Febrile seizures

Causes

Febrile seizures occur most often in otherwise healthy children between ages 9 months and 5 years. Toddlers are most commonly affected. Febrile seizures often run in families.

Most febrile seizures occur in the first 24 hours of an illness and may not occur when the fever is highest. Ear infections or any cold or viral illness may trigger a febrile seizure.

Symptoms

A febrile seizure may be as mild as the child's eyes rolling or limbs stiffening. A simple febrile seizure stops by itself within a few seconds to 10 minutes. It is often followed by a brief period of drowsiness or confusion.

Febrile seizures may begin with the sudden tightening (contraction) of muscles on both sides of a child's body.

• The child may cry or moan.
• The muscle tightening may last for several seconds, or longer.
• The child will fall, if standing, and may pass urine.
• The child may vomit or bite the tongue.
• Sometimes children do not breathe, and may begin to turn blue.
• The child's body may then begin to jerk rhythmically. The child will not respond to the parent's voice.

A seizure lasts longer than 15 minutes, is in just one part of the body, or occurs again during the same illness is not a normal febrile seizure.

Exams and Tests

The health care provider may diagnose febrile seizure if the child has a grand mal seizure but does not have a history of seizure disorders (epilepsy). In infants and young children, it is important to rule out other causes of a first-time seizure, especially meningitis.

In a typical febrile seizure, the examination usually is normal, other than symptoms of the illness causing the fever. Typically, the child will not need a full seizure workup, which includes an EEG, head CT, and lumbar puncture (spinal tap).

Further testing may be needed if:

• The child younger than 9 months or older than 5 years
• The child has a brain, nerve, or developmental disorder.
• The seizure was confined to one part of the body.
• The seizure lasted longer than 15 minutes.
• The child had more than one febrile seizure in 24 hours.
• The child has abnormal findings when examined .

Treatment

During the seizure, leave your child on the floor.

• You may want to slide a blanket under the child if the floor is hard.
• Move him only if he is in a dangerous location.
• Remove objects that may injure him.
• Loosen any tight clothing, especially around the neck. If possible, open or remove clothes from the waist up.
• If he vomits, or if saliva and mucus build up in the mouth, turn him on his side or stomach. This is also important if it looks like the tongue is getting in the way of breathing.

Do NOT try to force anything into his mouth to prevent him from biting the tongue, as this increases the risk of injury. Do NOT try to restrain your child or try to stop the seizure movements.

Focus your attention on bringing the fever down:

• Insert an acetaminophen suppository (if you have some) into the child's rectum.
• Do NOT try to give anything by mouth.
• Apply cool washcloths to the forehead and neck. Sponge the rest of the body with lukewarm (not cold) water. Cold water or alcohol may make the fever worse.
• After the seizure is over and your child is awake, give the normal dose of ibuprofen or acetaminophen.

After the seizure, the most important step is to identify the cause of the fever.

Meningitis causes less than 0.1% of febrile seizures. It should always be considered, especially in children less than 1 year old, or those who still look ill when the fever comes down.

Outlook (Prognosis)

The first febrile seizure is a frightening moment for parents. Most parents are afraid that their child will die or have brain damage. However, simple febrile seizures are harmless. There is no evidence that they cause death, brain damage, epilepsy, a decrease in IQ, or learning problems.

Most children outgrow febrile seizures by age 5.

Few children have more than three febrile seizures in their lifetime. The number of febrile seizures is not related to future risk of epilepsy.

Children who would develop epilepsy anyway will sometimes have their first seizures during fevers. These seizures most often do not appear like a typical febrile seizure.

When to Contact a Medical Professional

Children should see a doctor as soon as possible after their first febrile seizure.

If the seizure is lasting several minutes, call 911 to have an ambulance bring your child to the hospital.

If the seizure ends quickly, drive the child to an emergency room when it is over.

Take your child to the doctor if repeated seizures occur during the same illness, or if this looks like a new type of seizure for your child.

Call or see the health care provider if other symptoms occur before or after the seizure, such as:

• Abnormal movements
• Agitation
• Confusion
• Drowsiness
• Nausea
• Problems with coordination
• Rash
• Sedation
• Tremors

It is normal for children to sleep or be briefly drowsy or confused right after a seizure.

Alternative Names

Seizure - fever induced

References

Mikati MA. Febrile seizures.In: Kliegman RM,Behrman RE, Jenson HB, Stanton BF, eds.Nelson Textbook of Pediatrics.19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 586.1.

Update Date: 2/11/2010

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.