Genetic epilepsy with febrile seizures plus (GEFS+)

Genetic epilepsy with febrile seizures plus (GEFS+) is an unusual epilepsy syndrome. It usually affects several members of the same family.

GEFS+ may cause a range of different seizures but febrile seizures are the most common.

Who gets genetic epilepsy with febrile seizures plus (GEFS+)?

GEFS+ is a genetic condition that runs in families. It can affect several members of a family. People with GEFS+ have a change (called a ‘mutation’) in a gene. A common gene affected is the SCN1A gene but others include SCN1B and GABRG2. There are likely to be many other genes that haven’t been identified yet. The altered genes are usually passed down from parent to child. Sometimes mutations happen for the first time without it affecting other family members.

A child with GEFS+ may have family members who had seizures. These could be febrile seizures, other seizure types, or different epilepsy syndromes . These may include Dravet syndrome and Epilepsy with myoclonic-atonic seizures (Doose syndrome).


GEFS+ can cause many different types of seizure. The full name for GEFS+ used to be ‘Generalised epilepsy with febrile seizures plus’. This was because it was thought people with the syndrome only had generalised seizures (seizures that affect both sides of the brain). It’s now well known that people with GEFS+ also get focal seizures (seizures that start in one area of the brain).

The seizure types in this syndrome vary from person to person. These are described below. The main seizure type in GEFS+ is febrile seizures.

  • Febrile seizures (febrile convulsions)

    Febrile seizures are seizures triggered by having a high temperature (fever). They’re often linked with having a virus or infection. The seizures are usually generalised tonic-clonic seizures. They tend to last a few minutes, but sometimes they can last longer.

    The usual age range for this type of seizure is 6 months to 5 years. Most children with febrile seizures will have them between 18 months and 3 years of age.

  • Febrile seizures plus

    This is the term used when children have febrile seizures beyond the normal age range. This can be before the age of 6 months, or older than 5 or years. Most children stop having seizures in their late childhood or early teenage years.

    Febrile seizures plus can lead to other types of seizures unrelated to fever. Children may have extra seizures alongside the febrile seizures.

  • Other seizure types

    GEFS+ can be associated with many other types of seizures. Some children may only have short seizures. Others may have longer and more severe ones. They may include:

    • Tonic-clonic seizures – stiffness and jerking movements with loss of consciousness
    • Absence seizures – where your child ‘switches off’ or loses awareness
    • Myoclonic seizures – where your child has sudden jerking movements
    • Atonic seizures – where your child goes floppy and falls to the ground
    • Focal seizures – these affect one area of the brain. They may cause changes in awareness, movements or sensations

A few children may develop Dravet syndrome or Epilepsy with myoclonic-atonic seizures (EMAtS). These are more severe epilepsy syndromes.

The majority of people with GEFS+ don’t have any learning or development difficulties.


A specialist doctor called a paediatrician should assess your child if they have had a febrile seizure. The specialist will ask questions about your child’s seizures. They will need to take a detailed family history. This may involve talking to family members, particularly grandparents. This is because they may remember family members having seizures as children.

Your child’s specialist may recommend some tests. This will depend on the type of seizures your child has. These may include an EEG (electroencephalogram). This is to look at electrical activity in your child’s brain. They may also have brain scans such as an MRI (magnetic resonance imaging).

The paediatrician may also refer your child to a specialist in children’s epilepsy. They will be a paediatric neurologist. This is likely if your child seems to be developing another syndrome. These could include Dravet syndrome or EMAtS (epilepsy with myoclonic-atonic seizures). This could also happen if your child’s seizures are happening often.

You may be given a diagnosis of GEFS+ as a family. This could happen if your child has febrile seizures and there’s a history of seizures in the family too. If a mutation in a gene is found in your child and other family members, this will confirm the diagnosis.

Your child and any other affected family members may be offered a genetic test to look for any gene mutations. This is usually a simple blood test. Identifying a particular mutation can help understand how your child’s epilepsy may progress. If there is a family history of epilepsy, you and your child will also have a referral to a specialist. This will be a clinical geneticist. These specialists diagnose and look after families with genetic disorders. This will be to discuss any genetic test results and help with planning future pregnancies.


Your child’s treatment will depend on the type of seizures they have. If your child has febrile seizures only, they won’t need regular treatment with epilepsy medicines. If your child has other seizure types, the paediatrician is likely to prescribe epilepsy medicines. The choice of medicine will depend on the seizure type or types that your child has. The most commonly used medicines are:

  • Sodium valproate
  • Levetiracetam
  • Lamotrigine
  • Clobazam
  • Topiramate

In some cases, your child may need a combination of epilepsy medicines to treat seizures. This is more likely if your child has a more severe form of epilepsy, such as EMAtS or Dravet syndrome.

Sodium valproate can harm an unborn baby if taken during pregnancy. For this reason, if your child is able to get pregnant, or may do when they’re older, your child’s paediatrician will usually suggest an alternative medicine. If they do recommend treatment with sodium valproate, they will discuss the risks and benefits with you and your child first.

If your child has this syndrome, they may have seizures that last a long time or happen one after another. This is called status epilepticus. Your child’s paediatrician will discuss a ‘rescue’ or emergency care plan with you. This is to treat any prolonged or repeated seizures. These are a medical emergency.

You can find information about treatments on the Medicines for Children website.

The St John’s Ambulance website has information on how to put a baby in the recovery position. You can’t prevent a febrile seizure so you shouldn’t sponge them with cold water or try to take their clothes off.


The outlook for your child depends on the type of seizures that they have. Febrile seizures usually stop after the age of 6 years, but children with GEFS+ can have them for longer. Most children will stop having seizures in late childhood or early teenage years. It is rare for seizures to continue into adult life.

Your child’s paediatric neurologist will be able to tell you whether it’s possible they may have EMAtS or Dravet syndrome. Sometimes this only becomes clear over a number of months or years.

Epilepsy Action has information and support for parents of children with epilepsy.


Contact – for families with disabled children

Freephone helpline: 0808 808 3555


Dravet Syndrome UK

Charity dedicated to improving the lives of people affected by Dravet Syndrome through support, education and medical research.
Phone: 01246 912 421

This information has been produced under the terms of the PIF TICK. The PIF TICK is the UK-wide Quality Mark for Health Information. Please contact if you would like a reference list for this information.
Published: October 2023
Last modified: April 2024
To be reviewed: October 2026
Tracking: A026.06 (previously S026)
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