Epilepsy

This month, in the fourth of this new series of factsheets designed to broaden your clinical knowledge we look at epilepsy.

AROUND 2% OF THE POPULATION suffers from epilepsy, which untreated can cause seizures, or fits. Epilepsy usually starts between the ages of three months and the teens. Around 60 per cent of children with epilepsy grow out of it, but for most other people, it can be controlled with medication.

What is epilepsy? Epilepsy is characterised by seizures, sometimes called fits or convulsions. These occur when some of the nerve cells in the brain become overactive, and fire off uncontrolled random signals. Some people have one seizure and then never have another again. But people who experience repeated seizures – whether once a year, or several times a day – have epilepsy. The cause of epilepsy is not known, but it’s generally thought to be the result of a chemical imbalance in the brain. People can be more at risk if they have had a stroke, head injury, meningitis or if they have a history of drug or alcohol abuse. Epilepsy sometimes runs in families, and can be the result of a brain injury at birth or a brain tumour. In most cases, though, it is not known why some people get epilepsy and others don’t.

SeizuresThe main symptom of epilepsy is repeated seizures. Most people have no other symptoms, and live perfectly normal lives. Seizures may come on without warning, although they can be triggered by flashing lights. They are sometimes preceded by an “aura”, which may be a strange smell, taste or feeling. There are different kinds of seizures. Some people experience just a fleeting loss of awareness. Others lose consciousness and suffer stiffening or jerking movements in their body. Seizures can last just a few seconds, or may go on for some minutes, and can be barely noticeable or quite traumatic. Types of epilepsy There are several different types of epilepsy, each with different symptoms.

Primary generalised epilepsyIn this kind of epilepsy, also known as grand mal epilepsy, nerve cells in both sides of the brain become overactive at the same time. Seizures usually last for about five minutes, and can be alarming. In a grand mal seizure, people are likely to experience some or all of the following:

Absence seizuresAbsence seizures, also called petit mal epilepsy, is not as alarming as grand mal. There may be a loss of consciousness, or more often just a loss of awareness, but this kind of seizure doesn’t involve falling down or experiencing involuntary jerking movements. In fact, people may just look as if they are daydreaming. This kind of seizure is most common in children aged between five and nine. Most grow out of them by the time they are 13. For more information, see the BUPA factsheet, Epilepsy in children.

Juvenile myoclonic epilepsy During a juvenile myoclonic epileptic seizure, the hands, arms or whole body will start jerking, but the person doesn’t lose consciousness or awareness. This type of epilepsy usually develops in late childhood. It tends to run in families.

Temporal lobe epilepsy Temporal lobe epilepsy has quite different symptoms. They include:

DiagnosisTo diagnose epilepsy, a doctor will need a detailed description of the seizures – family members or friends can often help with this. The doctor may then arrange for some tests. These can include an EEG (electroencephalogram), a brain scan – either CT (computerised tomography) or MRI (magnetic resonance imaging) and blood and urine tests.

TreatmentThere is no cure for epilepsy, but drug treatment can control the seizures in around 70 per cent of people. These drugs sometimes have side-effects, though, such as drowsiness or a rash. If someone who has had epilepsy doesn’t have a seizure for two years, their doctor may suggest they come off the medication (or reduce the dose). Some children with particular forms of epilepsy are recommended a “ketogenic” diet – one high in fat and low in carbohydrates. Brain surgery may be appropriate for some people with severe and disabling epilepsy that is not improved after trying several different anti-epileptic drugs over three to five years.

Managing epilepsyPeople with epilepsy may need to avoid certain activities or jobs where it could be dangerous to have a seizure – most obviously, things like flying a plane, but also, for example, operating certain machinery, riding a bicycle in busy traffic, or swimming alone. People who are diagnosed with epilepsy cannot drive until their doctor confirms that their seizures are under control – usually no less than a year since their last seizure. If a child has epilepsy, it is important to ensure he or she doesn’t get too tired. And older children and adults may benefit from relaxation and anti-stress exercises. It’s also a good idea for someone with epilepsy to carry a card, necklace or bracelet which says that they have epilepsy. Family, friends, teachers and colleagues should be told what to do in the event of a seizure.