What is Epilepsy?

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What is Epilepsy?


Epilepsy is a central nervous system disorder (neurological disorder) in which the nerve cell activity in your brain becomes disrupted, causing a seizures or periods of unusual behavior,  sensations and sometimes loss of consciousness.

Seizure symptoms can vary widely. Some people with epilepsy simply stare blankly for a few seconds during a seizure, while others repeatedly twitch their arms or legs.

About 1 in 26 people in the United States will develop a seizure disorder. Nearly 10 percent of individuals may have a single unprovoked seizure. However, a single seizure doesn’t mean you have epilepsy. At least two unprovoked seizures are generally required for an epilepsy diagnosis.

Even mild seizures may require treatment because they can be dangerous during activities such as driving or swimming. Treatment with medications or sometimes surgery can control seizures for about 80 percent of people with epilepsy. Some children with epilepsy may also outgrow their condition with age.

Source: The Mayo Clinic – https://www.mayoclinic.org/diseases-conditions/epilepsy/home/ovc-20117206 – Reviewed Nov. 06, 2015

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What causes epilepsy and who gets it?


Epilepsy has no identifiable cause in about half of those with the condition. In the other, the condition may be traced to various factors.

  • Genetic influence – Some types of epilepsy, which are categorized by the type of seizure you experience or part of the brain that is affected, run in families. In these cases, it’s likely that there’s a genetic influence. Researchers have linked some types of epilepsy to specific   genes, though it’s estimated that up to 500 genes could be tied to the condition. For most people, genes are only part of the cause of epilepsy. Certain genes may make a person more sensitive to environmental conditions that trigger seizures.
  • Head trauma – Head trauma as a result of a car accident or other traumatic injury can cause epilepsy.
  • Brain conditions – Brain conditions that cause damage to the brain, such as brain tumors or strokes, can cause epilepsy. Stroke is a leading cause of epilepsy in adults older than age 35.
  • Infectious diseases – Infectious diseases, such as meningitis, AIDS and viral encephalitis, can cause epilepsy.
  • Prenatal injury – Before birth, babies are sensitive to brain damage that could be caused by several factors, such as an infection in the mother, poor nutrition or oxygen deficiencies. This brain damage can result in epilepsy or cerebral palsy.
  • Developmental disorders – Epilepsy can sometimes be associated with developmental disorders, such as autism and neurofibromatosis.

Source: The Mayo Clinic: https://www.mayoclinic.org/diseases-conditions/epilepsy/symptoms-causes/dxc-20117207– Reviewed Nov. 06, 2015

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What is a seizure?


The brain controls the body’s actions, sensations and emotions through nerve cells that carry messages between the brain and the body. These messages are transmitted through regular electric impulses. A seizure occurs when sudden bursts of electrical activity in the brain disrupt this pattern. The kind of seizure and the parts of the body affected by it relates to the part of the brain in which the irregular electrical activity occurred. Seizures can involve loss of consciousness, a range of unusual movements, odd feelings and sensations, or changed behaviour.

Source: Epifile: An Epilepsy Management Manual. Epilepsy Australia Ltd. Updated June 2013

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Seizure Types


Seizures fall into two different categories: focal and generalised seizure.  The difference between these two types is whether the whole or part of the brain is involved.

Focal Seizuresfocal

When seizures appear to result from abnormal activity in just one area of your brain, they’re called focal (partial) seizures. These seizures fall into two categories.

  • Focal seizures without loss of consciousness (simple partial seizures) – These seizures don’t cause a loss of consciousness. They may alter emotions or change the way things look, smell, feel, taste or sound. They may also result in involuntary jerking of a body part, such as an arm or leg, and spontaneous sensory symptoms such as tingling, dizziness and flashing lights.
  • Focal dyscognitive seizures (complex partial seizures) – These seizures involve a change or loss of consciousness or awareness. During a complex partial seizure, you may stare into space and not respond normally to your environment or perform repetitive movements, such as hand rubbing, chewing, swallowing or walking in circles.

Symptoms of focal seizures may be confused with other neurological disorders, such as migraine, narcolepsy or mental illness. A thorough examination and testing are needed to distinguish epilepsy from other disorders.

Source: The Mayo Clinic: https://www.mayoclinic.org/diseases-conditions/epilepsy/symptoms-causes/dxc-20117207– Reviewed Nov. 06, 2015

Generalised Seizuresgeneralised

Generalised seizures involve the whole brain and therefore the whole body. There are many different types of generalised seizures – some convulsive and others non convulsive.

Absent Seizures – These brief, non-convulsive events involve the whole brain and usually occur in children.  With this type of seizure, the person’s awareness and responsiveness are impaired. They simply stare and their eyes might roll back or their eyelids flutter.

