Epilepsy (also known as seizure disorder) is a neurological condition with symptoms which vary from a momentary lapse of attention to convulsions. What it is has been understood. What causes it is often not understood. Epilepsy was one of the first brain disorders to be described and its history goes back some 3000 years when it was first mentioned in Babylon. The word epilepsy is derived from the Greek word for "attack." It was once thought that people who had epilepsy were being visited by demons or gods. However in 400 B.C., the early physician Hippocrates suggested that epilepsy was a disorder of the brain.

A seizure disorder includes any condition in which there are repeated episodes of seizures of any type. Damage to brain cells can disrupt the normally smooth-running pattern of electrical activity in the brain by causing an electrical overload. This can create a seizure, which causes a sudden change in the individual's consciousness and/or change in motor activity. Epilepsy (idiopathic seizure disorder) is a term used when the seizure disorder has no identifiable cause such as brain disease. A seizure disorder affects about 0.5% of the population, and may affect people of any age.(1) The symptoms, frequency, intensity, and types of seizures vary greatly from person to person. Those whose condition is controlled by medication may not experience seizures at all.

In many cases, the cause of epilepsy is unknown.(2) It can occur as a result of an infection, head injury, brain tumor, hydro-cephalus, toxic reaction to drugs and alcohol, or other conditions which injure the brain and damage brain cells.(3, 4) Genetic factors may contribute to the development of a seizure disorder, but are not a primary cause.(5) It may also be associated with other neurological conditions such as cerebral palsy. The cause of the seizure correlates to some extent with how old the person is when the first seizure occurs. In some people, seizures may be triggered by hormone changes such as pregnancy or menstruation. They may also be triggered by illness or by sensory stimuli such as lights, sounds, and touch. In many cases, no trigger is found for the seizures. Though no direct link to seizures has been confirmed, people who have seizures have been shown to have low blood levels of vitamin A, vitamin C and vitamin E.(6)

Seizures may occur in a generalized form (affecting all or most of the brain) or in a partial form. Epilepsy is typically generalized (except in some cases that develop in childhood and have a specific focus). Generalized seizures include variations of what are referred to as generalized tonic-clonic seizures and petit mal seizures. Partial seizures include focal seizures (during which the person remains alert but there are abnormal movements or sensations) and partial complex seizures (during which the abnormal movement or sensation is accompanied by changes in consciousness).