Index:                

   * What are febrile seizures?
   * How common are febrile seizures?
   * What makes a child prone to recurrent febrile seizures?
   * Are febrile seizures harmful?
   * What should be done for a child having a febrile seizure?
   * How are febrile seizures diagnosed and treated?
   * How are febrile seizures prevented?
   * What research is being done on febrile seizures?
   * Where can I get more information?                

---------------------------------------------------------------------------                

Febrile seizures are convulsions brought on by a fever in infants or small
children. During a febrile seizure, a child often loses consciousness and
shakes, moving limbs on both sides of the body. Less commonly, the child
becomes rigid or has twitches in only a portion of the body, such as an arm
or a leg, or on the right or the left side only. Most febrile seizures last
a minute or two, although some can be as brief as a few seconds while
others last for more than 15 minutes.                

The majority of children with febrile seizures have rectal temperatures
greater than 102 degrees F. Most febrile seizures occur during the first
day of a child's fever.                

Children prone to febrile seizures are not considered to have epilepsy,
since epilepsy is characterized by recurrent seizures that are not
triggered by fever.                

How common are febrile seizures?                

Approximately one in every 25 children will have at least one febrile
seizure, and more than one-third of these children will have additional
febrile seizures before they outgrow the tendency to have them. Febrile
seizures usually occur in children between the ages of 6 months and 5 years
and are particularly common in toddlers. Children rarely develop their
first febrile seizure before the age of 6 months or after 3 years of age.
The older a child is when the first febrile seizure occurs, the less likely
that child is to have more.                

What makes a child prone to recurrent febrile seizures?                

A few factors appear to boost a child's risk of having recurrent febrile
seizures, including young age (less than 15 months) during the first
seizure, frequent fevers, and having immediate family members with a
history of febrile seizures. If the seizure occurs soon after a fever has
begun or when the temperature is relatively low, the risk of recurrence is
higher. A long initial febrile seizure does not substantially boost the
risk of recurrent febrile seizures, either brief or long.                

Are febrile seizures harmful?                

Although they can be frightening to parents, the vast majority of febrile
seizures are harmless. During a seizure, there is a small chance that the
child may be injured by falling or may choke from food or saliva in the
mouth. Using proper first aid for seizures can help avoid these hazards
(see section entitled "What should be done for a child having a febrile
seizure?").                

There is no evidence that febrile seizures cause brain damage. Large
studies have found that children with febrile seizures have normal school
achievement and perform as well on intellectual tests as their siblings who
don't have seizures. Even in the rare instances of very prolonged seizures
(more than 1 hour), most children recover completely.                

Between 95 and 98 percent of children who have experienced febrile seizures
do not go on to develop epilepsy. However, although the absolute risk
remains very small, certain children who have febrile seizures face an
increased risk of developing epilepsy. These children include those who
have febrile seizures that are lengthy, that affect only part of the body,
or that recur within 24 hours, and children with cerebral palsy, delayed
development, or other neurological abnormalities. Among children who don't
have any of these risk factors, only one in 100 develops epilepsy after a
febrile seizure.                

What should be done for a child having a febrile seizure?                

Parents should stay calm and carefully observe the child. To prevent
accidental injury, the child should be placed on a protected surface such
as the floor or ground. The child should not be held or restrained during a
convulsion. To prevent choking, the child should be placed on his or her
side or stomach. When possible, the parent should gently remove all objects
in the child's mouth. The parent should never place anything in the child's
mouth during a convulsion. Objects placed in the mouth can be broken and
obstruct the child's airway. If the seizure lasts longer than 10 minutes,
the child should be taken immediately to the nearest medical facility for
further treatment. Once the seizure has ended, the child should be taken to
his or her doctor to check for the source of the fever. This is especially
urgent if the child shows symptoms of stiff neck, extreme lethargy, or
abundant vomiting.                

How are febrile seizures diagnosed and treated?                

Before diagnosing febrile seizures in infants and children, doctors
sometimes perform tests to be sure that seizures are not caused by
something other than simply the fever itself. For example, if a doctor
suspects the child has meningitis (an infection of the membranes
surrounding the brain), a spinal tap may be needed to check for signs of
the infection in the cerebrospinal fluid (fluid that bathes the brain and
spinal cord). If there has been severe diarrhea or vomiting, dehydration
could be responsible for seizures. Also, doctors often perform other tests
such as examining the blood and urine to pinpoint the cause of the child's
fever.                

A child who has a febrile seizure usually doesn't need to be hospitalized.
If the seizure is prolonged or is accompanied by a serious infection, or if
the source of the infection cannot be determined, a doctor may recommend
that the child be hospitalized for observation.                

How are febrile seizures prevented?                

If a child has a fever most parents will use fever-lowering drugs such as
acetaminophen or ibuprofen to make the child more comfortable, although
there are no studies that prove that this will reduce the risk of a
seizure. One preventive measure would be to try to reduce the number of
febrile illnesses, although this is often not a practical possibility.                

Prolonged daily use of oral anticonvulsants, such as phenobarbital or
valproate, to prevent febrile seizures is usually not recommended because
of their potential for side effects and questionable effectiveness for
preventing such seizures.                

Children especially prone to febrile seizures may be treated with the drug
diazepam orally or rectally, whenever they have a fever. The majority of
children with febrile seizures do not need to be treated with medication,
but in some cases a doctor may decide that medicine given only while the
child has a fever may be the best alternative. This medication may lower
the risk of having another febrile seizure. It is usually well tolerated,
although it occasionally can cause drowsiness, a lack of coordination, or
hyperactivity. Children vary widely in their susceptibility to such side
effects.                

What research is being done on febrile seizures?                

The National Institute of Neurological Disorders and Stroke (NINDS), a part
of the National Institutes of Health (NIH), sponsors research on febrile
seizures in medical centers throughout the country. NINDS-supported
scientists are exploring what environmental and genetic risk factors make
children susceptible to febrile seizures. Some studies suggest that women
who smoke or drink alcohol during their pregnancies are more likely to have
children with febrile seizures, but more research needs to be done before
this link can be clearly established. Scientists are also working to
pinpoint factors that can help predict which children are likely to have
recurrent or long-lasting febrile seizures.                

Investigators continue to monitor the long-term impact that febrile
seizures might have on intelligence, behavior, school achievement, and the
development of epilepsy. For example, scientists conducting studies in
animals are assessing the effects of seizures and anticonvulsant drugs on
brain development.                

Investigators also continue to explore which drugs can effectively treat or
prevent febrile seizures and to check for side effects of these medicines.                

Where can I get more information?                

Additional information for patients, families, and physicians is available
from: Epilepsy Foundation of America 4351 Garden City Drive Landover,
Maryland 20785 (301) 459-3700 (800) EFA-1000 (332-1000)                

---------------------------------------------------------------------------                

For more information on research on febrile seizures, you may wish to
contact:
Office of Scientific and Health Reports
NIH Neurological Institute
P.O. Box 5801
Bethesda, Maryland 20824 (301) 496-5751                

---------------------------------------------------------------------------                

Prepared by
Office of Scientific and Health Reports
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, Maryland 20892-2540
NIH Publication No. 95-3930
September 1995                

Last Updated: October 28, 1997.             

Number of hits to this Febrile Seizure page: