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There is particular concern that prolonged febrile convulsions cause mesial temporal
sclerosis. The data provided by the CHES cohort led to the following conclusions:

 If prolonged febrile convulsions actually cause temporal lobe damage (rather than being
the first overt evidence of such damage) it happens relatively rarely (three children out of
392 with febrile convulsions in the cohort).

 If damage does occur it is likely to have happened by the time that the child first gets to a
doctor (most children with complex febrile convulsions have them as the first attack).

 Recommendations that have been made about the use of prophylactic anticonvulsants in
children with febrile convulsions have been unduly influenced by the anxiety about this
very small group of children.

Studies have cast doubt on the effectiveness of anticonvulsants in preventing recurrences of
febrile seizures. A British study of the use of sodium valproate and phenobarbitone in
preventing recurrence of febrile convulsions was analysed on an intention-to-treat basis. The
overall risk of recurrrence was 30% and prophylactic treatment did not lessen this risk79.
Newton80 pooled the results from six British trials of phenobarbitone and four of valproate
and analysed them on an intention-to-treat basis, showing little overall value in treating
children who have febrile convulsions with anticonvulsants. Farwell et al81 studied the use of
phenobarbitone in children who had had at least one febrile convulsion and were at
heightened risk of further convulsions. The results showed that phenobarbitone depressed
cognitive performance in children treated for febrile convulsions and that this may outlast the
administration of the drug by several months. There was no reduction in the rate of recurrence
of febrile convulsions in the phenobarbitone group compared to the placebo group.

A Cochrane Database systematic review by Offringa and Newton concluded that no clinically
important benefits for children with febrile seizures were found for intermittent oral
diazepam, phenytoin, phenobarbitone, intermittent rectal diazepam, valproate, pyridoxine,
intermittent phenobarbitone, or intermittent ibuprofen, nor for diclofenac versus placebo
followed by ibuprofen, acetaminophen or placebo. Adverse effects of drugs were reported in
up to 30% of children. They concluded that parents should be supported with practical advice
and reassured about the benign nature of recurrent febrile seizures82.

Summary

General outcome
Febrile convulsions are common. The majority are simple febrile convulsions  brief
generalised seizures that occur just once in the lifetime of normal children. The evidence is
that most children who have febrile convulsions of any type (simple or complex) are
subsequently normal in intellect, neurological function and behaviour.

Subsequent epilepsy
For most children with febrile convulsions the risk of later epilepsy is little different from
that in the general population. A minority of children who have febrile convulsions are at
increased risk of developing epilepsy  those that are neurologically or developmentally
abnormal before the convulsions and some of those who have febrile convulsions with
complex features, particularly if focal.

Initial management
Most febrile convulsions stop spontaneously and not all children need to be admitted to
hospital. It is reassuring if the child seems neurologically normal after the convulsion.
However, prolonged seizures should be stopped by appropriate acute treatment and if there