What is epilepsy? Causes, symptoms and diagnosis

Epilepsy is a condition that affects the brain and causes repeated seizures. The condition can start at any age and there are many different types.

Not everyone who has a seizure will have epilepsy. The condition is usually diagnosed when a person:

• Has more than one seizure that were not caused by something temporary (like a fever or low blood sugar)
• Has one seizure and the doctor thinks it is very likely to happen again, based on your medical history and test results

A seizure is when our body does something we can’t control.

Electrical activity is happening in our brain all the time as our brain cells send messages to each other. A seizure happens when there is a sudden burst of intense electrical activity in the brain. This causes a temporary disruption to the way the brain usually works.

There are different types of epileptic seizure.

What happens to you during a seizure depends on what part of the brain is affected. You may have strange sensations or movements you cannot control. Or you may go stiff, fall to the floor and shake. Some people have seizures in their sleep.

You may be aware that you are having a seizure and remember it afterwards, or you may not.

Epileptic seizures are different from febrile seizures. These can happen in children when they have a high temperature.

Epileptic seizures are also different from functional (dissociative) seizures. These types of seizures look and feel like epileptic seizures. But they can happen for psychological reasons, such as stress or traumatic events.

Epilepsy is one of the most common serious brain conditions in the world. It affects around 630,000 people in the UK. This means that almost 1 in 100 people in the UK have epilepsy.

Around 87 people are diagnosed with epilepsy in the UK every day.

There are some things that can cause epilepsy.

• If a person’s brain did not develop properly before they were born
• Stroke
• Brain injury
• Brain tumour
• Infections, such as tuberculosis, cerebral malaria, and HIV
• Changes in a person’s genes. Some genes are linked to epilepsy types, such as Dravet syndrome and Lennox-Gastaut syndrome.

A cause means that these health problems can directly lead to epilepsy. But it does not mean that it will.

For example, a stroke can damage the brain, which can cause epilepsy. But it does not mean that if you have a stroke you will definitely develop epilepsy.

But in around half of all people with epilepsy, doctors don’t know the cause.

There are also things that increase the chance of developing epilepsy. But it does not guarantee it. You can have a risk factor and never develop the condition.

Things that can increase the risk of developing epilepsy include:

• Being born very premature (early), which can affect brain development
• Being born with a brain abnormality
• Having a brain injury, brain infection (like meningitis), brain tumour, or brain surgery
• Having severe febrile seizures as a child
• Having a family history of epilepsy
• Having certain genetic conditions that affect the skin and brain, such as tuberous sclerosis, neurofibromatosis, Sturge-Weber syndrome
• Neurodevelopmental conditions, such as ADHD, autism or learning disability
• Other medical conditions, including diabetes, high blood pressure, irregular heartbeat (atrial fibrillation), stroke, or dementia.

Seizure triggers are things that make seizures more likely in people with epilepsy. They’re not usually the same as things that cause, or increase your risk of developing epilepsy.

Most people with epilepsy can identify at least one or two things that trigger a seizure. This may include stress, tiredness, recreational drugs or alcohol.

There is no single test that can confirm an epilepsy diagnosis. Your doctor will need to assess your symptoms thoroughly. You may also have several medical tests.

Epilepsy should be diagnosed by a neurologist. This is an expert in conditions that affects the brain and nerves. Neurologists who specialise in epilepsy are also sometimes called epileptologists.

Call 999 if someone is having a suspected seizure for the first time.

You should see your GP as soon as possible if you, or someone you care for, has had a suspected seizure and you did not go to the hospital at the time.

How long an epilepsy diagnosis will take depends on a few things. This includes where you live and what your symptoms are.

Diagnosing epilepsy can take time. There are things you can do to stay safe while you are waiting.

Find out more about diagnosing epilepsy.

Epilepsy usually cannot be completely cured. But many people stop having seizures with the right treatment.

