What is a febrile seizure?

A febrile seizure, also known as a fever seizure, is a seizure caused by a fever. They can occur when your child has a fever of 38ºC (100.4ºF) or higher. During a febrile seizure, a child may have shaking or jerking movements of their body, head, arms or legs and may lose consciousness.

Febrile seizures usually last from 30 seconds to 2 minutes. However, they can be as short as a few seconds or last for more than 15 minutes.

How serious is a febrile seizure?

A febrile seizure is not harmful and usually stops by itself. If your child has had a febrile seizure, it does not mean that they will develop epilepsy.

Children at higher risk of developing epilepsy include those who have:

• A family history of epilepsy
• Cerebral palsy
• A history of delayed development
• A neurological condition
• A febrile seizure lasting 30 minutes or more
• A second seizure within 24 hours of the first

What can cause a febrile seizure?

Febrile seizures can happen with any condition that causes a fever. Conditions that can cause a fever include common childhood illnesses such as a cold, the flu, an ear infection, or roseola.

Rarely, children who develop a fever after immunization have a febrile seizure. This is not a reason to discontinue future immunizations.

Who is most likely to have a febrile seizure?

Febrile seizures occur in children between the ages of 6 months and 5 years. About 1 in 25 children will have a febrile seizure during childhood. A child is more likely to have a febrile seizure if a parent, brother or sister has had one. About 1 in 3 children who have a febrile seizure will have another one. The older the child is when they have a febrile seizure the less likely they are to have another.

Can febrile seizures be prevented?

Febrile seizures cannot usually be prevented. Fever can be reduced by medications such as acetaminophen and ibuprofen but this has not been shown to prevent febrile seizures. Oral medication must not be given to a child during a seizure to avoid the risk of choking.

What should I do if my child is having a febrile seizure?

If your child has a febrile seizure, the Canadian Paediatric Society recommends that you do the following:

• Stay as calm as you can
• Place your child on a flat surface on their side. This is to protect their airway in case they vomit (throw up)
• Do not move them unless they are in danger or near something dangerous
• Do not restrain them
• Wipe away any vomit or saliva outside the child’s mouth, but do not put anything between their teeth
• After the seizure stops, keep your child on their side
• Allow your child to sleep after the seizure and wake them up gradually
• Call 9-1-1 if the seizure lasts longer than 3 minutes or if the child is younger than 6 months

If your child has had a seizure, even a brief one, you should take them to their health care provider to determine the cause of the seizure.

For more information

For information on taking a temperature, see HealthLinkBC File #99 How to take a temperature: Children and adults.