What are febrile seizures?
Febrile seizures are seizures or convulsions that occur in young children. They are triggered by fever typically above 101 degrees Fahrenheit (38.3 degrees Celsius). Seizures may happen during illnesses such as a cold, the flu, or an ear infection. In some cases, a child may not have a fever at the time of the seizure but will develop one a few hours later.
Having a febrile seizure does not mean a child has epilepsy. Epilepsy involves repeat seizures that are not triggered by fever.
Symptoms may include:
- Loss of consciousness or passing out
- Uncontrollable shaking
- Eye rolling
- Rigid (stiff) limbs
Less commonly, a child can become rigid or have twitches in only part of the body.
Most febrile seizures last a minute or two. Yet some may only last a few seconds and others may last for more than 15 minutes.
Febrile seizures that last less than 15 minutes do not cause any long-term health problems. However, if another one happens, it is more likely to be prolonged or longer than 15 minutes. A first febrile seizure that is prolonged does not boost the risk of having more. Even prolonged seizures are generally harmless on their own, but they do carry an increased risk of developing epilepsy.
Who is more likely to get febrile seizures?
About one in every 25 children will have at least one febrile seizure. Young children between the ages of about 6 months and 5 years old are the most likely to have febrile seizures. Children are at the greatest risk of having a febrile seizure at age 2. The older a child is when the first febrile seizure occurs, the less likely that child is to have more as there will be less time spent in the age group at risk.
About 40 percent of children who have one febrile seizure will have another. Certain things increase the risk for more febrile seizures, including:
- Young age—Children who have their first febrile seizure when they are younger than 18 months are at an increased risk of having another one.
- Family history—Children whose family members had febrile seizures are more likely to have more than one seizure.
- First sign of illness—Children who have febrile seizures before exhibiting other symptoms of an illness are at greater risk of having multiple seizures.
- Low temperature—Children are more likely to have another febrile seizure if the first one was accompanied by a relatively low temperature.
How are febrile seizures diagnosed and treated?
Diagnosing febrile seizures
To diagnose febrile seizures in infants and children, healthcare providers will review a child's medical history and perform a physical exam. They often test blood and urine to help pinpoint the cause of the fever. Keep in mind that dehydration from severe diarrhea or vomiting can cause seizures.
Meningitis, an infection of the membranes surrounding the brain, can cause both fever and seizures that can look like febrile seizures but are much more serious. If meningitis is suspected, health care providers may remove and test a small amount of the fluid that surrounds the brain and spinal cord.
Most of the time, children who have febrile seizures will not need to be in the hospital. Healthcare providers may recommend hospitalization if:
- The seizure is prolonged
- The child has a serious infection
- The child is younger than 6 months of age
Treating febrile seizures
Parents and caregivers should remain calm, take first aid measures, and carefully watch the child. During a febrile seizure, parents and caregivers should:
- Note the start time of the seizure. If it lasts longer than five minutes, call an ambulance. The child should be taken right away to the nearest medical facility.
- Call an ambulance if the seizure is less than five minutes but the child does not seem to be recovering quickly.
- Gradually place the child on a protected surface such as the floor to prevent injury. Do not restrain or hold a child during a convulsion.
- Put the child on his or her side or stomach to prevent choking. When possible, gently remove any objects from the child's mouth. Nothing should ever be placed in the child's mouth during a seizure. These objects can block airway and make it hard to breathe.
- Seek immediate medical attention if this is the child's first febrile seizure. Once it is over, take the child to the doctor to check for the cause of the fever. This is especially urgent if the child shows these symptoms of meningitis, an infection over the brain surface, which can include stiff neck, extreme lethargy, or a lot of vomiting.
Drugs that lower fevers such as acetaminophen or ibuprofen may provide comfort yet studies show that treating a fever does not lower the risk of febrile seizure. Healthcare providers may recommend other medications to control seizures if needed.
How can I or my loved one help improve care for people with febrile seizures?
Consider participating in a clinical trial so clinicians and scientists can learn more about febrile seizures and related disorders. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.
All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.
For information about participating in clinical research visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with febrile seizures at Clinicaltrials.gov.
Where can I find more information about febrile seizures?
Information may be available from the following resources:
Centers for Disease Control and Prevention (CDC)
Citizens United for Research in Epilepsy (CURE)
Phone: 312-225-1801 or 844-231-2873
Phone: 301-459-3700 or 800-332-1000