On January 14, 2008 Dr. Steven Schachter was guest expert for a question and answer chat on seizure medicines. The purpose of this session was to provide general information and resources. These answers and the information on epilepsy.com are not intended to be medical advice. People are encouraged to direct specific questions to their own doctor for medical advice.

Dr. Schachter is the Editor-in-Chief of epilepsy.com and Vice-President of Medical Information for the Epilepsy Therapy Project. He is also Editor of the medical journal Epilepsy & Behavior, Professor of Neurology at Harvard Medical School and an epileptologist at Beth Israel Deaconess Medical Center in Boston, Massachusetts.

Question: The first question pertains to the use of Depakote and Lamictal together in children. Do you have any thoughts in regards to dosing of these medicines?
Answer - Dr. Schachter: These medicines can be used in children with caution. This is particularly important with this combination because if Lamictal is added to Depakote, there is a risk of serious rash from Lamictal. However, rash is less likely to occur when low dosages of Lamictal are used to start and the dose is increased slowly over time. The dosages for children will often be different than the doses used in adults, because kids’ bodies break down the medications differently than adults. In the section on AEDs (antiepileptic drugs) on epilepsy.com, we have a section for use of each AED with regard to children. That’s a good place to check.

Question: Could you explain ways that people can lessen side effects of seizure medicines?
Answer- Dr. Schachter: There are several possible approaches to reducing side effects. But first, discuss the specific symptoms with your doctor to be sure they are side effects and if they are, then ask which of the following approaches makes most sense. First, the total dose for the day can be reduced. Second, the amount of the drug taken at any one time of day can be reduced. Third, the dose can be taken with food.

Question: One side effect that bothers people is weight gain. Do you have thoughts on which drugs would cause weight gain and which may cause weight loss?
Answer- Dr. Schachter: Most people do not gain or lose weight from seizure medications or AEDs. The AEDs that most commonly lead to weight gain are Depakote, Neurontin, and Lyrica. The AEDs that most commonly lead to weight loss are Topamax and Zonegran. My experience is that discussing this issue with your doctor is a good thing. The doctor might take your concern into account when prescribing AEDs. Or the doctor might recommend a diet, whether to lose weight or to add extra calories if necessary.

Question: Sometimes people notice that seizures increase after starting a new drug. Earlier a user raised a concern about seizures increasing after starting Keppra. Do you have thoughts on this?
Answer- Dr. Schachter: In general, AEDs don’t usually cause seizures to increase, but in individual circumstances this is a possibility. More likely is that the AED is not effective for stopping seizures at the current dose. Be sure to discuss with your doctor that the medicine isn’t yet working and to get specific instructions on dosage changes. Another possibility is that the chosen AED is not the best one for the type of seizure it is being prescribed for, in which case the doctor might recommend trying a different AED.

Question: After 40 years on Dilantin, a person was gradually switched to Keppra. Four months after starting Keppra, the person had to have laser surgery on their eyes for ‘narrow channels’ to prevent narrow angle glaucoma. Have you ever heard of a Keppra connection to this?
Answer- Dr. Schachter: I have not heard of Keppra being associated with a form of glaucoma. This is a possibility for another AED, Topamax. However, if someone has an unusual or unexpected side effect from any AED, I would encourage that person and/or his or her physician to report it on Medwatch. Medwatch is the FDA (Food and Drug Administration) system for collecting this type of information.
You may find information about Medwatch and how to report problems with unexpected side effects to www.fda.gov/medwatch/.

Question: Do Zonegran and Topamax work together?
Answer- Dr. Schachter: Most combinations of AEDs can work together. Sometimes caution is needed because there are always a couple of considerations for doctors to think about. The first question is if one AED affects the amount of the other in the body. The second question is whether the side effects of the drugs “add” together to cause worse side effects than either one alone.We have a lot of information about drug-drug interactions on epilepsy.com. In the case of Zonegran and Topamax, they each can cause weight loss, and they each can cause kidney stones, though this occurs in less than 5% or so of people. So, I would be on the lookout for both of these possibilities with this combination.

