What is the difference between a seizure and a convulsion and how are they treated?
Seizures are sudden temporary changes in physical movement, sensation, or behavior caused by abnormal electrical impulses in the brain. Depending on how many muscles are affected by the electrical impulses, a seizure may cause sudden stiffening of the body or complete relaxation of the muscles, which can make a person appear to be paralyzed temporarily. Sometimes these seizures are referred to as “fits” or “spells.” The terms convulsion and seizure can be used interchangeably.
A convulsion that involves the whole body (sometimes called a "generalized tonic-clonic" or "grand mal" seizure) is the most dramatic type of seizure, causing rapid, violent movements and occasionally loss of consciousness. These sometimes can start with focal movements (those involving one specific part of the body) and progress to generalized movements (i.e., both sides of the body). Convulsions occur in about five out of every 100 people at some time during childhood. By contrast, "absence" seizures (previously called "petit mal" seizures) are momentary episodes with a vacant stare or a brief (one- or two-second) lapse of attention. These occur mainly in young children and may be so subtle that they aren’t noticed until they begin affecting schoolwork.
Febrile convulsions (seizures caused by high fever) occur in 3 or 4 out of every 100 children between six months and five years of age, but most often around twelve to eighteen months old. Children younger than one year at the time of their first simple febrile seizure convulsion have approximately a 50 percent chance of having another, while children over one year of age when they have their first seizure have about a 30 percent chance of having a second one. Nevertheless, only a very small number out of 100 children will go on to develop chronic seizures without a fever.
A febrile convulsion can cause reactions as mild as a rolling of the eyes or stiffening of the limbs, or as startling as a generalized convulsion with twitching and jerking movements that involve the whole body. Febrile convulsions usually last less than two or three minutes, and ordinarily the child’s behavior quickly returns to normal.
The term epilepsy is used to describe seizures that recur repeatedly over time without an acute illness (like fever) or brain injury. Sometimes the cause of the recurring seizures is known (symptomatic epilepsy), and sometimes it is not (idiopathic epilepsy).
Other similar disorders
Some children experience sudden episodes that might masquerade or imitate seizures, but are really not. Examples include breath holding, fainting (syncope), facial or body twitching (myoclonus), and unusual sleep disorders (night terrors, sleepwalking, and cataplexy). They may occur just once or may recur over a limited time period. Again, although these episodes may resemble epilepsy or true seizures, they are not, and they require quite different treatment.
Most seizures will stop on their own and do not require immediate medical treatment. If your child is having a convulsion, protect her from injuring herself by laying her on her side with her hips higher than her head, so she will not choke if she vomits.
If the convulsion does not stop within two or three minutes or is unusually severe (difficulty breathing, choking, blueness of the skin, having several in a row), call for 911 for emergency medical help. Do not leave your child unattended, however. After the seizure stops, call the pediatrician immediately and arrange to meet in the doctor’s office or the nearest emergency department. Also call your doctor if your child is on an anticonvulsant medication, since this may mean that the dosage must be adjusted.
Finding the cause
If your child has a fever, the pediatrician will check to see if there is an infection. If there is no fever and this was your child’s first convulsion, the doctor will try to determine other possible causes by asking if there is any family history of seizures or if your child has had any recent head injury. He will examine the child and also may order blood tests, pictures of the brain using computed tomography (CAT scan) or magnetic resonance imaging (MRI), or an electroencephalogram (EEG), which measures the electrical activity of the brain. Sometimes a spinal tap will be performed to obtain a specimen of spinal fluid that can be examined for some causes of convulsions such as meningitis, an infection of the lining of the brain. If no explanation or cause can be found for the seizures, the doctor may consult a pediatric neurologist, a pediatrician who specializes in disorders of the nervous system.
If your child has had a febrile convulsion, some parents may try controlling the fever using acetaminophen and sponging. However, these approaches do not prevent future febrile seizures, but only make the child comfortable. If a bacterial infection is present, your doctor will probably prescribe an antibiotic. If a serious infection such as meningitis is responsible for the seizure, your child will have to be hospitalized for further treatment. Also, when seizures are caused by abnormal amounts of sugar, calcium, or magnesium in the blood, hospitalization may be required so that the cause can be found and the imbalances corrected.
If epilepsy is diagnosed, your child usually will be placed on an anticonvulsant medication. When the proper dosage is maintained, the seizures can almost always be completely controlled. Your child may need to have her blood checked periodically after starting some medications to make certain there is an adequate amount present. She also may need periodic EEGs. Medication usually is continued until there have been no seizures for a year or two.
As frightening as seizures can be, it’s encouraging to know that the likelihood that your child will have another one drops greatly as she gets older. (Only 1 in 100 adults ever has a seizure.) Unfortunately, a great deal of misunderstanding and confusion about seizures still exists, so it is important that your child’s friends and teachers understand her condition. If you need additional support or information, consult with your pediatrician or contact your local or state branch of the Epilepsy Foundation.