Febrile Seizures

Dr. Parang Mehta, MD.

Some children with fever give a terrifying experience to their parents.  Without warning, they become rigid, the eyes roll up, the limbs may move rhythmically, and froth appears at the mouth.  Sometimes, the child may pass stools or urine unknowingly.  After a few minutes, the cruel rigidity of the limbs relaxes, and the child falls into a deep sleep.

What is this thing?

Febrile seizures are, quite simply, seizures caused by fever.  They occur in 3-4% of all children.  The condition for calling them febrile seizures is that they are associated with fever, and not associated with any disease of the brain or its coverings.  The important thing is, they are not a form of epilepsy, and most children prone to febrile seizures do not develop epilepsy.

Febrile seizures are triggered off by fever in children between the ages of 6 months and six years.  Sometimes, the fever is brought to notice by the seizure.  Occasionally, fever follows the seizure.  We don't know why some children react thus to fever, but we do know that these seizures are usually harmless, though scary.

Will it happen again?

Will a child with one febrile seizure get another?  If a child was very young at the time of the first seizure, and one of the parents also had such seizures, the risk of recurrence is high.  If the child was less than a year old at time of the first febrile seizure, there is a 50% probability of more seizures with future fever.  The risk is about half of this in children who have their first seizure beyond infancy.

In children who are otherwise normal, febrile seizures almost never lead on to epilepsy.  There is no need to treat these children with anti epileptic drugs, or do tests like the EEG.

What should you do if you a see a child having a febrile seizure?  Hold her gently and try to avoid injury.  Loosen clothing, so that breathing is easy.  Turning her onto one side will allow saliva to flow out, so that breathing is not obstructed.  Don't try to force anything into the mouth, because that is dangerous.  Once the seizure is over, or if it lasts more than a few minutes, take the child to hospital immediately.

Treatment

How are febrile seizures treated?  The most important thing is to ensure the absence of serious diseases like meningitis, cerebral malaria, and encephalitis, which also present with fever and seizures.  Your doctor may want to admit the child to hospital and run some tests, including a lumbar puncture.  Once a diagnosis of febrile seizure is made, all that is required is to keep the fever low to prevent the triggering of another seizure, and the treatment of the cause of the fever.

Should we try to prevent seizures in a child who has had one? Diazepam is a drug that can be given by mouth whenever the child has fever.  It is effective, but has many side effects.  Besides, seizures often occur at the onset of fever, before diazepam can be given.  Drugs like phenobarbitone and valproate can be given regularly over a prolonged period to prevent febrile seizures, but they have significant side effects.  Most experts feel that drug therapy is unjustified for an essentially harmless condition.

Though febrile seizures are quite benign, each episode should prompt a full evaluation by your doctor.  A child may have had three febrile seizures from which she recovered quickly and easily, but the fourth episode of convulsions and fever may be a serious illness, not febrile seizures.

Last Revision: February 16, 2016

Febrile Seizures and Epilepsy

This is the main fear when a child has febrile seizures.  Will he go on to develop epilepsy as an adult? The risk for an otherwise normal child is approximately 1% -- about the same as for children who do not have febrile seizures.  But certain factors increase the risk.

Children with several of these factors have a risk factor of later epilepsy as high as 9%.

Seizures, Fever, and Meningitis