A febrile seizure typically looks like sudden, uncontrolled shaking of the entire body, with the child losing consciousness and becoming unresponsive. The episode usually lasts less than a few minutes and is triggered by a fever, most commonly in children between 6 months and 5 years old. It is terrifying to watch, but febrile seizures affect 2% to 5% of young children and are, in the vast majority of cases, harmless.
What You’ll See During a Febrile Seizure
The most common presentation is a child who suddenly goes stiff, loses consciousness, and begins jerking or shaking their arms and legs rhythmically. Their eyes may roll back or fix in one direction. Their skin might look flushed from the fever or temporarily appear pale or slightly blue, especially around the lips, because breathing becomes irregular during the shaking.
Some febrile seizures look different. Instead of full-body shaking, a child may simply go rigid and stiff without much visible movement, or twitch in just one part of their body. The child will not respond to you during the episode, no matter what you say or do. They may also lose bladder or bowel control. The whole thing can start without warning: a child who seemed fine moments ago (or who you didn’t even realize had a fever yet) can suddenly collapse and begin convulsing.
How Long It Lasts
Most febrile seizures last less than a few minutes, and the vast majority are under 15 minutes. A seizure under 15 minutes that involves the whole body and happens only once in a 24-hour period is classified as a “simple” febrile seizure. This is the most common type.
A “complex” febrile seizure is one that lasts 15 minutes or longer, involves movement on only one side of the body, or happens more than once within 24 hours. Complex febrile seizures require closer medical evaluation, but they are still not the same as epilepsy.
What Happens Right After
Once the shaking stops, your child won’t just bounce back to normal. The period immediately following a seizure brings its own set of symptoms. Children are commonly drowsy, confused, and exhausted. They may not recognize you right away or may seem dazed for several minutes to an hour. Some children are irritable or cry, while others fall into a deep sleep. Muscle soreness and general weakness are also normal in the aftermath.
This recovery period can be almost as alarming as the seizure itself, but the grogginess and confusion are expected. Most children return fully to themselves within an hour or so.
What Triggers Them
Febrile seizures are triggered by fever, but not necessarily a very high one. They occur in children between 6 and 60 months of age. The speed at which a child’s temperature rises may matter as much as the peak temperature itself, which is why a febrile seizure sometimes happens before a parent even realizes the child is sick. Common childhood illnesses like ear infections, respiratory viruses, and roseola are typical triggers.
There is a genetic component. Children with a family history of febrile seizures are at higher risk, and younger children (under 18 months) are more likely to experience them and to have recurrences.
Risk of It Happening Again
After a first febrile seizure, recurrence risk over the next two years ranges from about 15% to 70%, depending on how many risk factors a child has. With no risk factors, the two-year recurrence rate is around 14%. With one risk factor, it climbs above 20%. Children with three or four risk factors (young age, lower fever at the time, short duration of fever before the seizure, and family history) face recurrence rates above 60%.
Despite how frightening they are, simple febrile seizures do not cause brain damage, do not lead to developmental problems, and carry only a very slightly elevated risk of epilepsy compared to the general population.
When It’s an Emergency
If this is your child’s first febrile seizure, seek medical attention right away so a doctor can evaluate them. For any febrile seizure that lasts longer than five minutes, call an ambulance. Also call for emergency help if the seizure stops but the child doesn’t seem to recover quickly, or if they show signs of a more serious infection: a stiff neck, extreme sleepiness beyond normal post-seizure drowsiness, difficulty breathing, or repeated vomiting.
What to Do While It’s Happening
Place the child on a soft surface on their side to keep the airway clear. Do not put anything in their mouth, do not try to hold them down, and do not attempt to restrain the jerking. Move nearby objects out of the way so they can’t injure themselves. Note the time the seizure started so you can tell medical providers how long it lasted. Once it ends, keep them on their side while they recover and stay with them until they’re fully alert.