Febrile Seizures

There is a 2-5% risk of febrile seizures in typical children. [Baumann: 2000] Characteristics of a simple febrile seizure include: [Subcommittee: 2011]
  • The seizure occurs in a child who is normally developing, without underlying neurologic problems, evidence of meningitis or encephalitis, or metabolic disturbances.
  • The child is 6 months to 5 years of age.
  • The fever is present before or with the seizure.
  • The seizure is generalized, involving arms and legs.
  • There is only 1 seizure in 24 hours.
  • The seizure lasts less than 15 minutes.
Children with complex febrile seizures have a different prognosis and treatment than those with simple febrile seizures. If the seizure has any of the following features, it is a complex febrile seizure:
  • Focal features
  • Prolonged (greater than 15 minutes)
  • Recurs within 24 hours of a first febrile seizure
  • Occurs in a child with a history of afebrile seizures
  • Occurs in a child with a prior neurological insult
  • Occurs in a child with an abnormal baseline neurologic exam

Diagnosis

In the clinical setting of a simple febrile seizure (i.e., a child with the appropriate history and normal exam), brain imaging, blood studies (CBC, electrolytes, calcium, phosphorus, magnesium, glucose), and EEG are not thought to be necessary for children over a year of age.
The American Academy of Pediatrics (AAP) recommends that a lumbar puncture strongly be considered in children:
  • <12 months old
  • With any sign of intracranial infection, such as neck stiffness or Kernig and Brudzinski signs
  • That might have been pre-treated with antibiotics
The AAP also recommends that a lumbar puncture be considered in children from 12 to 18 months as meningeal signs might be difficult to appreciate in this age group. [Subcommittee: 2011] The risk for meningitis in a child with a simple febrile seizure is low [Guedj: 2015] and may be more related to genetics than illness. [Kimia: 2015]

Treatment

Treatment of the fever by acetaminophen or ibuprofen does not prevent the reoccurrence of febrile seizures. [Pavlidou: 2006] Although a continuous course of antiepileptic medications might be effective in decreasing febrile seizure recurrence, febrile seizures do not warrant the potential toxicities of these medications. Treatment doesn't appear to improve long-term outcome in febrile seizures and outcome is good without medical intervention. Although evidence is lacking, a prescription for rectal diazepam or nasal midazolam is sometimes given for home use in children with prolonged, frequent febrile seizures. [Kimia: 2015]

See [Subcommittee: 2011] and [Kimia: 2015].

Prognosis

Simple febrile seizures are benign and have an excellent prognosis; the child is unlikely to have developmental problems or future epilepsy. Treatment does not appear to improve long-term outcomes and good outcomes are expected.

The risk of epilepsy for all children is 1%; having febrile seizures increases this either not at all or only minimally to 2.4% [Annegers: 1987] or 6% [Vestergaard: 2007]. Children who are younger than 12 months or who have a family history of epilepsy appear to be in the higher risk range.

Recurrence risk for future febrile seizures is 50% for children under 1 year of age, 30% for children over 1 year, and 50% for children who have experienced 2 febrile seizures (not given by age range).

Resources

Practice Guidelines

Subcommittee on febrile seizures.
Neurodiagnostic evaluation of the child with a simple febrile seizure.
Pediatrics. 2011;127(2):389-94. PubMed abstract

Helpful Articles

PubMed search for articles on Febrile Seizures in children for the last 3 years.

Capovilla G, Mastrangelo M, Romeo A, Vigevano F.
Recommendations for the management of "febrile seizures": Ad Hoc Task Force of LICE Guidelines Commission.
Epilepsia. 2009;50 Suppl 1:2-6. PubMed abstract

Mohebbi MR, Holden KR, Butler IJ.
FIRST: a practical approach to the causes and management of febrile seizures.
J Child Neurol. 2008;23(12):1484-8. PubMed abstract

Authors & Reviewers

Last update/revision: January 2019
Current Authors and Reviewers:
Authors: Lynne M. Kerr, MD, PhD

Page Bibliography

Annegers JF, Hauser WA, Shirts SB, Kurland LT.
Factors prognostic of unprovoked seizures after febrile convulsions.
N Engl J Med. 1987;316(9):493-8. PubMed abstract

Baumann RJ, Duffner PK.
Treatment of children with simple febrile seizures: the AAP practice parameter. American Academy of Pediatrics.
Pediatr Neurol. 2000;23(1):11-7. PubMed abstract

Guedj R, Chappuy H, Titomanlio L, Trieu TV, Biscardi S, Nissack-Obiketeki G, Pellegrino B, Charara O, Angoulvant F, Villemeur TB, Levy C, Cohen R, Armengaud JB, Carbajal R.
Risk of Bacterial Meningitis in Children 6 to 11 Months of Age With a First Simple Febrile Seizure: A Retrospective, Cross-sectional, Observational Study.
Acad Emerg Med. 2015;22(11):1290-7. PubMed abstract

Kimia AA, Bachur RG, Torres A, Harper MB.
Febrile seizures: emergency medicine perspective.
Curr Opin Pediatr. 2015;27(3):292-7. PubMed abstract

Pavlidou E, Tzitiridou M, Panteliadis C.
Effectiveness of intermittent diazepam prophylaxis in febrile seizures: long-term prospective controlled study.
J Child Neurol. 2006;21(12):1036-40. PubMed abstract

Subcommittee on febrile seizures.
Neurodiagnostic evaluation of the child with a simple febrile seizure.
Pediatrics. 2011;127(2):389-94. PubMed abstract

Vestergaard M, Pedersen CB, Sidenius P, Olsen J, Christensen J.
The Long-Term Risk of Epilepsy after Febrile Seizures in Susceptible Subgroups.
Am J Epidemiol. 2007. PubMed abstract