Epilepsy is a disorder that results from the generation of electrical signals inside the brain, causing recurring seizures. Seizure symptoms vary. Some people with epilepsy simply stare blankly for a few seconds during a seizure, while others have full-fledged convulsions. About one in 100 people in the United States will experience an unprovoked seizure in their lifetime. However, a solitary seizure doesn't mean you have epilepsy. At least two unprovoked seizures are required for an epilepsy diagnosis. Even mild seizures may require treatment, because they can be dangerous during activities like driving or swimming. Treatment — which generally includes medications and sometimes surgery — usually eliminates or reduces the frequency and intensity of seizures. Many children with epilepsy even outgrow the condition with age.
Complications of Epilepsy
Having a seizure at certain times can lead to circumstances that are dangerous to yourself or others.
Falling. If you fall during a seizure, you can injure your head or break a bone.
Drowning. If you have epilepsy, you're more than 15 times more likely to drown while swimming or bathing than the rest of the population because of the possibility of having a seizure while in the water.
Car accidents. A seizure that causes either loss of awareness or control can be dangerous if you're driving a car or operating other equipment. Many states have driver's licensing restrictions related to your ability to control seizures and impose a minimum amount of time that you've been seizure-free — ranging from three months to two years — before you're allowed to drive.
Pregnancy complications. Seizures during pregnancy pose dangers to both mother and baby, and certain anti-epileptic medications increase the risk of birth defects. If you have epilepsy and you're considering becoming pregnant, talk to your doctor. Most women with epilepsy can become pregnant and have a healthy baby. You'll need to be carefully monitored throughout pregnancy, and medications may need to be adjusted. It's very important that you work with your doctor to plan your pregnancy.
Other life-threatening complications from epilepsy are uncommon, but do occur.
Status epilepticus. This condition occurs if you're in a state of continuous seizure activity lasting more than five minutes or you have frequent recurrent seizures without regaining consciousness in between them. People with status epilepticus have an increased risk of permanent brain damage and death.
Sudden unexplained death in epilepsy (SUDEP). People with poorly controlled epilepsy also have a small risk of sudden unexplained death. Overall, less than one in 1,000 people with epilepsy die from SUDEP, but it's more common among people whose seizures aren't controlled by treatment. The risk of SUDEP is particularly elevated when generalized tonic-clonic seizures are frequent.
Causes of Epilepsy
Epilepsy has no identifiable cause in about half of those who have the condition. In the other half, the condition may be traced to various factors.
Genetic influence. Some types of epilepsy, which are categorized by your type of seizure, run in families, making it 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 some, genes are only part of the cause, perhaps by making a person more susceptible to environmental conditions that trigger seizures.
Head trauma sustained during a car accident or other traumatic injury can cause epilepsy.
Medical disorders. Events like strokes or heart attacks that result in damage to the brain also can cause epilepsy. Stroke is responsible for up to one half of epilepsy cases in those over age 65.
Dementia is a leading cause of epilepsy among older adults.
Diseases like meningitis, AIDS and viral encephalitis can cause epilepsy.
Prenatal injury. Fetuses are susceptible to brain damage caused by an infection in the mother, poor nutrition or oxygen deficiencies. This can lead to cerebral palsy in the child. About 20 percent of seizures in children are associated with cerebral palsy or other neurological abnormalities.
Developmental disorders. Epilepsy can be associated with other developmental disorders, such as autism and Down syndrome.
Signs & Symptoms of Epilepsy
Because epilepsy is caused by abnormal activity in brain cells, seizures can affect any process your brain coordinates. A seizure can produce:
A staring spell
Uncontrollable jerking movements of the arms and legs
Complete loss of consciousness
Symptoms vary depending on the type of seizure. In most cases, a person with epilepsy will tend to have the same type of seizure each time, so the symptoms will be similar from episode to episode. Doctors classify seizures as either partial or generalized, based on how the abnormal brain activity begins. In some cases, seizures can begin as partial and then become generalized.
When seizures appear to result from abnormal activity in just one part of the brain, they're called partial or focal seizures. These seizures fall into two categories.
Simple partial seizures. These seizures don't result in 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 part of the body, such as an arm or leg, and spontaneous sensory symptoms such as tingling, vertigo and flashing lights.
Complex partial seizures. These seizures alter consciousness, causing you to lose awareness for a period of time. Complex partial seizures often result in staring and no purposeful movements — such as hand rubbing, twitching, chewing, swallowing or walking in circles.
Seizures that seem to involve all of the brain are called generalized seizures. Four types of generalized seizures exist.
Absence seizures (also called petit mal). These seizures are characterized by staring and subtle body movement, and can cause a brief loss of consciousness.
Myoclonic seizures. These seizures usually appear as sudden jerks or twitches of your arms and legs.
Atonic seizures. Also known as drop attacks, these seizures cause you to lose normal muscle tone and suddenly collapse or fall down.
Tonic-clonic seizures (also called grand mal). The most intense of all types of seizures, these are characterized by a loss of consciousness, body stiffening and shaking, and loss of bladder control.
Diagnosis of Epilepsy
Your doctor may use a number of tests to diagnose epilepsy, from neurological exams to imaging techniques like MRI scans.
Neurological and behavioral exam. Your doctor may want to test your motor abilities, behavior and intellectual capacity to see how the seizures are affecting you.
Blood tests. Your doctor may take a blood sample to check for signs of infections, lead poisoning, anemia or diabetes, which can cause seizures.
