The following discussion is for general informational purposes only and is not meant to provide the reader with specific medical advice. Please consult with your personal physician, or with a neurologist, for specific advice, guidance and information regarding your particular circumstances.
When the brain is functioning typically, brain cells communicate with one another by way of seemingly random electrical activity, in order to control the body's movements.
A seizure is produced when the electrical activity of thousands to millions of brain cells fire simultaneously. Epilepsy is the disorder primarily characterized by the tendency to have recurrent seizures.
A single seizure does not necessarily suggest that one has epilepsy. 300,000 people have a first seizure each year and 200,000 new cases of epilepsy are diagnosed yearly. Approximately 2.7 million Americans have epilepsy and, over a lifetime, approximately 10% of Americans will have at least one seizure.
In 70% of epilepsy cases, no cause is ever found. Some possible causes of seizures include head injury, brain tumors, stroke, inherited brain disease, disorders causing lack of oxygen to the brain, toxic substances, high fevers, degenerative diseases and brain infections.
Seizures come in multiple types. The most common of these include complex partial, tonic-clonic (generalized convulsions; "grand mal") and absence ("petit mal"). With each of these seizure types, most people have no recollection of the events associated with the seizure.
Complex partial seizures occur when the abnormal electrical activity is confined to one region of the brain. This results in alteration of sensation and/or behavior. This may include uncontrolled movements of one body part, unresponsiveness, staring, facial movements, confusion or, rarely, aggressive behavior. These seizures may be preceded by an "aura", which may include sudden onset of fear, deja vu, unusual odors or tastes, nausea or stomach discomfort. These events tend to last no more than 5 minutes.
Generalized tonic-clonic seizures reflect involvement of the entire brain at once. These include immediate loss of consciousness with associated stiffening of all muscles, followed by alternating periods of flexion and extension of muscles. This is frequently accompanied by involuntary crying out, falls, foaming at the mouth, inability to breathe for a brief period and possible tongue biting. These seizures generally last no more than 90 seconds to 2 minutes.
Absence seizures are generally brief episodes of loss of consciousness, including staring and, occasionally lip-smacking. They may resemble day-dreaming to the outside observer and are generally very short, lasting only seconds.
The most appropriate approach to a seizure is to ensure that the patient remains safe and to allow the seizure to run its course. A seizure lasting more than 10 minutes should be evaluated emergently.
The diagnosis of seizures is largely dependent upon a detailed history, including an accurate account of what happened at the time of the apparent seizure. Epilepsy is determined when an individual has had 2 or more seizures. This diagnosis may be aided by the use of electroencephalography (EEG) to evaluate the brain's electrical activity and magnetic resonance imaging (MRI) to evaluate the brain for structural abnormalities.
Patients with epilepsy are generally maintained on one of ten major anticonvulsant medications. These medications are started and altered as necessary to maintain seizure freedom and freedom from side effects. Anti-convulsant therapy tends to be life-long.
For patients who don't respond to medications, two surgical modalities exist. A Vagal Nerve Stimulator (VNS) is a device implanted in the chest, with wires which track toward the brain, producing electrical signals which have been shown to decrease the risk of seizures. A very small number of patients may be candidates for epilepsy surgery, in which the dysfunctional area of the brain producing the seizures is removed.
Further information may be obtained from the Epilepsy Foundation of America: