Febrile seizure symptoms can range from mild — staring — to more severe shaking or tightening of the muscles.

A child having a febrile seizure may:

  • Have a fever higher than 100.4 F (38.0 C)
  • Lose consciousness
  • Shake or jerk arms and legs

Febrile seizures are classified as simple or complex:

  • Simple febrile seizures. This more common type lasts from a few seconds to 15 minutes. Simple febrile seizures do not recur within a 24-hour period and are generalized, not specific to one part of the body.
  • Complex febrile seizures. This type lasts longer than 15 minutes, occurs more than once within 24 hours or is confined to one side of your child's body.

Febrile seizures most often occur within 24 hours of the onset of a fever and can be the first sign that a child is ill.

When to see a doctor

See your child's doctor as soon as possible after your child's first febrile seizure, even if it lasts only a few seconds. Call an ambulance to take your child to the emergency room if the seizure lasts longer than 10 minutes or is accompanied by:

  • Vomiting
  • A stiff neck
  • Breathing problems
  • Extreme sleepiness
Dec. 05, 2014

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