Epilepsy : Controlling Seizures

by Food and Drug Administration (FDA)

(Page 3 of 3)

Diagnosing and characterizing epilepsy in people is a multi-step process. A person first must be confirmed to have had at least two or more epileptic seizures. Once the diagnosis of epilepsy is made, the patient's seizure type is characterized. A clinician then must determine whether the patient's seizure disorder conforms to a particular type of epilepsy or epileptic syndrome, and a clinical investigation targeting the cause of the epilepsy is conducted. Based on this and other information, the most appropriate therapy is selected.

Anti-epileptic drugs best treat the symptoms of epilepsy, but they do not cure the disease. The goal of treatment, says John Feeney, M.D., neurology team leader in the FDA's Division of Neurology Products, is to decrease the number and severity of seizures and minimize drug side effects. Since 1990, a large number of new anti-epileptic drugs have been approved, increasing the treatment options for patients and their doctors. But Feeney says it's important to remember that all the drugs, even the new ones, have some side effects. "Anti-epileptic drugs are centrally active on the nervous system," he says, "so you could expect that they would be associated with such side effects as dizziness or drowsiness."

How well an epilepsy drug works may be affected by other drugs a person is taking. Known as drug interaction, this relationship may involve how the drug is absorbed, metabolized, and otherwise distributed in the body. The interaction, for example, may speed up or slow down how quickly an epilepsy drug is eliminated, either making it less effective at preventing seizures because a lower level is present in the blood, or more likely to build up to toxic levels and cause side effects.

Some of the newer treatments do not interfere with the body's metabolism when taken in combination with other epilepsy drugs. The FDA says that studies have indicated that because some newer treatments are not metabolized through the liver, they are less likely to cause interactions with other epilepsy drugs or commonly used drugs, such as oral contraceptives. This makes them an attractive alternative for those needing more than one anti-seizure medication.

When a person starts a new epilepsy drug, according to the NINDS, it's important to tailor the dosage to achieve the best results. Feeney adds that patients react to medications in different and sometimes unpredictable ways. He says that it may take some time to find the right drug at the right dose to control seizures, while minimizing any side effects. "Certain seizure types seem to respond to some drugs better than others," he says. "Why this is so isn't fully understood."

Mielenhausen says her son is such a case. "The first medication we tried made things worse for Mike," she says. Besides the seizures occurring more frequently, Mike exhibited profound mood swings. And the medication had a sedative effect on him. "It's been a roller coaster at times," Mielenhausen says, "but we also have a lot to be thankful for." Once Mike was tapered off the first medication and was prescribed one that worked, things got better. His seizures occurred less frequently with minimal side effects. "We've gotten to know many families who have a much harder time with seizure control," she says, "and it helps us to keep that in mind."

"Some people will do reasonably well on just one drug," Feeney says. In many other cases, several anti-seizure medications are required to stop the seizures. In fact, Feeney adds, "clinical trials done to support approval of new drugs are usually done on people taking more than one epilepsy drug."

The Epilepsy Foundation adds that people who are being treated with anti-epileptic drugs may sometimes need periodic blood tests to determine whether they are getting enough medication and to check for adverse effects on the liver or the blood. Achieving the best seizure control possible, experts say, depends on taking the same amount of the medicines every day that have been prescribed by a doctor.

Scribner hasn't had a seizure in over a year. He believes that his last one was brought on by his having forgotten to take his medication. "That's why people with epilepsy shouldn't take themselves off their medicines, even though they appear to be seizure-free," says Scribner, an epilepsy educator at the Epilepsy Foundation.

Other Treatments

When seizures cannot be adequately controlled by medications, doctors may recommend that a person be evaluated for surgery. If a person is considered a good candidate, experts generally agree that surgery should be performed as early as possible.

While surgery can significantly reduce or even halt seizures for some people, it is important to remember that any kind of surgery carries some amount of risk. The Epilepsy Foundation advises people to ask their surgeon about his or her experiences, success rates, and complication rates with the procedure they are considering.

The NINDS also says that even when surgery completely ends a person's seizures, it is important to continue taking seizure medication for a period of time to give the brain time to readjust. As always, people should talk about this with their doctors.

