What are febrile seizures?
Febrile seizures most commonly happen in a child between six months and five years old. Though it looks scary, febrile seizures are common and generally not a cause for major concern.
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What are febrile seizures?
Febrile seizures most commonly happen in a child between six months and five years old. Though it looks scary, febrile seizures are common and generally not a cause for major concern.
A febrile seizure can happen in a child between the ages six months to five years old when they have a fever. A true fever is a temperature of 100.4 degrees Fahrenheit (38 degrees Celcius) or higher. Viral illnesses, like the flu or RSV, some vaccines, and genetic predisposition to seizures are common risk factors.
You may have recently heard the news that the FDA asked for a warning to be added to the flu shots, indicating that they may increase the risk of febrile seizures. It’s important to understand that the risk is higher with flu infections themselves, and what exactly febrile seizures are.
How are febrile seizures different from a seizure disorder?
Febrile seizures are specifically associated with a fever, whereas seizures that are part of a larger seizure disorder, aren’t caused by a fever. Seizures can also occur due to infections of the central nervous system (CNS). Importantly, febrile seizures do not involve a CNS infection. The central nervous system includes your brain and spinal cord.
How do you treat a simple febrile seizure?
As scary as they can be, febrile seizures aren’t normally a cause for major concern. They are usually not associated with negative effects on a kiddo’s future intellect or behavior. There are two types of febrile seizures, simple and complex: A simple febrile seizure lasts fewer than fifteen minutes, and it can cause a loss of consciousness. Simple seizures only occur once within a 24 hour period. A complex febrile seizure can last for longer than 15 minutes and are confined to one side of the body. More than one complex seizure can happen within 24 hours.
If the febrile seizure lasts for more than five minutes, a clinician will give a benzodiazepine to help with the seizure, but otherwise, simple febrile seizures aren’t treated outside of bringing the fever down. Though reducing the fever won’t stop or prevent a febrile seizure, it is still part of the treatment process. There isn’t any need to go through testing for simple febrile seizures, such as an electroencephalography (aka EEG, a test that measures brain activity) or do a lumbar puncture, also called a spinal tap. Rarely, a physician might do a lumbar puncture in a child who had a febrile seizure if they are concerned for meningitis, which is an infection of the layers of tissue around the brain. A seizure alone doesn’t necessarily suggest meningitis. But if the seizure occurs alongside neck stiffness, a specific rash (called a petechial rash), if they can’t be calmed or if they’re extremely drowsy, or if they have not been vaccinated for bacteria that commonly causes meningitis, then a clinician would be more concerned for meningitis. If the clinician is concerned about meningitis, they will give your child antibiotics.
For complex febrile seizures, your child might be admitted to the hospital if the seizure lasts more than thirty minutes or occur multiple times. They also might be given an anticonvulsant medication to help treat the seizure and they might be checked for a central nervous system infection called viral encephalitis.
Is there an increased risk of epilepsy if my child has a febrile seizure?
Yes, there is a very small increased risk of epilepsy if your child has a febrile seizure. Febrile seizures themselves do not cause epilepsy. Family history of febrile seizures are a very strong risk factor for a child having a febrile seizure. If a child has a febrile seizure, they are 32% more likely to have another febrile seizure versus a child who didn’t have a febrile seizure in the first place. There is around a 2% risk of epilepsy after a simple febrile seizure. If a child has a complex febrile seizure,then the risk of future epilepsy is around 6-8%. Though these statistics can sound very scary, according to pediatric neurologists, the relative risk is low and not something to worry that much about.
Can you prevent febrile seizures?
Unfortunately, nothing can really prevent febrile seizures. A 2021 meta-analysis showed that using fever-reducing medicines like tylenol and ibuprofen don’t prevent febrile seizures.
What about the recent FDA warning about febrile seizures and flu vaccines?
The FDA recently told pharmaceutical companies to include a warning about the risk of febrile seizures in children ages 6 months to 4 years with flu vaccines. A 2025 study showed that there is a small risk of febrile seizures with the flu vaccine. So should a small risk of febrile seizures make you hesitant about the flu vaccine? Not necessarily. According to the research, the risk of febrile seizure with flu is very low and even if a febrile seizure occurs, though it can seem scary, it’s generally nothing to worry about. And flu itself can cause febrile seizures. In the American Academy of Pediatrics report about flu vaccination, they cite research that shows that 8% to 11% of children hospitalized with influenza experience neurologic complications. It’s important to remember that viral infections are not necessarily a benign event and vaccines are a safe and effective way to prevent the flu.
If you’re worried about your kiddo getting a flu vaccine, it’s important to talk to your pediatrician about your child’s risk. The American Academy of Pediatrics continues to recommend the flu vaccine for children.
Overall, febrile seizures are an extremely scary experience for parents, but they almost always resolve on their own. If you’re worried, it’s always best to get it checked out by a pediatric clinician!
Resources:
American Family Physician: Febrile Seizures: Risks, Evaluation, and Prognosis
American Academy of Pediatrics: Febrile Seizures
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Back when I was about 6 yrs old, during an outbreak of I think what was the flu, I had such high fever I was experiencing horrific delirium during the day & worse of all at night where my sleep was so disrupted I was screaming/mumbling out loud. During the day I remember passing out into what looked like a seizure. My mom grabbed hold of me right before I passed out & thank god I didn't hit the floor. My body went limp in her arms/totally passed out... Even though I slowly recovered from this monster "flu" illness, the delirium continued on (but only after I fell into sleep at night). I was so terrified of the "left over delirium" episodes at night that I tried to stay awake/not go to sleep. It took couple weeks before the "left-over delirium" during sleep slowly went away. But I'm still terrified of the seizure/delirium experience. The best way I could describe the delirium was that it was similar to what people describe as the worst, most horrifying LSD trip ever... So please let this be a warning to parents of young children - do what is in your child's best interests to stay healthy!!!