Sign Up for a Free Account
  • Updated 01.23.2024
  • Released 10.18.1993
  • Expires For CME 01.23.2027

Febrile seizures



Febrile seizures are a common pediatric phenomenon and are typically associated with a benign outcome. The genetic basis and pathogenesis of this syndrome remain under intense investigation. Evidence-based guidelines suggest minimal investigations are needed for diagnosis, and most children require neither intermittent nor long-term treatment. This clinical article includes summaries from the results of the multicenter study entitled “Consequences of Prolonged Febrile Seizures in Childhood,” or the FEBSTAT study.

Key points

• Febrile seizures are the most common pediatric seizure type, affecting 3% to 4% of all children.

• Although many affected children have recurrent febrile seizures, there is low risk of developing epilepsy.

• The American Academy of Pediatrics offers guidelines for the evaluation and management of children with febrile seizures. More information can be accessed at the following website: American Academy of Pediatrics.

Historical note and terminology

Febrile seizures (febrile convulsions) are the most common convulsive events in the human experience. They were recognized as distinct from other seizures in the mid-19th century, and at that time treatment was redirected to the underlying causes of fever rather than the symptom of a seizure. With the introduction of the thermometer at the end of the 1800s, fever was understood to be the primary factor producing the convulsion. Until the early 20th century, infantile convulsions were thought to be severe and often fatal, with few available effective treatments. Sentinel studies in the 1940s by Lennox and Livingston investigated risk factors for recurrence and later epilepsy (124; 120).

In the 1970s, two population-based studies formed the foundation of the current view of febrile seizures (207; 54): they are common, many recur, developmental outcome is not altered, and few children later develop epilepsy. In 2008 and 2011, updated evidence-based practice parameters were published by the American Academy of Pediatrics Committee on Quality Improvement, Subcommittee on Febrile Seizures (06). This, along with the original 1996 publication, and a consensus statement by the International League Against Epilepsy (30), reflects the current evidence for diagnosis, and treatment recommendations for febrile seizures (05; 06).

Studies conducted in the United States and Denmark reported that about 3% to 4% of all children will have at least one febrile seizure (142; 217). However, febrile seizures may be more common in other countries. For example, a longitudinal study of 54,233 children in Korea reported a prevalence of 11.19% (38). Although the seizures are associated with fever (greater than 38°C by rectal or tympanic membrane measurement), those provoked by central nervous system (CNS) infection are excluded. The peak age for febrile seizures is about 2 years of age with a range between about 6 months and 5 years (04; 38).

Table 1. Febrile Seizure Types

Simple febrile seizures

Complex febrile seizures

Must include the following:

Any one of the following:

• One in 24 hours

• More than one in 24 hours

• 15 minutes or less in duration

• More than 15 minutes in duration

• Generalized tonic-clonic semiology

• Focality in seizure semiology

Febrile seizures are generally thought to be benign, with only 2% to 6% of affected children later developing epilepsy (142; 49). Simple febrile seizures carry a subsequent epilepsy risk of 2%, whereas complex febrile seizures have a 5% to 10% risk. As such, febrile seizures can be viewed as a syndrome of acute symptomatic seizures rather than as a true epilepsy syndrome (56).

This is an article preview.
Start a Free Account
to access the full version.

  • Nearly 3,000 illustrations, including video clips of neurologic disorders.

  • Every article is reviewed by our esteemed Editorial Board for accuracy and currency.

  • Full spectrum of neurology in 1,200 comprehensive articles.

  • Listen to MedLink on the go with Audio versions of each article.

Questions or Comment?

MedLink®, LLC

3525 Del Mar Heights Rd, Ste 304
San Diego, CA 92130-2122

Toll Free (U.S. + Canada): 800-452-2400

US Number: +1-619-640-4660



ISSN: 2831-9125