In children, studies have shown that certain types of seizures may respond to a strict diet high in fats and low in carbohydrates. The "ketogenic diet," which is not the same as other popular low-carbohydrate diets, causes the body to break down fats instead of carbohydrates to survive. This condition is called ketosis. Doctors recommend the ketogenic diet for children whose seizures have not responded to several different seizure medicines.

The ketogenic diet is also not easy to maintain, according to the NINDS. It requires strict adherence to an unusual and limited range of foods, usually requiring the help of a dietitian. Possible side effects include retarded growth due to nutritional deficiency and a buildup of uric acid in the blood, which can lead to kidney stones. Children who are on the ketogenic diet also need to take seizure medications.

An implanted device that delivers electrical stimulations to the brain was approved by the FDA in 1997 for use in people whose seizures are not well-controlled by medication. Manufactured by Cyberonics Inc. of Houston, the VNS Therapy system is a battery-powered vagus nerve stimulator that is surgically implanted under the skin of the chest and attached to the vagus nerve in the lower neck. This device delivers short bursts of electrical energy to the brain. Patients usually cannot stop taking epilepsy medications because of the stimulator, but they often experience fewer seizures and they may be able to reduce the dose of their medication.

The FDA reminds people that serious injury or death can occur in those with implanted neurological stimulators who undergo magnetic resonance imaging (MRI) procedures. The mechanism for these adverse events is likely to involve heating of the electrodes at the end of the leadwires, resulting in injury to the surrounding tissue. Therefore, people with implanted neurological stimulators are advised to consider other imaging options.

Epilepsy and Older People

Epilepsy is often considered a disorder of the young, or a disease that people are born with. But according to the National Council on the Aging (NCOA), people can develop epilepsy as they age, and the greatest number of newly diagnosed cases each year occurs in older people. Those older than 65 are the fastest-growing group in America to develop epilepsy.

According to the NCOA, knowing the difference between a "senior moment" and a serious disease such as epilepsy is critical. Epilepsy often develops as a result of common health problems in older people, and physicians face the challenge of simultaneously treating patients for epilepsy as well as for multiple health problems. In these cases, the potential for adverse drug interaction becomes increased.

"Epilepsy is one of the most often misdiagnosed, mistreated, or under-treated conditions affecting seniors," says NCOA President James Firman, Ed.D. The condition often is characterized by recurrent seizures affecting awareness, movement, or sensation. Epilepsy may, however, present itself differently in older people and is often confused with the normal signs of aging. Because epilepsy is more often associated with seizures causing convulsions, the more subtle but potentially dangerous symptoms, such as hearing unusual sounds, blurred vision, or sudden anxiety, are often overlooked.

Although there are a number of effective therapies for treating epilepsy, treating older people poses special challenges. The older anti-epileptic drugs, called first generation, are primarily used to treat the most common type of seizures. But they are far from ideal for older people because, according to the NCOA, these drugs can be difficult to dose accurately, they can interact with other drugs often taken by the group, and they can have side effects such as heart toxicity, weight gain, and bone loss.

Looking to the Future

Scientists continue to study how nerves fire and how non-neuronal cells in the brain contribute to seizures, and researchers are working to identify genes that may influence epilepsy. This information, according to the NINDS, may one day allow doctors to prevent epilepsy or to predict which treatments will be most beneficial. Scientists also are experimenting with several new types of therapies for epilepsy, including transplanting stem cells and using a device that could predict seizures up to three minutes before they begin. This is, however, preliminary research. Much is being done also to improve MRI and other brain scans, and, according to the NINDS, researchers hope to develop implantable devices that can deliver drugs to specific parts of the brain.

What to Do for Someone Having a Seizure

• Roll the person on the side to prevent choking on any fluids or vomit
• Cushion the head
• Loosen tight clothing around the neck
• Keep the airway open. If necessary, grip the person's jaw gently and tilt his or her head back
• Do not restrict the person from moving unless he or she is in danger
• Do not put anything into the mouth, not even medicine or liquid
• Remove sharp or solid objects that the person might hit during the seizure
• Note how long the seizure lasts and what symptoms occurred so you can tell a doctor or emergency personnel, if necessary
• Stay with the person until the seizure ends.

About the Author

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