Summary: Febrile seizures (seizures with fever) are common, frightening and almost always benign. This chapter explains what these are and how to prevent them. Aggressive fever control is the most effective means of preventing febrile seizures. Distinguishing a benign febrile seizure from epilepsy is important, but this cannot be easily done early on in most instances.

A seizure and a convulsion mean roughly the same thing. Some people call these "fits". A seizure due to fever is called a "febrile seizure" or "febrile convulsion". "Febrile" is a fancy word for fever.

A child with a seizure is frightening. A convulsing (seizing) child usually has the following appearance:
. . . . . a. Eyes rolled up.
. . . . . b. Body, arms and legs are stiff and slowly jerking violently.
. . . . . c. Not breathing well so they may become blue.
. . . . . d. Not responding and not crying.

Since this is very frightening, most parents instinctively call 911. A febrile seizure is one of the most common childhood events that results in a call for an ambulance.

Although this is very scary, febrile seizures are called "benign febrile seizures" because their outcome is almost always benign. Specifically, there is no brain damage that results from a benign febrile seizure. How can these be distinguished from epilepsy? Epilepsy is a condition in which seizures recur; in other words, there is a tendency for the patient to have seizures. Epilepsy seizures can often occur with fever which makes it possible that a febrile seizure could represent epilepsy. However, if a seizure fits the following characteristics, it is most likely a benign febrile seizure rather than epilepsy. Febrile seizures are very common; much more common than epilepsy.

Criteria (characteristics) for benign febrile seizures:
. . . . . 1. Age 6 months to 6 years.
. . . . . 2. Seizure is generalized (all parts of the body are involved, rather than just half the body or one part of the body.
. . . . . 3. Seizure is brief (less than 15 minutes, but almost always less than 3 minutes).
. . . . . 4. Fever is present (greater than 39 degrees C or 102 degrees F).
. . . . . 5. After the seizure, the child may be drowsy, but there should be no loss of function; in other words, their ability to move all parts of their body is still present.
. . . . . 6. An EEG is normal.

Febrile seizures occur in young children, but NOT in newborns. Infants less than 5 months of age with a seizure are more likely to have something wrong with the brain. Most febrile seizures occur in children less than 20 months of age, but febrile seizure can occur in children up to 6 years, and some experts say 7 years old.

A generalized seizure (the entire body is convulsing) is more scary to watch than a partial seizure (only part of the body is convulsing), but generalized seizures are more often due to less serious causes. Partial seizures are more likely to be due to brain tumors, stroke and brain infection. These are serious conditions which often result in brain damage. Thus, a generalized seizure is actually less serious in most instances.

Although febrile seizures can be up to 15 minutes, nearly all febrile seizures are actually about 1 or 2 minutes. I have witnessed several of these in the ER because so many children come to the ER with fever, that every once in a while, the febrile seizure just happens to occur in the ER instead of at home. All the febrile seizures I have witnessed have lasted less than 2 minutes. However, this is a stressful period for most parents and it may be difficult to recall the true duration of the seizure. When I ask most parents how long they think the seizure was, I often get a reply of 15 minutes. But when I ask them to think about it again, they actually believe that the seizure duration was more like 2 to 3 minutes. When something this frightening is occurring, it is difficult to be certain about how long it actually lasted. Its duration tends to be overestimated. Long seizures are less likely to be benign febrile seizures.

Fever that is at least 39 degrees C or 102 degrees F should be present when the seizure occurs. If the fever and the seizure are not present together, then this does not fit the usual pattern of a febrile seizure. The higher the fever, the greater the risk of a seizure, but not all high fevers result in seizures. The occurrence of a seizure is unpredictable. Some experts believe that it is not a high fever that causes a seizure, but rather a rapid rise in the temperature causes the seizure. This is only an opinion and it is difficult to be certain about why these occur. Regardless of the cause, a fever must be present for it to be a febrile seizure. Seizures that occur without fever are more likely to be epilepsy.

A seizure can be thought of as an electrical storm in the brain resulting in multiple short circuits. After this electrical storm in the brain, the brain's function is temporarily weak and patients are very drowsy because of this. There is recovery generally within about 30 minutes and most patients are back to their normal degree of alertness. Febrile seizures are followed by these episodes of drowsiness as well. In epilepsy, some epileptic seizures are followed by temporary paralysis of one or more parts of the body. This resolves and normal function is generally restored within several hours. This type of temporary paralysis following a seizure should NOT be present with a febrile seizure.

An electroencephalogram (EEG) is a test of the brain waves. Wires are placed on the scalp using a glue gel (no needles are involved). These wires measure the electrical activity of the underlying brain within the skull as the electrical signals reach the skin. Brain waves have a characteristic shape best described as gentle waves, that change with different states of mind. In epilepsy, the brain's electrical activity shows spiking signals which show more intense electrical events. These spikes are present in the brain even if the patient appears to be normal and is not convulsing. Another sign of epilepsy on an EEG is a slowing of the usual electrical wave rhythms. An EEG can usually distinguish between epilepsy and febrile seizures. This is one of the most important questions for parents who want to know if their child is likely to have another seizure or not. Unfortunately, after any type of seizure, slowing normally occurs, therefore, an EEG done soon after a seizure can be misleading. It is best to do an EEG about 1-2 months after a seizure because that is when epilepsy and febrile seizures can be best distinguished on the EEG. By this time, an EEG is normal in febrile seizures and it is usually abnormal in epilepsy.