A small number of people outgrow epilepsy. This means the seizures stop without ongoing treatment. This sometimes happens with some types of epilepsy that start in childhood, including:

• Childhood absence epilepsy (CAE)
• Self-limited epilepsy with centrotemporal spikes

The main treatment for epilepsy is medicine. These are sometimes called anti-seizure medications (ASMs) or anti-epileptic drugs (AEDs).

Medicine does not cure epilepsy. But it may help stop or reduce the number of seizures you have, or make them less severe.

About half of people with epilepsy have their seizures stop with the first medicine they try. But some people need to try a few medicines before they find one that works well for them. And some people need to take 2 or more epilepsy medicines together.

Around 3 in 10 people with epilepsy have seizures that do not respond well to epilepsy medicine. They continue to have seizures even though they have tried 2 or more different medicines. Some people may be diagnosed with drug-resistant epilepsy.

There are other treatment options available if epilepsy medicine does not work. This includes:

• Ketogenic diet
• Epilepsy surgery
• Vagus Nerve Stimulation (VNS)
• EASEE ® (for people who have focal seizures)

You may not think of yourself as disabled. But you may be protected against disability discrimination under The Equality Act 2010 if you have epilepsy. Find out more about epilepsy and disability rights.

Epilepsy affects everyone in different ways. Watch our video to see Paul, Lauren, Patience, Harry, Rosie, Lucy and Helen talk about the impact epilepsy has on their lives.

Living with epilepsy is not only about seizures. How the condition affects you will depend on:

• Your type of seizures
• How well controlled they are
• Your overall health and your lifestyle

Many people with epilepsy live healthy lives, but there are some risks to be aware of.

Sleep issues

Sleep and epilepsy can affect each other. Seizures can cause overwhelming tiredness and epilepsy medicines can also make sleep worse.

Sleep disorders are also more common in people with epilepsy. This includes sleep apnoea and insomnia. Find out more about epilepsy and sleep issues.

Thinking and memory problems

Some people with epilepsy can have problems with memory. This may be because of seizures, side effects of epilepsy medicines or stress.

Mental health problems

Living with a long-term condition like epilepsy can make things hard sometimes. It’s important to look after your mental health as well as your physical health. Find out more about epilepsy and your wellbeing.

Status epilepticus and SUDEP

SUDEP is the sudden unexpected death of someone with epilepsy who was previously well and where the post-mortem cannot find another cause of death.

SUDEP is rare, affecting around 1 in every 1,000 people with epilepsy each year. But it is important to understand the risks, so you can minimise them where possible.

Find out about SUDEP and epilepsy-related deaths.

Bone health

Long-term treatment with some epilepsy medicines can increase the risk of developing weak bones. This is known as osteoporosis. There are things you can do to keep your bones healthy. Find out more about bone health and epilepsy.

Epilepsy and hormones

Epilepsy can affect your periods and perimenopause and menopause.

Most people with epilepsy have healthy pregnancies and healthy babies. But there are some known possible complications if you have epilepsy.

It’s important to get medical advice before you start a family if you are male or female. This is known as pre-conception counselling.

How you can help someone having a seizure will depend on what type of seizures they have. Visit first aid for seizures for more information.

Take our short online course to find out what to do when someone has a seizure.

Whether you are a parent, employer, carer or work in a school, we are here for you.

You can contact the Epilepsy Action helpline by phone, email or having a live chat.

“If you or someone you love has been given a diagnosis of epilepsy, it’s OK to feel overwhelmed and frightened. Epilepsy Action was there for us as a family when we were sent on our way from consultations with specialists and GPs. You feel less alone hearing the stories and experience others via Epilepsy Action.”

Parents

If your child has epilepsy, our information and support for parents is for you. It includes advice on epilepsy in school, virtual support groups for parents and an online course.

We also have information for parents with epilepsy to help you explain it to children.

Carers of people with epilepsy and a learning disability

We have information about caring for someone with epilepsy and a learning disability.

For care and support staff, we have online courses that give the skills you need to work effectively with people with the condition.

Employers

We have online training courses for managers and HR professionals.

School staff

Find out more about our free online training for schools.

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