Epilepsy is a general term that refers to a tendency to have recurrent seizures. There are various types of seizures. People with diagnosed epilepsy often have only one type of seizure, although some experience more than one type. The term "epilepsy" can be used interchangeably with "seizure disorder." Epilepsy is not contagious and poses no risk to others.

Causes

Epilepsy is difficult to diagnose as each person may have their own unique internal triggers causing their seizures. What doctors do know are that people with certain conditions are more prone towards having epilepsy. Most often, these triggers such as strokes, poisoning and other types of brain injuries can be controlled once they are discovered. Regardless of its cause, epilepsy is not contagious.

Types of Seizures

There are two ways that seizures come into being, partial which means an electrical disturbance goes from one part of the brain to the other and generalized in which the entire brain is affected all at once. Regardless of how the seizure came into being, the person suffering from the seizure may feel confused or sleepy for an extended period of time. Most seizures last only a few seconds but can sometimes extend over several minutes.

Seizures can be triggered by over-stimulation of the brain, flashing or bright lights, lack of sleep or even certain types of medication. If you think you have suffered from a seizure, you should visit a doctor to get diagnosed right away.

Seizures are episodes during which the electrical system within the brain fires abnormally. The term “epilepsy” refers to any disorder characterized by recurrent seizures. During a seizure, you may lose consciousness, stare into space, have convulsions (abnormal jerking of the muscles), or experience abnormalities of sensation or emotion. Epilepsy is a term used to describe a condition in which you have recurrent seizures. Because seizures can be an indication of another, underlying medical problem, such as brain tumor, it is important to seek medical attention if you have even one seizure.

Seizure disorders may be classified by the part of the brain they affect or the kinds of symptoms they cause. The main categories are generalized or partial seizures.

Generalized seizure disorders are caused by more widespread abnormalities throughout the brain. Generalized seizure disorders include:

• Tonic-clonic or Grand Mal Seizures–classic convulsions, in which you lose consciousness and muscles throughout the body jerk uncontrollably

• Absence or Petit Mal Seizures–seizures which manifest by staring, eye blinking, or eye rolling

Seizures that accompany fevers in young children are often of this type. Children will generally outgrow the tendency to have seizures with fevers. The tendency to have seizures with fevers runs in families. However, even with a history of seizures with fevers, medical attention should be sought immediately because of the possibility that the seizure may be related to a more serious medical condition such as encephalitis or meningitis.

Partial seizure disorders are caused by more localized abnormalities within certain areas of the brain. Partial seizure disorders include:

• Complex Partial or Temporal Lobe Seizures–during this type of seizure, you will briefly lose contact with reality, stop purposeful activity, and begin a series of automatic gestures, such as lip smacking, hand wringing, picking at clothing, etc. Not everyone develops automatic gestures during these seizures; sometimes it simply appears as a brief moment of confusion or loss of attentiveness. Occasionally this type of seizure is accompanied by the perception of unusual sights, sounds, or smells.

• Simple Partial Seizures–in this type of seizure, you don’t lose contact with reality or consciousness, but a single area of your body moves uncontrollably, such as a leg or arm shaking. You may experience an odd sensation, such as the perception of an odor, sound, or taste, or an emotional response unrelated to the environment.

Seizure disorders are potentially serious conditions that require care from your doctor. If you suspect you have a seizure disorder, contact your doctor immediately.

Causes

Epilepsy can arise as a result of many different conditions that affect the brain. Examples of these conditions include stroke (resulting from a blockage of the blood supply to parts of the brain), complications during childbirth, infections (such as meningitis, encephalitis, cysticercosis, or brain abscess), head trauma, and certain genetic disorders. Often, definite causes of epilepsy cannot be identified; in these instances, the cause may be labeled "idiopathic" or "cryptogenic." Hereditary factors may contribute to the development of idiopathic epilepsy. Seizures occur when the electrical signals that pass between nerve cells within the brain become abnormal. This may occur for no known reason, or it may follow an injury to the brain, such as occurs from:

• Abnormalities of the brain structure (congenital brain abnormalities)

• Birth injuries which deprive the brain of oxygen

• Traumatic brain injury (concussions, skull fractures, oxygen deprivation due to near-drowning, etc.)

