Epilepsy is not strictly an isolated medical condition in itself, rather it is a symptom of other conditions that have affected the brain.

Epilepsy can have a number of causes. For example, it is sometimes caused by brain damage, either through injury or infection, or it may be caused by stroke, cerebral palsy, tumors, and problems during birth.

However, in one third of epilepsy cases, no known cause can be identified. These sorts of cases are known as idiopathic epilepsy.

The brain is a delicate mix of neurons (brain cells), electrical impulses and special chemicals known as neurotransmitters - much like a living computer - so any damage has the potential to disrupt the working of the brain and cause seizures.

Conditions that can cause epilepsy include:

• strokes,
• cerebral tumors (an abnormal growth of cells in the brain),
• conditions that affect the structure of the brain, such as cerebral palsy,
• drug and alcohol abuse,
• birth defects,
• problems during birth which cause a baby to be deprived of oxygen, such as the umbilical cord getting twisted or compressed during labor,
• infectious conditions that can damage the brain, such as meningitis, and
• head injuries.

In some people, epilepsy may be caused by problems with their genes. Researchers think that defects in certain genes can cause special proteins known as ion channels to malfunction.

Ion channels help transmit tiny amounts of electricity from one cell to another. So researchers believe that these malfunctioning ion channels could disrupt the electrical impulses of the brain and call seizures.

More research is required to find out exactly what genes are involved, who is at risk, and how to treat the condition.

Epilepsy triggers

Many people with epilepsy find that certain circumstances, or substances, can trigger a seizure. These triggers include:

• stress,
• lack of sleep,
• alcohol, particularly if a large amount is drunk in a short time (binge drinking),
• illegal drugs- cocaine, amphetamines, ecstasy, and any opiate-based drug, such as heroin, methadone, or codeine,
• health conditions that cause a high temperature (fever), and
• flashing lights- this is actually quite a rare trigger, affecting only 5% of people with epilepsy.

Some women may find that they are more prone to having seizures just before the start of their period. This is because the hormones released by the body during the time can change the chemical composition of the brain, making seizures more likely.

Also the changes in mood many women experience before their period - premenstrual tension (PMT) - can make them feel stressed and anxious, which again increases the chance of a seizure.