• For general information on drug interactions visit http://www.epilepsy.com/epilepsy/medicine_interactions
• For information on specific drugs, see the downloadable sheet for each drug that can be found at http://www.epilepsy.com/medicine_sheets.
• For detailed information on drug interactions for specific drugs, visit the epilepsy.com professional site and download a copy of the desired AED Interaction Sheet found in the Document Library at http://professionals.epilepsy.com/page/doclib.html.

Question: What about myasthenia and Dilantin? A user reported having myasthenia in the eyes and was told that Dilantin may be the cause.
Answer- Dr. Schachter: Myasthenia is a muscle condition that can affect the eyes, usually causing weakness of the eyelids or double vision. To my knowledge, Dilantin has not been linked to myasthenia. But again, I encourage the use of Medwatch to report unusual or unexpected side effects of a particular AED.

Question: Lots of people write about Keppra affecting their moods. Do you think there is a relationship?
Answer- Dr. Schachter: Some people who take AEDs, including Keppra, believe it affects their moods. In the case of Keppra, this usually is described as irritability or agitation. As for all possible side effects, discuss this with your doctor to see what he or she recommends that you do with the dosage or how you take the dosage over the course of the day. Be sure that your family members express their concerns too.

Question: Can antidepressants be used along with AEDs? Anything to be aware of?
Answer – Dr. Schachter: Taking antidepressants with AEDs is usually not a problem. This is particularly true for the family of antidepressants called “selective serotonin re-uptake inhibitors”. Some other kinds of antidepressants have been thought to make seizures worse, so check with your neurologist if you are prescribed an antidepressant by another doctor before you start taking the antidepressant.

Question: Can Topamax affect mood?
Answer- Dr. Schachter: Many AEDs can affect mood as a possible side effect, including Topamax. It’s also possible that mood changes might be unrelated to AEDs. People with epilepsy should discuss their moods with their doctor to evaluate whether they are related to AEDs, the epilepsy, or something else.

Question: A user was just diagnosed with epilepsy and is now on Topamax. He had been having a really bad taste in his mouth – could this be related to the Topamax or the epilepsy?
Answer – Dr. Schachter: Epilepsy usually doesn’t affect taste in the mouth. If a person chews a pill that is meant to be swallowed whole, it could cause a bad taste. The same thing may occur with opening a capsule in the mouth. Another possibility is that the AED may cause a dry mouth, which can affect taste. Some antidepressants can also cause a dry mouth.
Epi_help: if a bitter taste occurs after swallowing Topamax tablets, try drinking a full glass of water with the pills.

Question: Do seizure medicines affect a woman’s hormones or affect puberty in an adolescent girl?
Answer- Dr. Schachter: This is a big topic. Epilepsy can affect hormones, and some seizure medicines can affect hormones. Also, hormones can affect seizures. If a woman’s hormonal function does not appear to be normal, for example menstrual periods are irregular, then a doctor should be consulted to work out the reason. Besides possibly affecting hormones, some AEDs may affect the strength of oral contraceptives for the same reason, which could make the contraceptives too weak to prevent pregnancy. The AEDs most likely to affect oral contraceptives include Dilantin, Tegretol, Carbatrol, Topamax, Trileptal, Phenobarbital and Mysoline.

Question: Here’s a question that can affect anyone. If someone misses a dose of medicine but doesn’t notice it for a while, what should they do? Should a person wait until the next dose or make it up?
Answer- Dr. Schachter: Good question. It can be hard to take pills at the right times day in and day out. On epilepsy.com, in the download information for each AED, we have a section that describes what to do if a dose is missed.
Epi_help: Here’s a link to questions about missed medicines as possible trigger to seizures - http://www.epilepsy.com/node/186. On each 'Medicine Sheets to Download' found at https://my.epilepsy.com/medicine_sheets, there’s some general info on what to do in relation to the specific drug. However, since each person is different, it’s important for people to talk to their doctor for specific instructions on what to do for their own situation.

