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Seizures and Fever (cont.)


Parents commonly ask 3 questions about febrile seizures.

Are they harmful to my child?

  • Parents should feel reassured that febrile seizures, except in the very rare cases in which they are extremely prolonged and last 20-30 minutes, do not result in any lasting ill effects such as brain damage, decreased intelligence, behavioral problems, or delay in development.
  • Although otherwise healthy children who have had a simple febrile seizure may have a slightly higher risk of epilepsy later in life, there is no evidence that the febrile seizure itself causes epilepsy. There is a somewhat higher incidence of later epilepsy if certain risk factors are present: complex febrile seizure, family history of nonfebrile seizures, or preexisting neurologic abnormality or prior delay in development. Placing a child on continued antiseizure (anticonvulsant) medication after a febrile seizure does not prevent later epilepsy.

What are the chances they will reoccur?

  • In general, 30-40% of children who have had a febrile seizure will experience more. If a child has had 2 febrile seizures, there is a 50% chance of an additional episode.
  • Factors that increase this risk are children younger than 12 months at the time of the first episode and fever higher than 102°F at the time of the first episode.

Should my child be put on medication to prevent more seizures?

  • Even without anticonvulsant medication, most children will never have a recurrence. Febrile seizures themselves cause no lasting ill effects such as brain damage or epilepsy. Certain anticonvulsant medications, such as phenobarbital, valproic acid, and diazepam, can lower the recurrence rate to about 10%. Each of these medications has drawbacks:
    • Phenobarbital was once widely used to prevent recurrences. However, it must be given on a daily basis to maintain adequate blood levels. Although febrile seizures themselves have no effect on behavior or learning, phenobarbital does.
    • Valproic acid (brand names Depakene and Depakote) must also be given daily. Although side effects are rare, some, such as liver damage, have been fatal.
    • Rectal diazepam (brand name Diastat—it is the same medicine in Valium) has the advantage in that it only needs to be used when the child has fever. However, it is not unusual that a child may have a febrile seizure before the parent is even aware there is a fever. Also, because diazepam is a sedative, the drowsiness it causes may make an already sick child appear more ill, creating difficulty in determining whether the child has a serious infection.
    • Doctors have concluded that the drawbacks of anticonvulsant treatment generally outweigh the benefits and do not routinely prescribe these medications. A physician may prescribe such medication for children with special circumstances, such as developmental problems or very strong family history of such seizures. Children outgrow febrile seizures by age 5-6 years.

Medically reviewed by Joseph Carcione, DO; American board of Psychiatry and Neurology


"Clinical features and evaluation of febrile seizures"

Medically Reviewed by a Doctor on 9/9/2015
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