Febrile seizures are seizures that happen in children because of a fever. These seizures are usually short-lived and harmless. The overwhelming majority of children who have them will recover quickly and won’t experience any long-term effects or complications. But between 2.5% and 5% of children who have complex febrile seizures will develop epilepsy.
A fever causes a febrile seizure in your child. These types of seizures are age-specific, happening in infants as young as 6 months and children up to 5 years old. Febrile seizures most commonly occur between 12 and 18 months of age. They’re usually harmless, and most don’t have a lasting effect.
Simple febrile seizures are those that have all three of the following:
If any of the three above criteria aren’t true, it’s a complex febrile seizure. Complex febrile seizures are more likely to require treatment and may suggest an increased risk of seizure disorders later in life.
Hallmark symptoms of a febrile seizure include:
Fever causes febrile seizures. Febrile seizures are most common during the first day of an illness as a child's temperature rises. They're most likely with a fever of at least 100.4 degrees Fahrenheit (38 degrees Celsius). In some cases, children will sometimes have a seizure before developing a fever.
Fevers from viral infections usually trigger febrile seizures. But the fevers may be due to any type of infection, including:
(Note: Some childhood vaccinations may cause fever, and if a child has a febrile seizure after vaccination, it is the fever, not the vaccine itself, that causes the seizure.)
Children who have one febrile seizure have a higher chance of having another later on. The risk of a child having a second febrile seizure is about 1 in 3. About 10% of children who have one febrile seizure will have three or more throughout their entire childhood. The risk is highest in children who have a febrile seizure before turning 1 year old.
Simple febrile seizures usually don’t need treatment. They rarely last more than a few minutes, and children recover quickly from them. Parents can give fever-reducing medications during febrile illnesses, such as acetaminophen (Tylenol) or ibuprofen (Motrin), but these may not prevent febrile seizures from happening.
Complex febrile seizures are more likely to need treatment. For children who tend to have prolonged febrile seizures, rectal diazepam (Diastat) may be prescribed for home use. This is typically used in case of a seizure that last longer than five minutes or if the child has more than one seizure in 24 hours.
Rarely, daily prescription antiseizure medications are used to prevent febrile seizures. In most cases, this is not necessary.
You shouldn’t try to treat a first-time febrile seizure at home. A first-time febrile seizure needs immediate medical care to make sure that it isn’t another kind of seizure or that it isn’t happening because of a severe infection like meningitis or encephalitis (both of which can be life-threatening).
If your child has a history of febrile seizures, your healthcare provider can guide you on what to do to treat these at home. In general, you should do the following:
Febrile seizures happen unpredictably and are usually not preventable.
All first-time febrile seizures need emergency medical care in a hospital emergency room or another kind of emergency setting.
If your child has a history of febrile seizures, your child’s pediatrician can offer the best guidance on what you can and should do to treat these seizures. They can also tell you any signs that your child needs medical care.
In general, you should call your child’s pediatrician in the following cases:
You should get emergency medical care for febrile seizures in any of the following situations:
Simple febrile seizures are typically harmless. Researchers have found no evidence of long-term harm from simple febrile seizures. There’s also little to no evidence that simple febrile seizures increase the risk of developing epilepsy.
Complex febrile seizures are associated with a slightly increased chance of future seizure disorders. According to the available research, between 2.5% and 5% of children with complex febrile seizures will develop epilepsy. However, most children who have complex febrile seizures don’t have any long-term effects.
A note from Cleveland Clinic
Febrile seizures can be frightening, especially if your child has never had one before. However, most febrile seizures are short-lived, and children quickly recover from them without any long-term effects. If you have questions or concerns, you should talk to your child’s pediatrician. They can offer guidance and information that can help you understand the risks. They can also help set your mind at ease and show you how to do seizure first aid, so you can feel prepared if your child has a febrile seizure in the future.
Last reviewed by a Cleveland Clinic medical professional on 04/23/2022.
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