Febrile seizures

[Dorothey Allen]

Febrile seizures are seizures triggered by a fever of at least 100.4° F (about 38° C).

Most febrile seizures are harmless and caused by fever from a minor infection.
Less often, a febrile seizure is the first sign of a previously unrecognized neurologic disorder.
Doctors sometimes do blood tests and a spinal tap to check for serious disorders that can cause seizures.
Children generally need drugs to end the seizure only if it lasts 5 minutes or more to minimize the risk of a long-lasting seizure or status epilepticus.
Most children do not need to take drugs to prevent seizures.

A seizure is an abnormal, unregulated electrical discharge of nerve cells in the brain or part of the brain. This abnormal electrical discharge can cause

Convulsions
Involuntary movements
Altered awareness
Abnormal sensations

Convulsions are violent, involuntary, jerking and stiffening of muscles in a large part of the body.
Febrile seizures occur in about 2 to 5% of children 6 months to 5 years of age but most often occur in children between 12 months and 18 months of age. A seizure that occurs in a child who has a fever and is 6 years old or older is not considered a febrile seizure. (See also Seizures in Children.)
Febrile seizures may run in families.
Most febrile seizures last much less than 15 minutes, and about two thirds of children who have a febrile seizure never have another one.
Febrile seizures may be simple or complex:

Simple: The entire body shakes (called a generalized seizure) for less than 15 minutes and children usually lose consciousness. Over 90% of febrile seizures are simple. This type of febrile seizure does not occur more than once in a 24-hour period.
Complex: The entire body shakes for 15 minutes or more (constantly or with pauses), or only one side or one part of the body shakes (called a partial or focal seizure), or seizures occur at least twice within 24 hours. Children who have complex febrile seizures are slightly more likely to develop a seizure disorder later during childhood.

After the febrile seizure, children often appear confused or not themselves for a few minutes. The period of confusion (postictal period) sometimes lasts up to a few hours.
Febrile seizures usually result from the fever itself. Most often, the fever is caused by an otherwise minor infection such as a viral respiratory infection or an ear infection. In such cases, the infection and the seizure are harmless. An important part of the definition of febrile seizures is that the fever and seizure are not caused by a brain infection such as meningitis or encephalitis.