Your doctor may also suggest tests to detect abnormalities within the brain. These include:
Neuropsychological tests. This group of tests includes IQ, memory and speech assessments, which help doctors pinpoint where the seizures are originating. This type of testing is routinely done before epilepsy surgery.
Electroencephalogram (EEG). This is the most common test to diagnose epilepsy. An EEG records the electrical activity of your brain via electrodes affixed to your scalp. If you have epilepsy, it's common to have changes in your normal pattern of brain waves, even when you're not having a seizure. Your doctor may want to monitor you on video while conducting an EEG of you awake or asleep in hopes of recording the seizure to see what kind of seizures you're having. Sometimes your doctor will have to do something to provoke a seizure while you're being tested, such as asking you to sleep very little the night before.
Computerized tomography (CT). You might be given a CT scan if you go to an emergency room for an initial seizure, because it's generally a readily available test. CT machines use a type of X-ray equipment to obtain cross-sectional images of your brain and skull. CT scans can reveal abnormalities in the brain that might be causing your seizures, including tumors, bleeding and cysts.
Magnetic resonance imaging (MRI). An MRI provides much the same type of information as a CT scan, but in far greater detail. MRIs use radio waves and a strong magnetic field to produce detailed images of your brain. MRIs can reveal brain abnormalities that could be causing your seizures.
Functional MRI (FMRI). A functional MRI measures the changes in blood flow that occur when specific parts of your brain are working. Doctors generally use an fMRI before surgery to identify the exact locations of critical functions, like speech, so that surgeons don't injure those places while operating.
Positron emission tomography (PET). PET scans use a small amount of low-dose radioactive material that's injected into a vein to help visualize active areas of the brain and detect abnormalities.
Single-photon emission computerized tomography (SPECT). This type of test is used primarily if you've had an MRI and EEG that didn't pinpoint the location in your brain where the seizures are originating. A SPECT test uses a small amount of low-dose radioactive material that's injected into a vein to create a detailed, 3-D map of the blood flow activity in your brain during seizures.
Treatments of Epilepsy
Doctors generally start by treating epilepsy with medication. If that doesn't work, they may propose surgery or another type of treatment.
Most people with epilepsy can become seizure-free by using a single anti-epileptic drug. Others can decrease the frequency and intensity of their seizures. More than half the children with medication-controlled epilepsy can eventually stop medications and live a seizure-free life. Many adults also can discontinue medication after two or more years without seizures. Finding the right medication and dosage can be complex. Your doctor likely will first prescribe a single drug at a relatively low dosage, and may increase the dosage gradually until your seizures are well controlled. If you've tried two or more seizure medications without success, your doctor may recommend trying a combination of two drugs. All anti-seizure medications have some side effects. Mild side effects include:
Loss of bone density
Loss of coordination
More severe but rare side effects include:
Suicidal thoughts and behaviors
Inflammation of certain organs, such as your pancreas
To achieve the best seizure control possible with medication:
Take medications exactly as prescribed.
Always call your doctor before switching to a generic version of your medication or taking other prescription medications, over-the-counter drugs or herbal remedies.
Never stop taking your medication without talking to your doctor.
Notify your doctor immediately if you notice new or increased feelings of depression, suicidal thoughts or unusual changes in your mood or behaviors.
Half of all people newly diagnosed with epilepsy will become seizure-free with their first medication. If anti-epileptic medications don't provide satisfactory results, your doctor may suggest surgery or other therapies.
Surgery is most commonly done when tests show that your seizures originate in a small, well-defined area of your brain that doesn't interfere with vital functions like speech, language or hearing. In these types of surgeries, your doctor removes the area of the brain that is causing the seizures. If your seizures originate in a part of your brain that can't be removed, your doctor may recommend a different sort of surgery where surgeons make a series of cuts in your brain. These cuts are designed to prevent seizures from spreading to other parts of the brain. Although many people continue to need some medication to help prevent seizures after successful surgery, you may be able to take fewer drugs and reduce your dosages. In some cases, surgery for epilepsy can cause complications such as permanently altering your cognitive abilities. Talk to your surgeon about his or her experience, success rates and complication rates with the procedure you're considering.
Vagus nerve stimulation. This therapy involves a device called a vagus nerve stimulator that's implanted underneath the skin of your chest like a pacemaker. Wires from the stimulator are wrapped around the vagus nerve in your neck. The battery-powered device delivers short bursts of electrical energy to the brain through the vagus nerve. It's not clear how this inhibits seizures, but the device can reduce seizures by 30 to 40 percent. Most people still need to take anti-epileptic medication. Side effects of vagus nerve stimulation include hoarseness, throat pain, coughing, and shortness of breath, tingling and muscle pain.
Ketogenic diet. Some children with epilepsy have been able to reduce their seizures by maintaining a strict diet that's high in fats and low in carbohydrates. This diet, called a ketogenic diet, causes the body to break down fats instead of carbohydrates for energy. Some children can go off the ketogenic diet after a few years and remain seizure-free. Consult a doctor if you or your child is considering a ketogenic diet. It's important to make sure that a child doesn't become malnourished when taking the diet. Side effects of a ketogenic diet may include dehydration, constipation, slowed growth because of nutritional deficiencies, and buildup of uric acid in the blood, which can cause kidney stones. These side effects are uncommon if use of the diet is properly and medically supervised.
When to seek Medical Advice
Seek medical advice if you experience a seizure for the first time. Also, seek immediate medical help if any of the following occurs.
The seizure lasts more than five minutes.
Breathing or consciousness does not return after the seizure stops.