Febrile Seizures

What Is It?

The brain's nerve cells (neurons) communicate with each other by giving off tiny electric signals. When someone has a seizure (convulsion), the way the brain's nerve cells give off signals suddenly changes, causing different muscles in the body to twitch or jerk uncontrollably. A seizure may affect only a small area of the brain and body (focal seizure), or it may involve the whole brain and body (generalized seizure).

Febrile seizures occur in children, and are caused by fever of at least 102 degrees Fahrenheit or by a sudden rise in body temperature. These febrile seizures usually happen at the beginning of an illness, soon after the fever appears. They affect about 3 percent of children and are most common between the ages of 6 months and 5 years.

Children are more likely to have a febrile seizure if:

• They have had febrile seizures before
• Other family members (brothers, sisters, parents) have had febrile seizures
• They have delays in normal development

About one in three children who have had a febrile seizure will have another one within one year, but most children eventually grow out of this condition. The risk of having another seizure is greater in children with a family history of febrile seizures and in children who had their first seizure when they were younger than 12 months old.

Symptoms

Signs of a febrile seizure may include:

• Jerky, twitching movements of the arms and legs
• Stiffness
• Rolling eyes
• Loss of consciousness (passing out)
• Not responding to voices or touch

Diagnosis

In most cases, a doctor can diagnose febrile seizures based on a description of the episode. However, the doctor may want to see your child to look for the cause of the fever. In particular, the doctor will want to make sure your child does not have any signs of a serious infection of the brain (encephalitis) or of the membranes that cover the brain and spinal cord (meningitis).

Expected Duration

Febrile seizures usually last only a few minutes. If they last longer than this, call your doctor right away.

Prevention

There is nothing that can be done to prevent first-time febrile seizures. In children who already have had one febrile seizure, some medications may help to prevent more seizures. However, the potential side effects of these drugs for your child may be worse than the benefits. The American Academy of Pediatrics does not recommend the use of these medications except in special circumstances. Instead, it recommends that parents of children at risk of febrile seizures be taught how best to manage a fever and what to do if a child has a seizure.