What is Epilepsy?

London, October 17, 2009 (Pal Telegraph) - Epilepsy is a serious condition, but drug treatments work well. With drug treatment, most people get fewer seizures. For some people, drugs stop their seizures altogether. We've brought together the best research about epilepsy and weighed up the evidence about how to treat it. You can use our information to talk to your doctor and decide which treatments are best for you or your child.
Other conditions

* Absence seizures in children,
* Bell's palsy,
* Dementia,
* Essential tremor,
* Headache, chronic tension type,
* Migraine in adults,
* Migraine in children,
* Multiple sclerosis,
* Parkinson's disease,
* Stroke, emergency care,
* Trigeminal neuralgia,

If you or your child has epilepsy, the normal electrical activity in the brain gets disturbed from time to time. This leads to seizures (also called fits).

During a seizure, you may feel strange and act oddly. Your muscles may go limp or stiff, and you may shake, twitch or black out. Seizures tend to be over quickly. Most people are back to normal within a few minutes.

Although epilepsy is a serious condition, it should not stop you or your child from leading a healthy, active life. Drug treatments work well. Most people stop having seizures, or at least have them less often, once they get the right drug treatment.
Key points for people with epilepsy

* If you have epilepsy, you get seizures. These seizures may come out of the blue or you may get a warning sign, such as a strange feeling or smell.
* What happens to you during a seizure depends on what part of your brain it affects. Not everyone blacks out or falls down.
* If you or your child has had just one seizure, epilepsy may not be the cause. Doctors usually wait to see if another seizure happens before starting treatment.
* Drug treatment can reduce the number of seizures, make them less severe or stop them altogether. But it can have unpleasant side effects.
* If drug treatment doesn't help, surgery to remove part of your brain where the seizures start may be another option.
* Most people with epilepsy lead a full, healthy and active life.

How the brain works

To understand what happens in epilepsy, it's useful to know how your brain normally works.

Your brain controls everything you do.

* Your brain allows you to think, to speak, to move your body and to remember things.
* It's also responsible for the things your body does automatically, such as breathing and digesting food.

Your brain is made up of billions of nerve cells that share information with each other. These cells are organised in chains. They are not actually joined together, but they sit close to each other with a space between them called a synapse.

Groups of nerve cells have specific jobs to do. For example:

* Some are involved in thinking, learning, remembering and planning
* Others deal with seeing or hearing
* Others manage the millions of jobs that keep your body working.

* Tiny electrical signals travel from one nerve cell to the next with the help of chemicals called neurotransmitters.
* To reach nerve cells throughout your body, these electrical signals travel from your brain to your spinal cord. This is a tube of nerves that runs down your back from your brain. It sits inside the bones that make up your spine.
* Once an electrical signal reaches your spinal cord, it can then travel along nerves to your arms, legs and elsewhere in your body.

What happens to your brain in epilepsy

In epilepsy, nerve cells in your brain tend to become overexcited.

* The nerve cells produce electrical signals faster than usual and in bursts.
* The electrical signals are stronger and more disorganised than usual.
* The result is a seizure.

A seizure affects how your brain does its many jobs. This is why a person having a seizure feels strange and acts in odd ways. Seizures can affect nerve cells in one particular part of your brain (these are called partial seizures). Or they can affect nerve cells all over your brain (these are called generalised seizures). See What are the symptoms of epilepsy? to learn more about seizures.

Sometimes, only a small group of nerve cells becomes overexcited. When this happens, the seizure may start off affecting only one part of your body. Your hand may shake or feel stiff, for example. But then other cells nearby may join in and start firing off signals. This makes your symptoms worse. For example, a whole arm or one side of your body may shake or feel numb.

Because different parts of the brain do different jobs, the symptoms you or your child gets depend on where in the brain the burst of electrical activity happens. To read more, see The parts of the brain and what they do.
Why do seizures happen?

Unfortunately, we know very little about why seizures happen or how they start and stop. But doctors think that epilepsy may be due to a problem with the links between nerve cells, the balance of chemicals in your brain, or a combination of both those things.[1]

We know that two brain chemicals (neurotransmitters) are important for slowing down and speeding up electrical signals in the brain:

* A chemical called glutamate helps to keep electrical signals moving
* And a chemical called GABA (gamma-aminobutyric acid) helps to stop electrical signals passing from one brain cell to the next.