An EEG is often NOT done in most cases because the EEG test is difficult to do. Realize that most children with febrile seizures are only 1-2 years old. These wires must be glued to their scalp, then they must stay still for about 30 to 45 minutes. This test is done in the hospital during the day when your child is not likely to want to stay still. Young patients undergoing an EEG must be sedated with a sleeping medication, which adds a small amount of risk to the procedure. Suffice it to say that an EEG is difficult to do and since 1-2 months must pass before the EEG is done, by this time, the pediatrician or family physician generally knows whether the child has done well, or whether more seizures have occurred. If the child is doing well, as in most instances, the need for an EEG becomes less necessary since the likelihood of epilepsy is low. Thus, while an EEG can be very useful in helping to answer a parent's most burning question (epilepsy versus benign febrile seizures), an EEG is usually not done for the reasons described.

The treatment for seizures largely depends on fever control which is described in the previous chapter. If fever can be prevented, febrile seizures will not occur. Unfortunately, it might be difficult to predict when a child might develop a fever and thus, medication cannot always be given in time to prevent a fever from developing. Once a seizure begins, it will usually stop on its own without any special treatment. Refer to the specific set of instructions at the end of this chapter.

Anti-seizure medications have been used in the treatment of febrile seizures, but most experts would agree that these should only be used if the seizures are frequent. Phenobarbital is an anti-seizure medication that has been used for febrile seizures. Phenobarbital is also a sedative, so children often become drowsy when taking this medication. Phenobarbital takes effect slowly, so for it to be effective in preventing a febrile seizure, it must be in the body at a high enough level for a good period of time before the seizure. This is unlikely to be helpful since usually, the onset of the initial fever spike cannot be easily predicted. Patients with frequent febrile seizures have these because they are particularly sensitive to high fevers and/or their fevers are difficult to predict and more difficult to control. Most experts recommend that when phenobarbital is to be used to control frequent febrile seizures, it should be given every day regardless of whether the child is ill or not. This is the only way to be certain that the phenobarbital level will be high enough to prevent a seizure when an unpredictable fever spike occurs. Since phenobarbital causes some drowsiness, it becomes difficult to justify a medication which causes such side effects to prevent a condition which is intermittent and benign (febrile seizures).

Valium, also known as diazepam, is a sedative which also has anti-seizure properties with a faster onset than phenobarbital. More recently, diazepam has been recommended for children with frequent febrile seizures. Diazepam can be given with the initial onset of fever to prevent febrile seizures initially until the fever can be controlled. However, if the seizure occurs with the initial fever spike, a parent will not be able to give the diazepam in time. While this sounds like an effective treatment, it is only used for patients with frequent febrile seizures.

The treatment with the least amount of side effects is aggressive fever control. This will work for most children with febrile seizures.

The section below comes from an instruction sheet that I wrote for parents whose children come to the emergency room with a febrile seizure.

Febrile Seizure (Convulsion with fever):

1. Seizure, convulsion, and "fit" all mean the same thing.

2. When this occurs with fever, this is usually a febrile seizure.

3. Although it is very frightening, it is usually not serious.

4. Febrile seizures are usually short and cause no long term brain damage.

5. About one in four children may have a second seizure before age 6 years. It is unlikely that another seizure will occur soon as long as the fever is controlled. Simple febrile seizures are usually outgrown by age 6 years.

6. An EEG (a test of the brain waves to see if it is prone to seizures) is most accurate if done 1-2 months after a seizure. This can be discussed with your physician.

Treatment:

1. The most important treatment is aggressive fever control. Follow the fever control instructions.

2. Most important: Do not dress your child in warm clothes during an illness. It is common to believe that it is important to keep children warm when they are sick, but if they have fever, this means that their body is too hot. Wearing lots of clothes will make the body hotter and another seizure may occur.

3. To prevent another seizure from occurring the next time your child becomes ill, start the fever control instructions as soon as there is any symptom of illness.

IF A SEIZURE OCCURS:

1. Keep calm.

2. Lay your child down on his/her side in a safe place. Turn their head and body to the side to allow vomit and saliva to come out of the mouth instead of going down into the lungs.

3. Never force anything into the child's mouth. Never try to open clenched jaws.

4. During the seizure, blueness around the face may occur. Normal color will return when the seizure stops and breathing returns.

5. Time how long the seizure lasts and observe what the seizure looks like. This is important information for the doctor.

6. If the seizure stops in less than 3 minutes, call your doctor.

7. If the seizure is longer than 3 minutes or there is one seizure after another, call 911.

There are many misconceptions regarding seizures. Some believe that during a seizure, you must pry open their mouth to prevent them from swallowing their tongue. It's not possible to swallow your tongue, but the tongue can block the airway. During a generalized seizure, it is usually not possible to open their mouth, because the jaw is clenched closed. The jaw muscles are very strong and it may be impossible to pry open someone's mouth. Using a metal object such as a spoon or fork will likely cause injury to the mouth or result in broken teeth. Finger tips have been severely bitten when trying to grab the tongue of a child having a seizure.

Instead of trying to open their mouth, it would be best to position a seizing child on their side. This way, saliva and emesis (vomit) will come out of the mouth instead of going down into the lungs. The tongue will fall to the side so it won't block breathing.

When to call 911 is controversial. Most febrile seizures stop within 2 minutes. Brief seizures are not harmful, but long seizures (for example, 30 minutes or more) can cause brain damage. During a seizure, breathing is very shallow, which is why they often turn blue in the face (cyanosis due to lack of oxygen). Think of a short seizure as similar to holding your breath for 2 minutes; no brain damage results from this. But a long seizure can have serious consequences if the brain is starved of oxygen for too long. Thus, if a seizure has lasted longer than 3 minutes, it is possible that this seizure may last for a while. 911 should be called because they can administer oxygen and medication to stop the seizure.