• Brain infection (encephalitis or meningitis, brain abscess)

• Brain tumor

• Sudden spike in fever in a baby or very young child (febrile seizure)

• Medications such as penicillins, theophylline, lidocaine, meperidine, amitriptyline, imipramine, doxepin, fluoxetine, haloperidol, chlorpromazine, ephedrine, terbutaline, methotrexate, asparaginase, cyclosporine

• Street drugs such as cocaine, crack, and amphetamines

• Withdrawal from certain medications, street drugs, or alcohol

• Drug overdose

• Chemical abnormalities (decreased or excess blood sodium or glucose, low blood calcium)

• Liver or kidney failure

• Severe, untreated high blood pressure

• Chronic diseases such as systemic lupus erythematosus, polyareteritis nodosa, porphyria, sickle cell disease, Whipple’s disease

• Syphilis

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

The following factors increase your chance of developing a seizure disorder. If you have any of these risk factors, tell your doctor:

• Previous brain injury

• Previous brain infection

• Brain tumor

• History of stroke

• High fever (especially common in babies or young children; called “febrile seizure”)

• Use of certain medications or recreational drugs

• Stopping the use of medications, recreational drugs, or alcohol

• Drug overdose

• Exposure to toxins such as arsenic, lead, or carbon monoxide

• Alzheimer’s disease

• Eclampsia (toxemia) during pregnancy

If you already have a seizure disorder, the following factors can increase your chance of having a seizure:

• Sleep deprivation

• Hormonal changes (such as those that occur at points during the menstrual cycle)

• Stress

• Flashing lights, especially strobe lights

• Use of certain medications

• Missing doses of antiepileptic medications

Symptoms

There are many kinds of seizure disorders, with a variety of symptoms. Possible symptoms include:

• Aura–a sensation prior to the start of seizure that may alert you to the coming seizure. The aura involve the perception of an odd smell or sound, spots appearing in front of the eyes, or unusual stomach or head sensations.

• Staring

• Loss of consciousness

• Repeated jerking of a single limb

• Generalized convulsion, with uncontrollable jerking of muscles throughout the body

• Hand rubbing

• Lip smacking

• Picking at clothing

• Perception of an odor, sound, or taste

• Inappropriate emotional outbursts, not related to what is going on in the environment

• Loss of bladder or bowel control

• Post-ictal state–a state of drowsiness and lack of responsiveness that commonly occurs after a grand mal seizure. This may last minutes or hours.

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical exam. You may need to see a neurologist, a specialist in conditions of the nervous system and brain.

Tests may include the following:

• Electroencephalogram (EEG)–a test of the electrical activity in the brain. This may be performed for a brief amount of time, or you may be given an ambulatory monitor to use for several days.

• CT scan or MRI scan to look for abnormalities in the brain, such as tumors, blood clots, malformed blood vessels, scarring, swelling, or excess fluid

• Lumbar puncture or spinal tap may be performed to screen for infection

Treatment

Prevention

Although there are no known ways to prevent every type of seizure disorder, you can take steps to prevent brain injuries which could lead to seizures:

• Always wear a helmet when biking, rollerblading, skateboarding, or riding on a scooter

• Wear protective headgear when playing sports like football or hockey

• Take care to dive in safe depths of water

• Always wear a seatbelt in all vehicles

• Avoid using street drugs

• Control high fevers in babies and young children

• Get prenatal care, and make sure to follow all recommendations regarding the treatment of high blood pressure during pregnancy

• Carefully treat all chronic illnesses

If you have a seizure disorder, you can take the following steps to try to decrease the possibility that you will have a seizure:

• Get sufficient sleep

• Avoid hyperventilating

• Avoid places where flashing or strobe lights are in use

• Wear a medical alert bracelet so that, if you have a seizure, people around you will understand what is happening and take appropriate steps to be helpful

• Consider keeping a seizure log, in which you record things that were happening around the time of a seizure to try to identify a seizure trigger

• Take your seizure medications very conscientiously according to your doctor’s prescription

Resources

Epilepsy Foundation
http://www.efa.org

National Institute of Neurological Disorders and Stroke
http://www.ninds.nih.gov

References:

Ferri FF, ed. Ferri’s Clinical Advisor: Instant Diagnosis and Treatment. Philadelphia, PA: Mosby Elsevier; 2004.

Goetz CG, ed. Textbook of clinical Neurology, 2nd ed. Philadelphia, PA: WB Saunders Company; 2006.

Goldman L, Ausiello D, eds. Cecil Textbook of Medicine, 22nd ed. Philadelphia, PA: WB Saunders Company; 2004.

CDC