What Is a Febrile Seizure?

Febrile seizures usually occur in children between the ages of 6 months and 5 years, though they’re most common between 12 and 18 months of age.

These convulsions happen in children experiencing a rapidly rising fever of 102°F (39°C) and above. However, febrile seizures can also occur at lower body temperatures.

The main factor contributing to the seizure is the rapid change in body temperature rather than the high fever itself. They usually happen when your child has an illness.

There are two types of febrile seizures: simple and complex. Complex febrile seizures last longer. Simple febrile seizures are more common.

The symptoms of febrile seizures vary based on the two types:

Simple febrile seizures

Symptoms of simple febrile seizure are:

• loss of consciousness
• shaking limbs or convulsions (usually in a rhythmic pattern)
• confusion or tiredness after the seizure
• no arm or leg weakness

Simple febrile seizures are the most common. Most last less than 2 minutes but can last as long as 15 minutes. Simple febrile seizures rarely happen more than once in a 24-hour period.

Complex febrile seizure

Symptoms of complex febrile seizure are:

• loss of consciousness
• shaking limbs or convulsions
• temporary weakness usually in one arm or leg

Complex febrile seizures last for more than 15 minutes. Multiple seizures may happen over a 30-minute period. They may happen more than once during a 24-hour time frame as well.

When a simple or complex febrile seizure occurs repeatedly, it’s considered a recurrent febrile seizure. Symptoms of recurrent febrile seizures include the following:

• Your child’s body temperature for the first seizure was lower.
• The next seizure happens within a year of the initial seizure.
• Your child has fevers frequently.

This type of seizure tends to occur in children under 15 months of age.

Febrile seizures generally happen when your child has an illness, but many times they occur before you realize your child is sick. That’s because they usually take place on the first day of an illness, so your child may not be showing any other symptoms yet.

There are several different causes for febrile seizures:

• A fever that occurs after immunizations, especially the MMR (mumps measles rubella) immunization, can cause febrile seizures. A high fever after immunizations most often occurs 8 to 14 days after your child has been given the immunization. However, this is very rare, and the benefits of the vaccine far outweigh the risks. Talk with your doctor if you have concerns.
• A fever that’s the result of a virus or a bacterial infection can cause febrile seizures. Roseola is the most common cause of febrile seizures.
• Risk factors, such as having family members who’ve had febrile seizures, will increase your child’s chance of having them.

While febrile seizures often don’t cause any lasting issues, there are important steps to take when your child has one.

Always contact a doctor or medical professional in the emergency department immediately following a seizure. The doctor will want to make sure your child doesn’t have meningitis, which can be serious. This is especially true for children under 1 year of age.

While your child is having a febrile seizure:

• Roll them onto their side.
• Don’t put anything in their mouth.
• Don’t restrict the movement of the convulsions or shaking.
• Move any objects that might harm them during the convulsions (furniture, sharp items, etc.).
• Place the child in a safe area on the floor to prevent falling injuries.
• Time the seizure.

After the febrile seizure ends, see a doctor or emergency medical professional.

Have your child take medication to lower their fever, like ibuprofen (Advil) if they’re over 6 months old or acetaminophen (Tylenol). Dose the medication based on your child’s weight.

Wipe their skin with a washcloth or sponge and room temperature water to cool them down.

Hospitalization is only required if your child has a more serious infection that needs to be treated. The majority of children don’t need any medication for a febrile seizure.

Treatment of recurrent febrile seizures includes all of the above plus taking a dose of diazepam (Valium) gel that’s administered rectally. You can be taught to give the treatment at home if your child has recurrent febrile seizures. Note that this medication can only be prescribed to your child by a doctor.

Children with recurrent febrile seizures have an increased chance of having epilepsy later in their lives.

Febrile seizures can’t be prevented, except in some cases of recurrent febrile seizures.

Reducing your child’s fever with ibuprofen or acetaminophen when they’re sick doesn’t prevent febrile seizures. Since the majority of febrile seizures have no lasting effects on your child, it’s normally not recommended to give any anti-seizure medications to prevent future seizures.

However, these preventative medications may be given if your child has recurrent febrile seizures or other risk factors.

Febrile seizures are normally nothing to worry about even though it can be frightening to see a child have one, particularly for the first time.

However, have your child seen by your doctor or another medical professional as soon as you can after your child has a febrile seizure. Your doctor can confirm that it was in fact a febrile seizure and rule out anything else that may need further treatment.

Contact a medical professional immediately if the following symptoms occur:

• neck stiffness
• vomiting
• difficulty breathing
• severe sleepiness

Your child will usually go back to normal activities soon after the seizure ends without further complications.