Doctors think that if you have too much glutamate in your brain, it could lead to too many electrical signals firing at once. And if you have too little GABA, then electrical signals can fire out of control. Some drugs help to control seizures by affecting the levels of these chemicals in the brain.

Your doctor may not be able to tell you why you or your child has epilepsy. Around 7 in 10 people with epilepsy never find out the cause. If the cause isn't clear, the condition could be because of a problem with the genes that control how the brain works.[2]

But for some people, an illness, infection, injury or problem in the way their brain developed has caused their epilepsy.[3] All these things can change the structure of the brain, upsetting the way electrical signals work and leading to seizures.

If you get epilepsy as an adult, you're more likely to find out what caused the condition than if you get it as a child.

Some things increase your chances of getting epilepsy, such as having a learning disability or getting older. Doctors call these risk factors. To learn more, see Who's at risk?
References

1. Lowenstein DH. Seizures and epilepsy. In: Braunwald E, Hauser SL, Fauci AS, et al. Harrison's principles of internal medicine. 15th edition. McGraw-Hill, New York, U.S.A.; 2001.
2. Hauser WA, Annegers JF. Risk factors for epilepsy. Epilepsy Research. Supplement. 1991; 4: 45-52.
3. National Institute of Neurological Disorders and Stroke. Seizures and epilepsy: hope through research. May 2004. Available at http://www.ninds.nih.gov/disorders/epilepsy/detail_epilepsy.htm (accessed on 15 December 2006).

Glossary

Your genes are the parts of your cells that contain instructions for how your body works. Genes are found on chromosomes, structures that sit in the nucleus at the middle of each of your cells. You have 23 pairs of chromosomes in your normal cells, each of which has thousands of genes. You get one set of chromosomes, and all of the genes that are on them, from each of your parents.
learning disability

People with a learning disability have trouble with the basic processes of learning. They may have problems in the way they think and find reading or writing very difficult.

Other conditions

Epilepsy - What are the symptoms?

The symptoms of epilepsy are seizures. A seizure happens when the normal electrical activity in your brain goes wrong.

There are lots of different types of seizures. They can look and feel very different, depending on where in the brain they start and how far and how quickly they spread.[1] [2] For example:

* You may get a strange feeling, as though you're out of touch with your surroundings
* Your muscles may feel stiff or limp
* Your arms may jerk suddenly
* You may twitch or tremble
* You may black out and fall to the ground.

Some people get a warning sign, such as a strange smell or feeling, before their seizure starts. These are called auras. Other people get no warning and their seizure comes on suddenly.

Sometimes, seizures are set off by things such as lack of sleep or flashing lights. Doctors call these things triggers.[3] (To learn more, see Things that trigger seizures.)

Once a seizure ends, some people know what happened to them. But you may not.

The length of seizures can vary. They can last for a few seconds or several minutes.

Most people don't get symptoms between seizures. But if their epilepsy is caused by a problem in the brain (such as a tumour, infection or an injury), then this may lead to other problems besides the seizures. Drug treatments for epilepsy may also cause headaches, rashes and other side effects.
Types of seizures

It's important to work out what type of seizure you or your child is having. This is because:

* Some treatments work best for certain types of seizures
* Your seizure pattern (the type of seizure you get and how often they happen) may suggest what's causing the epilepsy.

Seizures are usually divided into two main groups according to where they start in the brain and what happens to you during them:[1]

* Partial seizures (doctors sometimes call these focal seizures)
* Generalised seizures.

But not all seizures can be grouped under these headings, especially those in babies. Doctors call these unclassified seizures.
Partial (focal) seizures: how they affect you

In a partial (focal) seizure, only part of the brain is affected. Symptoms depend on what that part of the brain does. (To learn more, see The parts of the brain and what they do.)

Partial seizures can be divided into simple partial seizures or complex partial seizures.[1] 'Simple' means the person doesn't black out. 'Complex' means the person passes out or becomes less aware of his or her surroundings. Epilepsy that causes partial seizures is sometimes called focal epilepsy and partial seizures are sometimes called focal seizures. This is because they start from a particular focus (which means area) of the brain.

