Medical Dictionary Search Engines

Please be patient! It may take up to ONE minute to load all the Engines.
Problems? Please contact our support.


Search For


Specialty Search




Other encyclopedia topics: A-Ag Ah-Ap Aq-Az B-Bk Bl-Bz C-Cg Ch-Co Cp-Cz D-Di Dj-Dz E-Ep Eq-Ez F G H-Hf Hg-Hz I-In Io-Iz J K L-Ln Lo-Lz M-Mf Mg-Mz N O P-Pl Pm-Pz Q R S-Sh Si-Sp Sq-Sz T-Tn To-Tz U V W X Y Z 0-9   

Febrile seizures

Alternative names

Seizure - fever induced


A febrile seizure is a convulsion in a child triggered by a fever . Such convulsions occur without any underlying brain or spinal cord infection or other neurologic cause.

Causes, incidence, and risk factors

About 3-5% of otherwise healthy children between the ages of 9 months and 5 years will have a seizure caused by a fever. Toddlers are most commonly affected. There is a tendency for febrile seizures to run in families. Most febrile seizures are triggered by a rapid rise of body temperature over 102.2°F. Most occur well within the first 24 hours of an illness, not necessarily when the fever is highest. The seizure is often the first sign of a fever.

The first febrile seizure is one of life's most frightening moments for parents. Most parents are afraid that their child will die or have brain damage. Thankfully, simple febrile seizures are harmless. There is no evidence that simple febrile seizures cause death, brain damage, epilepsy, mental retardation, a decrease in IQ, or learning difficulties.

Most febrile seizures are triggered by fevers from viral upper respiratory infections, ear infections, or roseola. Meningitis causes less than 0.1% of febrile seizures but should ALWAYS be considered, especially in children less than one year old or those who still look ill when the fever comes down.

A simple febrile seizure stops by itself within a few seconds to 10 minutes, usually followed by a brief period of drowsiness or confusion. Anticonvulsant medicines are generally not needed.

A complex febrile seizure is one that lasts longer than 15 minutes, occurs in an isolated part of the body, or recurs during the same illness.

About a third of children who have had a febrile seizure will have another one with a subsequent fever. Of those who do, about half will have a third seizure. Few children have more than three febrile seizures.

If there is a family history, if the first seizure happened before 12 months of age, or if the seizure happened with a fever below 102, a child is more likely to fall in the group that has more than one febrile seizure.


A febrile seizure may be as mild as the child's eyes rolling or limbs stiffening. Quite often a fever triggers a full-blown convulsion that involves the whole body.

Signs and tests

A febrile seizure may be diagnosed by the health care provider when a grand mal seizure occurs in a child with a fever and no prior history of seizure disorders ( epilepsy ). In infants and young children, it is important to rule out other causes for a first-time seizure, especially meningitis.

In a typical febrile seizure, the examination usually shows no abnormalities other than the illness causing the fever. Typically, a full seizure workup including an EEG , head CT, and lumbar puncture ( spinal tap ) is not warranted.

However, the child's condition must meet strict medical criteria if these tests are to be avoided:

  • The child must be developmentally normal
  • The seizure must be generalized (not focal), meaning more than one part of the body is involved.
  • The seizure may not last longer than 15 minutes.
  • The child cannot have had more than one febrile seizure in 24 hours.
  • The child's neurologic exam performed by a physician must be normal to be called a simple febrile seizure.

If all of these criteria are met, no further studies are likely to be required.


During the seizure, leave your child on the floor. You may want to slide a blanket under him if the floor is hard. Move him only if he is in a dangerous location. Remove objects that may injure him. Loosen any tight clothing, especially around the neck. If possible, open or remove clothes from the waist up. If he vomits, or if saliva and mucus build up in the mouth, turn him on his side or stomach. This is also important if it looks like the tongue is getting in the way of breathing.

Expectations (prognosis)

Most children outgrow febrile seizures by age 5.

A small number of children who have had a febrile seizure go on to develop epilepsy, but not because of the febrile seizures. Children who would develop epilepsy anyway will sometimes have their first seizures during fevers. These are usually prolonged, complex seizures. Previous neurologic problems and a family history of epilepsy also make future epilepsy more common. The number of febrile seizures has no correlation with future epilepsy.


  • An injury from falling down or bumping into objects
  • Biting oneself
  • Breathing fluid into the lungs, pneumonia
  • Injury from prolonged or complicated seizures
  • Side effects of medications used to treat and prevent seizures (if prescribed)
  • Complications if a serious infection, such as meningitis, caused the fever
  • Seizures unrelated to fever

Calling your health care provider

  • Children should see a doctor as soon as possible after their first febrile seizure.
  • If the seizure is lasting several minutes, call 911 to have an ambulance bring your child to the hospital.
  • If the seizure ends quickly, drive the child to an emergency room when it is over.
  • A child should also see a doctor if repeated seizures occur during the same illness, or if this looks like a new type of seizure for your child.
  • Call or go in if any other symptoms occur before or after the seizure, such as nausea , vomiting , rash , tremors , abnormal movements, problems with coordination, drowsiness , restlessness , confusion , or sedation. It is normal for children to sleep or be briefly drowsy or confused immediately following a seizure.


To prevent future febrile seizures, give acetaminophen or ibuprofen at the first sign of a fever. (You may want to keep acetaminophen suppositories on hand). Then sponge your child with lukewarm water. Give him cool liquids to drink -- both to lower the temperature and keep him well hydrated

Update Date: 10/30/2003

Alan Greene, M.D., F.A.A.P., Department of Pediatrics, Stanford School of Medicine; Lucile Packard Children's Hospital; Chief Medical Officer, A.D.A.M., Inc.

©2009 [Privacy Policy] [Disclaimer]
Last updated: Tue, 06 Jan 2009 00:20:03 GMT