Epilepsy is a condition that affects the brain and causes repeated seizures.
The cells in the brain, known as neurons, conduct electrical signals and communicate with each other in the brain using chemical messengers. During a seizure, there are abnormal bursts of neurons firing off electrical impulses, which can cause the brain and body to behave strangely.
The severity of seizures can differ from person to person. Some people simply experience an odd feeling with no loss of awareness, or may have a "trance-like" state for a few seconds or minutes, while others lose consciousness and have convulsions (uncontrollable shaking of the body).
Some people may only have a single seizure at some point during their life. If they do not have a high risk of having further seizures, they would not be regarded as having epilepsy.
Signs and symptoms
Characteristics of seizures vary and depend on where in the brain the disturbance first starts, and how far it spreads. Temporary symptoms occur, such as loss of awareness or consciousness, and disturbances of movement, sensation (including vision, hearing and taste), mood, or other cognitive functions.
People with seizures tend to have more physical problems (such as fractures and bruising from injuries related to seizures), as well as higher rates of psychological conditions, including anxiety and depression. Similarly, the risk of premature death in people with epilepsy is up to 3 times higher than the general population, with the highest rates found in low- and middle-income countries and rural versus urban areas.
A great proportion of the causes of death related to epilepsy in low- and middle-income countries are potentially preventable, such as falls, drowning, burns and prolonged seizures.
Epilepsy is not contagious. The most common type of epilepsy, which affects 6 out of 10 people with the disorder, is called idiopathic epilepsy and has no identifiable cause.
Epilepsy with a known cause is called secondary epilepsy, or symptomatic epilepsy. The causes of secondary (or symptomatic) epilepsy could be:
- Brain damage from prenatal or perinatal injuries (e.g. a loss of oxygen or trauma during birth, low birth weight),
- Congenital abnormalities or genetic conditions with associated brain malformations,
- A severe head injury,
- A stroke that restricts the amount of oxygen to the brain,
- An infection of the brain such as meningitis, encephalitis, neurocysticercosis,
- Certain genetic syndromes,
- A brain tumor.
Epilepsy is usually difficult to diagnose quickly. In most cases, it cannot be confirmed until you have had more than one seizure.
It can be difficult to diagnose because many other conditions, such as migraines and panic attacks, can cause similar symptoms.
If you have had a seizure, you will be referred to a specialist in epilepsy, normally a neurologist (a doctor who specialises in conditions affecting the brain and nervous system).
The doctor will ask about your medical and personal history and whether you use any medicines, drugs or alcohol.
The doctor may be able to make a diagnosis of epilepsy from the information you give, but they might run further tests such as an electroencephalogram (EEG) or magnetic resonance imaging (MRI) scan.
However, even if these tests don't show anything, it is still possible that you have epilepsy.
Treatment for epilepsy is used to control seizures, although not everyone with the condition will need to be treated.
It may sometimes be possible to control your epilepsy solely by avoiding things that trigger your seizures, such as sleep deprivation and alcohol.
While some people may need to be treated for the rest of their lives, this is not always the case. Sometimes people have epileptic seizures at one stage in their life, only for them to become less frequent or disappear as they get older. This is more common if seizures first occur in childhood or early adulthood.
Anti-epileptic drugs (AEDs) are usually the first choice of treatment for epilepsy. About 70% of people with the condition are able to control their seizures with AEDs.
Usually, AED treatment will not begin until after you have had a second seizure because a single seizure is not necessarily a reliable indicator that you have epilepsy.
In some cases, treatment may begin after a first seizure if:
- An electroencephalogram (EEG) shows brain activity associated with epilepsy
- A magnetic resonance imaging (MRI) scan shows damage to the brain
- You have a condition that has damaged the brain, such as a stroke
For some people, brain surgery may be an option. However, this is only the case if removing the area of the brain where epileptic activity starts would not cause damage or disability. If successful, there is a chance your epilepsy will be cured.
If surgery is not an option, an alternative may be to implant a small device under the skin of the chest. The device sends electrical messages to the brain. This is called vagus nerve stimulation.
Sometimes, a special diet is used for children whose seizures are difficult to control and do not respond to treatment with medication.