Epilepsy Frequently Asked Questions (FAQs)

What Causes Epilepsy?

To understand how epilepsy arises, we must briefly outline how the brain functions normally. The brain consists of millions of nerve cells, or neurones, and their supporting structure. Each neurone maintains itself in an electrically charged state. It receives electrical signals from other neurones, and passes them on to others. What actually happens is that a tiny quantity of a special neurotransmitter substance is released from the terminals of one neurone. This chemical excites an electrical response in the nuerone next in the chain, and so the signal moves onward.

All the functions of the brain, including feeling, seeing, thinking and moving muscles depend on electrical signals being passed from one neurone to the next, the message being modified as required. The normal brain is constantly generating electrical rhythms in an orderly way. In epilepsy this order is disrupted by some neurone discharging signals inappropriately. There may be a kind of brief electrical "storm" arising from nuerones that are inherently unstable because of a genetic defect (as in the various types of inherited epilepsy), or from neurones made unstable by metabolic abnormalities such as low blood glucose, or alcohol. Alternatively, the abnormal discharge may come from a localised area of the brain (this is the situation in patients with epilepsy caused by head injury, or brain tumour).

Can anyone have Epilepsy?

Virtually everyone can have a seizure under the right circumstances. Each of us has a brain seizure threshold which makes us more or less resistant to seizures. Seizures can have many causes, including brain injury, poisoning, head trauma, or stroke; and these factors are not restricted to any age group, sex, or race and neither is Epilepsy

Does Epilepsy strike at any particular age?

A Epilepsy can strike anyone at any age. But, as the table below (adapted from an EFA publication) shows, some age groups are more susceptible than others.

Age groups First seizures occurring - %

• 0-9 - 47 %
• 10-19 - 30 %
• 20-29 - 13 %
• 30-39 - 6 %
• 40+ - 4 %

Age group by % all first seizures occurring in each age group. Most people who develop seizures during their earlier years tend to experience a reduction in the intensity and frequency of their seizures as they grow older. In many cases the Epilepsy will disappear completely. 50% of all cases develop before 10 years of age.

What is a seizure?

The best available classification of seizures is that proposed by the International League Against Epilepsy ("seizure" is an alternative term for "epileptic attack"). It starts by dividing seizures into partial seizures, where the abnormal electrical discharge originates from one specific area of the brain, and generalised seizures, where the whole brain is involved. What makes it a little confusing is that a partial seizure may occasionally go on to become generalised, if the epileptic discharge originating in one area of the brain is strong enough to then spread to the whole brain. However, even if the situation of a partial seizure progressing to become generalised, with complete loss of consciousness, convulsions, etc., the initial symptoms will be prominent, and will distinguish it from other forms of generalised epilepsy, where the whole brain is involved from the outset.

How long does a seizures last?

Depending on the type of seizure, they can last anywhere from a few seconds to several minutes. In rare cases, seizures can last many hours. For example, a tonic-clonic seizure typically lasts 1-7 minutes. Absence seizures may only last a few seconds, while complex partial seizures range from 30 seconds to 2-3 minutes. "Status Epilepticus" refers to prolonged seizures that can last for many hours, and this can be a serious medical condition. In most cases, however, seizures are fairly short and little first aid is required.