It can be difficult to tell the difference between absence seizures and daydreaming. However, absence seizures start suddenly, cannot be interrupted, last a few seconds, and then stop suddenly and the person resumes what they were doing. Although these seizures last less than 10 seconds, they can occur many times daily, and thus be very disruptive to learning.

Myoclonic Seizures – Myoclonic seizures are brief, shock-like jerks of a muscle or a group of muscles, usually lasting no more than a second or two, which at times can result in a fall. There can be just one, but sometimes many will occur within a short time.

Atonic seizures cause a sudden loss or decrease of normal muscle tone and the person often falls to the ground. Seizures usually last less than 15 seconds. Often called ‘drop attacks’, these seizures can cause head or facial injury. Wearing protective head wear may avoid injury

Atonic Seizures – Tonic seizures greatly increase normal muscle tone and the body, arms, or legs make sudden stiffening movements. These seizures most often occur in clusters during sleep, although they can occur when the person is awake.  If the person is standing they will fall quite heavily, often injuring their head. Protective headwear may avoid injury. Seizures usually last less than 20 seconds.

Tonic-Clonic Seizures – During a tonic-clonic seizure a person’s body stiffens, air being forced past the vocal cords causes a cry or groan, and they fall to the ground (the tonic phase). Their limbs then begin to jerk in strong, symmetrical, rhythmic movements (the clonic phase). The person may dribble from the mouth, go blue or red in the face, or lose control of their bladder and/or bowel as the body relaxes. As consciousness returns, the person may be confused, drowsy, agitated or depressed. They may have a headache and want to sleep. This drowsiness can last for a number of hours.

Although this type of seizure can be frightening to watch, the seizure itself is unlikely to seriously harm the person having the seizure. They may, however, vomit or bite their tongue and can sometimes injure themselves if they hit nearby objects as they fall or convulse.

Tonic-clonic seizures generally last 1 to 3 minutes.  If the active movements of the seizure last more than 5 minutes it is advisable to call an ambulance. Prolonged seizures, or a series of seizures without a normal break in between, indicate a dangerous condition called convulsive status epilepticus and demands emergency treatment.

Source: Epifile: An Epilepsy Management Manual. Epilepsy Australia Ltd. Updated June 2013

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Why do seizures occur?


Seizures are most common in young children and the elderly, but they can occur for the first time at any age.

Sometimes it is easy to see the cause of a seizure. For example, a seizure may occur at the time of a bad head injury or brain infection.  Seizures are occasionally caused by high fevers (especially in children), the use of certain drugs or excessive intake of alcohol. In other cases an injury or infection of the brain that happened a long time ago can cause a seizure.

Seizures may also be brought on by significant stress or lack of sleep. These ‘triggers’ alone, however, do not explain why a seizure has occurred. After all, not everyone who is stressed or sleep deprived will have a seizure. Tests are still needed to ensure that no other cause can be found. It appears that certain people are simply more prone to having seizures than others. This is, at times, described as having a ‘low-seizure threshold’ and may be due to an individual’s genetic makeup.

In many cases, despite thorough medical investigation, the cause of a seizure cannot be determined.

Source: Epifile: An Epilepsy Management Manual. Epilepsy Australia Ltd. Updated June 2013

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Seizure triggers


Some people, although not all, find that certain factors induce seizures. You may not become aware of your trigger factors unless you keep a seizure diary for a period of time. The following list of trigger factors is a guide but it is by no means an exhaustive list.

Alcohol – Epilepsy shouldn’t stop you from having the occasional beer or two or a glass of wine with dinner. Most people with epilepsy can drink a moderate amount of alcohol. Moderate drinking means having 2 standard drinks a day.

A standard drink is equal to:

  • One small glass of wine (100ml)
  • One middy of full strength beer (285ml)
  • One nip of spirits (30ml)

Be aware of the quantity of alcohol you drink and don’t let anyone persuade you to drink more. Alcohol and antiepileptic medications interact in specific ways. AEDs can make you more sensitive to the sedating effects of alcohol while alcohol reduces the effectiveness of AEDs making seizures more likely. Excessive drinking can result in poor seizure control due to late nights, missed meals, or forgotten doses, while ‘hangover’ seizures are likely to occur as the alcohol level in the blood falls.

Excessive drinking can result in:

  • Poor seizure control due to late nights
  • Missed meals
  • Forgotten doses
  • Hangover seizures as the alcohol level in the blood falls.

However some people find that even small amounts of alcohol can trigger seizures. Ask your doctor about the effects of drinking alcohol with the medication you have been prescribed.

