Most febrile seizures cannot be reliably prevented, and that’s one of the most frustrating truths for parents who’ve watched their child have one. Fever-reducing medications like acetaminophen and ibuprofen, which seem like the obvious solution, do not reduce the risk of a febrile seizure occurring. There are, however, specific strategies that can lower the chance of recurrence, and understanding the actual risk helps put things in perspective.
Why Fever Reducers Don’t Prevent Seizures
This is the single most important thing to know: giving your child fever-reducing medicine does not prevent febrile seizures. A randomized controlled trial published in JAMA Pediatrics found that children who received antipyretic medications had a recurrence rate of 23.4%, virtually identical to the 23.5% rate in children who received a placebo. The difference was statistically zero.
The reason is that febrile seizures appear to be triggered by how rapidly a fever rises, not by how high the temperature gets. By the time you notice your child has a fever and give them medicine, the rapid spike has already happened. Fever reducers still help your child feel more comfortable, and there’s no reason to stop using them for that purpose. They just won’t stop a seizure.
What Actually Lowers Recurrence Risk
About 25% to 30% of children who have a febrile seizure will have another one. That number climbs to nearly 50% for children who had their first seizure before age one. Younger age at first seizure, a family history of febrile seizures or epilepsy, and having had a complex febrile seizure (one lasting longer than 15 minutes, occurring more than once in 24 hours, or affecting only one side of the body) all increase the odds of recurrence.
For most children with simple febrile seizures, the American Academy of Pediatrics recommends against both daily and intermittent anti-seizure medication. The reasoning is straightforward: simple febrile seizures, while terrifying to watch, are generally harmless. The side effects of preventive medications outweigh the small risks posed by the seizures themselves.
When Medication Is Considered
In specific cases, particularly when parental anxiety is severe or a child has multiple risk factors for recurrence, doctors may prescribe oral diazepam to be given at the onset of a febrile illness (not during the seizure, but when the fever first appears). Studies show this approach can reduce recurrence, but it comes with trade-offs. In one study, about 37% of children experienced side effects like drowsiness and irritability.
Daily anti-seizure medications like phenobarbital do reduce febrile seizure recurrence, but a landmark study in the New England Journal of Medicine found that phenobarbital depresses cognitive performance in children, and this effect can persist for months after the drug is stopped. The cognitive cost simply isn’t worth it for a condition that is, in the vast majority of cases, benign. Valproic acid carries similar concerns, including rare but serious liver toxicity in young children.
Keeping Your Child Comfortable During Fevers
While comfort measures won’t prevent a seizure, they’re still the right thing to do when your child is sick. Dress your child in light clothing and use light bedding. Offer cool drinks frequently to keep them hydrated. You can dab them with a damp cloth, use a fan, or open a window, but stop if your child seems cold or uncomfortable. Avoid bundling a feverish child in heavy blankets, which can trap heat and make them feel worse.
The goal is comfort, not aggressively driving down the temperature number on the thermometer. A child who has a fever of 102°F but is drinking fluids and resting comfortably doesn’t need more intervention than one who is miserable at 100.5°F.
Vaccines and Febrile Seizure Risk
Certain vaccines carry a small, well-documented increase in febrile seizure risk, simply because they can cause a brief fever. The MMR vaccine is the most studied: there’s a slightly elevated risk during days 5 through 12 after the first dose. The combination MMRV vaccine (which adds chickenpox) carries a slightly higher risk than MMR given separately, which is one reason many pediatricians give the two components as separate shots for the first dose.
The flu shot can also slightly raise febrile seizure risk, but only when given on the same day as certain other vaccines (the pneumococcal vaccine or DTaP) in children between 6 months and 2 years. When the flu shot is given on a different day, this elevated risk disappears. If your child has a history of febrile seizures, ask your pediatrician about spacing vaccines out rather than giving multiple shots at one visit. This doesn’t mean skipping vaccines. The seizure risk from the actual diseases these vaccines prevent is far greater.
The Role of Family History and Genetics
Febrile seizures run strongly in families. If a parent or sibling had febrile seizures, your child’s risk is significantly higher. Studies of twins underscore this: among identical twins, when one twin had a febrile seizure, the other was far more likely to have one too compared to fraternal twins. Researchers have identified specific genetic mutations linked to recurrent febrile seizures, particularly in families where members also have certain epilepsy syndromes.
You can’t change your child’s genetics, but knowing the family history helps you and your pediatrician plan ahead. Parents with a strong family history can discuss whether intermittent diazepam makes sense for their child, and they can prepare themselves emotionally and practically for the possibility of a seizure during illnesses.
What Febrile Seizures Mean Long-Term
Children who have febrile seizures do have a higher rate of developing epilepsy later in life compared to children who never had one. However, the absolute risk remains low. The vast majority of children who have febrile seizures never develop epilepsy. The risk is higher in children who had complex febrile seizures, had a family history of epilepsy, or had neurological concerns before the seizure.
For children with simple febrile seizures and no other risk factors, the AAP does not recommend EEGs, blood work, or brain imaging. These tests don’t change management and don’t predict who will or won’t have another seizure.
What to Do During a Febrile Seizure
Since prevention is limited, preparation matters. Place your child on their side on a flat surface. Do not put anything in their mouth. Note the time the seizure starts. Most febrile seizures stop on their own within one to two minutes. Medical guidelines recommend that treatment begin if a seizure lasts longer than five minutes, so call emergency services if it reaches that point. A seizure lasting 30 minutes or more is classified as a neurological emergency, though this is rare.
After a short seizure, your child may be sleepy or confused for a little while. This is normal. If it was your child’s first febrile seizure, have them evaluated by a doctor afterward to confirm the diagnosis and rule out other causes of the seizure, such as an infection of the brain or spinal cord.