Here's a summary of the main symptoms. Click on the links below to read more about how each type of seizure looks and feels.

* Simple partial (focal) seizures: During this type of seizure, you remain aware of what's going on. The muscles in your arms, legs and face may become stiff, and your limbs may twitch on one side of your body. You may have unusual sensations, such as strange smells, distorted vision, a rising feeling in your stomach, changes in emotion, or a feeling of fear or déjà vu.[1]
* Complex partial (focal) seizures: With this type of seizure, you often have a warning sign (an aura) before the seizure starts, and you may become less aware of your surroundings. You may not answer when called or you may pass out. Some people start fidgeting, walking around or doing something over and over again, like chewing or smacking their lips (doctors call these automatisms).[1]

Sometimes partial seizures spread throughout the brain. If this happens, you may have a generalised seizure (often a tonic-clonic seizure).
Generalised seizures: how they affect you

These affect your whole brain. During most of these seizures, the person passes out (loses consciousness). These are the main types of generalised seizure.[1] [2] Click on the links below to read more about how each type looks and feels.

* Tonic-clonic seizures: A tonic-clonic seizure causes a mixture of symptoms, including stiffening of the body and jerking of the arms and legs. The person blacks out, and may bite their tongue or wet themselves.
* Absence seizures: The person appears to be staring blankly into space, unaware of his or her surroundings. Muscles may jerk or twitch, and the eyes may flutter. These seizures pass very quickly. They usually last only three seconds to 10 seconds.
* Myoclonic seizures: The upper body, arms or legs jerk or twitch as if they are being shocked. This may happen once or more than once. People tend not to black out during these seizures.
* Atonic seizures: The muscles suddenly relax, which makes the person fall down without warning or drop his or her head forward. The person blacks out.

Sometimes doctors say a person has an epilepsy syndrome. An epilepsy syndrome is when you have a number of particular symptoms at the same time. An epilepsy syndrome may include more than one type of seizure. There are many epilepsy syndromes, but some are very rare. Children are more likely than adults to have an epilepsy syndrome.[4] To learn more, see Epilepsy syndromes.

Knowing which type of epilepsy syndrome you or your child has can help your doctor decide on the best treatment. It can also help work out if the epilepsy will change in the future and whether it can be passed on from parent to child.
References

1. International League Against Epilepsy. Proposal for revised clinical and electroencephalographic classification of epileptic seizures. Epilepsia. 1981; 22: 489-501.
2. Mosewich RK, So EL. A clinical approach to the classification of seizures and epileptic syndromes. Mayo Clinic Proceedings. 1996; 71: 405-414.
3. Browne TR, Holmes GL. Epilepsy. New England Journal of Medicine. 2001; 344: 1145-1151.
4. National Institute for Health and Clinical Excellence. Newer drugs for epilepsy in children. April 2004. NICE technology appraisal 79. Available at http://www.nice.org.uk/ta079 (accessed on 15 December 2006).

Glossary

brain tumour
A brain tumour is when a lump of cells that are growing out of control (a tumour) develops in your brain. Tumours can be malignant (cancerous), which means the cells in the tumour invade and destroy nearby cells and can spread to other parts of your body. Or tumours can be benign (non-cancerous), which means the cells in the tumour don't invade other cells or travel to other parts of your body. A tumour in your brain can cause problems by pushing on parts of your brain and affecting how they work.

Other conditions

Epilepsy - How common is it?

Epilepsy is one of the most common brain disorders in the UK. Anyone can get epilepsy at any age.

In the UK, up to 1 in 100 people have epilepsy.[1] Up to 5 in 100 people will have a seizure at some point in their lives.[1] But, many seizures are not caused by epilepsy.

Although epilepsy can begin at any age, it usually starts in young children or older people.[2]
References

1. National Institute for Clinical Excellence. The epilepsies: the diagnosis and management of the epilepsies in adults and children in primary and secondary care. October 2004. Clinical guideline 20. Available at http://www.nice.org.uk/cg20 (accessed on 8 January 2008).
2. Sander JW, O'Donoghue MF. The epidemiology of epilepsy revisited. Current Opinion in Neurology. 2003; 16: 165-170.

Other conditions