Alcohol and epilepsy The Epilepsy Report, Issue 2, 2008

Diet – Coffee, tea and drinks with cola contain caffeine. In some people caffeine can trigger seizures while others are susceptible to having seizures if they miss meals and have a low blood sugar level. Regular meals and eating immediately after getting out of bed in the morning will protect you against large swings in blood sugar levels.

Infections and illness – Children are particularly likely to have more seizures when they develop infections such as tonsillitis and earache. This is possibly due to high temperature and usually eases within a few days. Allergies may provoke seizures in some people with epilepsy. Diarrhoea and vomiting can trigger seizures because they can prevent your body from absorbing your antiepileptic medication. Ask your doctor what you should do if this occurs.

Lack of sleep – This is a common trigger factor. Everyone differs in the amount of sleep they need, however avoid wild fluctuations in the time you go to bed and make sure you get enough sleep to feel rested.

Menstruation – Some women find that they have more seizures just before or during their menstrual period. This may be caused by a combination of factors such as increased fluid retention, alteration in hormonal levels and alteration in the blood levels of antiepileptic medications. A significant increase in seizure activity at this time is known as catamenial epilepsy. If you notice this happening, discuss it with your doctor. By altering your dose of antiepileptic medication or introducing another medication your doctor may be able to control or ease the problem.

Missed medication – Some people are particularly sensitive to increased seizures when they miss a dose of their antiepileptic medication. The longer the break between doses, the lower your blood levels will go and the greater your chance of having a seizure. If you take your medication erratically or you suddenly stop taking all medication, you may trigger a severe and prolonged seizure or a cluster of seizures that will require hospitalization.

Other drugs – Withdrawal from sedative and hypnotic drugs including minor tranquillisers, sleeping pills and illegal drugs can be a problem, as can combining these drugs with antiepileptic medication. It is important to tell your doctor about all the medications you take. And this includes telling him or her about any over the counter herbal or vitamin supplements that you are taking or planning to take.

Other possible triggers

There are other possible triggers with some unique to certain people. For example some unusual stimuli known to trigger seizures include the colour yellow, the smell of glue and sounds such as the telephone ringing or a siren.

Photosensitivity
Photosensitive epilepsy is rare affecting only a small number of people with epilepsy. With photosensitive epilepsy seizures are triggered by sensory stimuli such as flickering sunlight, strobe lights and flickering television. Simple preventative measures can be taken to decrease seizures triggered this way such as wearing wrap-around sunglasses to reduce glare and covering one eye to reduce the effects of flickering or flashing light. Most computer monitors do not present a problem, however if you are sensitive to screen flicker, try using a non-interlaced monitor and take regular breaks.

Epilepsy and light The Epilepsy Report, Issue 2, 2008

Severe changes in temperature
In some people seizures may be triggered when the weather becomes very warm or rooms are overheated.

Stress
Stress is a normal part of life. In fact we need a certain amount to motivate ourselves and to stay healthy. Extreme stress, however, may lower your seizure threshold and trigger seizures. It is important to learn to recognise the signs and symptoms of harmful levels of stress and to employ strategies that you find helpful in reducing it. Relaxation techniques such as yoga, breathing exercises or aerobic exercise might be options worth trying.

Source: Epifile: An Epilepsy Management Manual. Epilepsy Australia Ltd. Updated June 2013

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Diagnosing Epilepsy


There are many medical reasons why people lose consciousness, experience periods of time when they are ‘not quite with it’ or have unusual sensations. These include panic attacks, migraine, faints (sometimes called ‘syncope’), seizures, stroke and heart disease. A definite diagnosis is important, but because the person often has little or no memory of the event it can take time to come to the right answer.

The doctor will begin by taking a thorough medical history and examining the patient. Eyewitness accounts can assist greatly with the diagnosis, so it is useful for a friend or family member who saw the event to accompany the patient to the first appointment.

If a stranger witnessed the event, a written description or a phone number for the doctor to call can be helpful. Tests may be arranged, and these will vary depending upon the doctor’s initial assessment. They may include blood tests, an EEG [electroencephalogram], a CT scan [computerized tomography] or an MRI [magnetic resonance imaging].

Sometimes it is very clear why a person has experienced a collapse or ‘blackout’. But occasionally, even after all the appropriate tests and a thorough examination of the person’s medical history, it is still not possible to make a definite diagnosis. This can be frustrating.

Often it is a matter of simply waiting for a definite answer. More events may allow a clear diagnosis, or a further test may provide an answer. It is better to be a little uncertain rather than to jump to conclusions and make a wrong diagnosis.

Source: Epifile: An Epilepsy Management Manual. Epilepsy Australia Ltd. Updated June 2013

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All information contained within this page is to the best of our knowledge accurate and useful. It is not meant to substitute direct contact with your local health professionals.

For more information please see Epilepsy Australia