Watching someone have a seizure can be a terrifying experience. One minute you may be chatting with a colleague and the next minute, they have lost consciousness and begun making jerky movements. While not all seizures are this severe, some people with epilepsy—a brain disorder in which nerve cells send the wrong signals—find that their daily lives are seriously affected by the possibility that they might have a seizure.

More than two million Americans have had an unprovoked seizure or been diagnosed with epilepsy. Fortunately, the majority of these people gain control over their seizures with epilepsy mediations, though treatment doesn't always work for everyone. Below, William Rosenfeld, MD, director of the Comprehensive Epilepsy Care Center for Children and Adults in St. Louis, Missouri, discuss new and older medications for epilepsy.

What is epilepsy?
Someone is diagnosed with epilepsy when they have two or more seizures in their life that are not related to alcohol or drug withdrawal or a high fever. It's a very common disorder. It occurs, on a conservative estimate, in at least 1 percent of the US population.

What causes epilepsy?
There are many different reasons that seizure disorders occur. Sometimes it is due to genetics. Sometimes it is due to trauma, either in utero, at birth or in the ensuing years. Sometimes a high fever causes seizures. When we get into adulthood, especially the teenage years, epilepsy is often caused by trauma—automobile accidents, head injuries and gunshot wounds.

As they get older, some people develop epilepsy due to vascular disease, strokes, tumors and Alzheimer's disease. But more than half the time we never know clearly what is the cause of the epilepsy.

What kind of seizures do people have?
Many people are familiar with the grand mal or generalized tonic-clonic seizure because it's the most dramatic. It comes from the French and means "big, bad seizure." With a grand mal seizure, someone may fall to the ground and have generalized stiffening and jerking of the body. Sometimes a patient will bite their tongue or have some loss of urine.

But there are many other seizures that occur. When there's no alteration or loss of consciousness, it is called a partial simple seizure. With those seizures, sometimes the patient may just get a funny feeling in an arm or a leg, or get an urge to go the bathroom, or have some visual or auditory hallucinations.

If there is an alteration or loss of consciousness, that's what we call a partial complex seizure. People may simply stare straight ahead. Many times, the person will have some lip-smacking, automatic movements, picking at their clothing, or turning to one side or the other. But they don't fall to the ground. It's simply an alteration of consciousness. Most of those seizures last anywhere from 50 to 90 seconds, and then the person will gradually recover.

Some people can start by having a partial seizure and then it will spread to a generalized tonic-clonic seizure. In adults, probably 75 to 85 percent of all seizures start as partial seizures. Many times people don't notice the early part of the seizure, and they just see the grand mal or generalized tonic-clonic portion.

You can also have generalized tonic-clonic or grand mal seizures that don't start as a partial seizure. More of those are genetic in nature. Afterwards, the patient may be lethargic for a while. Some may take 20 or 30 minutes to fully recover from the seizure.

Are there trigger factors?
Seizures may occur at any time, but clearly there are certain things that seem to trigger seizures. Sleep deprivation is a common factor that may worsen folks' seizures. In fact, when we're trying to diagnose somebody with a seizure disorder, we often may do a sleep-deprived EEG (electroencephalogram), which traces brain waves.

Stress may precipitate some seizures. That's not to say that if you simply have stress, you're going to have a seizure. But if you're someone with a seizure disorder, and you're particularly stressed and anxious about things, that can precipitate seizures.

Alcohol and drugs may trigger seizures, and they may also interfere with some of the medications, especially the older medications that are mostly broken down by the liver. For example, if you drink, often the next day the liver is full of alcohol, so you can't break down your seizure medicine.

When does epilepsy usually occur?
Epilepsy can occur in any age group. One of the most common times is in early childhood, between birth and 10, 12 years of age. There's another common age group that people are not always aware of: the elderly. Those who are 65 and above are the fastest growing population for new onset of epilepsy.

What are the goals of therapy?
The ideal goal for the treatment of epilepsy is to control the seizures. That's of paramount importance. The medicines we currently have can't cure the epilepsy. In some cases you can cure the epilepsy with surgery. That is something that is done usually only if you haven't responded to a number of anti-epileptic drugs.

In addition to being seizure-free, you'd like the medication schedule to be as easy to follow as possible, meaning you don't want to have to take a drug three or four times a day. Once you start getting past about two times a day, people often start to forget their medications. So you'd like to be on monotherapy, meaning one-drug therapy, if at all possible. With one drug, there is less potential for side effects. But sometimes you have to use combined therapy to get control of the seizures.

What are the most common older drugs for epilepsy?
The most common seizure medicines have been phenobarbital and phenytoin (Dilantin). Phenobarbital dates back to 1912 and phenytoin dates back to 1938. Because of the length of time they've been out, people know a lot about them. However, drugs such as phenobarbital, while they control many patients' seizures, also have significant side effects. A lot of people get slowed by phenobarbital in terms of their cognition, and also get some depression.

Phenytoin, is also a very good anti-epileptic drug that also has side effects. Since the drug is metabolized mainly through the liver, there's a chance of liver problems and interactions with other medicines. And it can also cause problems with calcium and with vitamin D levels, so patients' bones could thin, leading to osteoporosis. Phenytoin may also have cosmetic side effects such as the coarsening of facial features, overgrowth of the gums and the mouth, and sometimes excess hair. I would also put carbamazepine (Tegretol, Carbatrol), and valproate (Depakote, Depakene) into the category of older medications because they came out in the 1960s and '70s.

Perhaps 40 to 50 percent of folks are controlled with one of these older drugs.

What are some of the newer drugs for epilepsy?
There have been about seven new drugs that came out in the '90s. These are gabapentin (Neurontin), lamotrigine (Lamictal), tiagabine (Gabitril), and topiramate (Topamax). Since about 2000, we've had oxcarbazepine (Trileptal). We also have levetiracetam (Keppra) and zonisamide (Zonegran).

I think that some of the newer anti-epileptic drugs are less likely to cause both short-term and long-term side effects. The newer drugs are mostly excreted by the kidneys, rather than through the liver. So there will be fewer problems in terms of interactions through the liver with the other medications that people might be taking.

Also, many of the newer drugs require fewer doses. The goal is to try to go from multiple daily doses and get to at most, twice a day dosing, although there are a couple of the newer drugs that were more three or four time a day dosing.

How would one initiate the monotherapy?
Whenever possible, you'd always like to go for monotherapy right from the start, assuming the drug is effective and that it's either in the approved labeling or you've reviewed it with the patient. When someone is on one drug and I can't get success with it, I add a second. I don't simply add the second and remove the first drug. I wait to see over perhaps six weeks, eight weeks, how well the new drug is doing. If the new drug is then doing well, I try to slowly taper the other drug off to convert the patient to monotherapy.

The difficulty in converting to monotherapy depends on the patient's seizure disorder. Some people, start to have more seizures. But in many cases it really is quite doable, and it's simply a process that you have to set up with your patient.