic encephalopathy
  • Neurodegenerative disorder
  • Brain tumor
  • Neurocutaneous syndromes
  • Previous brain injury


  • Seizure: length, description
  • Previous history of seizures (febrile or afebrile) – 1/3 of children with one simple febrile seizure will have another
  • Precipitating factors: height and duration of fever, length and symptoms of preceding illness, head trauma, possibility of ingestion
  • Past medical history: gestation, birth, general health, growth and development
  • Risk factors: Family history, slow milestones, Roseola/Shigella, DTP and measles vaccinations, males>females
  • Neurological findings: H/A, vomiting, lethargy, weakness, sensory deficits, change in vision/behaviour/balance/gait

Physical exam – rule out meningitis, look for focus of infection

  • Vitals, head circumference
  • HEENT (meningismus)
  • Neurologic (papilledema)
  • Standard physical exam


  • CBCD, lytes, Ca, glucose, toxicology
  • Lumbar puncture (<18 months)
  • EEG (once well, will be normal if typical… must do if atypical)
  • MRI


  • Not indicated as only 1/3 will proceed to have another febrile seizure – majority of which will occur within 1 year of seizure
  • Increased recurrence risk if complex, family history, low fever with seizure
  • If typical no long-term adverse consequences
  • Rarely lead to epilepsy or recurrent non-febrile seizures later in life (1-2.4%), increased risk compared to general population
  • Anticonvulsants prophylaxis (underlying neurological condition)
  • Anticonvulsants:
    • Diazepam PO/PR
  • For parents: antipyretics, first aid instructions, when to seek help (ER)
    • No cold baths as they increase core body temperature

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