Question: How do AEDs affect the liver and kidneys, especially in children?
Answer- Dr. Schachter: AEDs are either broken down (digested) by the liver, or passed through the kidneys (excreted). Under the drug information for each AED on epilepsy.com, we say how each drug is digested in the body. When an AED is broken down by the liver, it may cause blood tests from the liver to go up. The doctor should be asked whether the liver blood tests have gone up, and if so, what to do about it, if anything. The meaning of the elevation in liver tests depends on how much they are elevated. Generally, a slight elevation (or increase) does not mean that the AED is causing any harm to the liver. However, a moderate to high elevation could be an indication that it is, and should be discussed with the doctor.

Question: How often should people taking seizure medicine get blood tests done, and what tests do you recommend? Do the tests differ for different medicines?
Answer- Dr. Schachter: Blood tests can be helpful for several reasons. First, it can indicate whether the AED is affecting the liver, as we just talked about. Second, it can indicate if the AED is affecting other systems in the body, such as substances in the blood called electrolytes (for example, sodium) or the bone marrow, which produces blood cells. The need for blood tests, and the frequency of blood tests, depends on which AED is being taken, and whether any abnormalities have already been found.

Question: A user asked a general question about seizure symptoms. Can someone remain conscious during a complex partial seizure?
Answer- Dr. Schachter: The term “complex partial seizure” means, by definition, that consciousness is altered so much that the person is out of contact with their surroundings during the seizure. The term “simple partial seizure” means that consciousness is not affected during the seizure. “Consciousness” usually means that the person having the seizure remembers everything that took place during the seizure. Losing consciousness usually means loss of memory during the seizure. However, the important thing is learning how to protect your safety during the seizure. Be sure that others know what you can and cannot do, see, hear or feel during your seizures or the recovery period.

Question: A user asked about being able to hear but not respond during a seizure. Can you talk about this?
Answer- Dr. Schachter: Being able to hear and remember everything -- but not able to respond -- probably indicates that it wasn’t a complex partial seizure.
Epi_help: Here’s a link to epilepsy.com’s seizure preparedness section that has information on observing and responding to seizures and developing plans on how to manage them. http://www.epilepsy.com/epilepsy/preparedness

Question: What does half-life of a medicine mean?
Answer- Dr.Schachter: Half-life means that (or refers to) the amount of time it takes for the amount of medicine in the blood stream to go down by 50% without any more medication being taken. If a person has a Dilantin level of 10, and 12 hours later the level is 5 (assuming that no more Dilantin was taken), then that person’s half-life of Dilantin is 12 hours. Why is this important? When starting a new drug, or taking a new dose of a drug, it takes 5 half-lives before the level of the drug in the body balances out. Each AED has a different half-life, so the period corresponding to 5 half-lives will be different from one AED to the next. Your doctor should be able to tell you how long this will be.

Question: Is there a way to know if seizures are occurring but being controlled by medicines?
Answer- Dr. Schachter: We usually assume that medicines are completely controlling seizures if no seizures are experienced by the person with epilepsy or observed by others. It is possible for there to be a type of seizure activity without obvious symptoms being felt or observed. However, this requires prolonged EEG monitoring to determine, and the significance of this has to be evaluated on a case by case basis.

Question: What about stopping medicine? When would this be indicated and under what conditions could medicines be stopped?
Answer- Dr. Schachter: Whether, when, and how to stop seizure medicines is an important but complicated topic. The discussion is best had with your doctor. The factors that go into the discussion are numerous. They include:

• the type of epilepsy someone has,
• how many seizures occurred before AEDs were started,
• how long it took for the seizures to come under control,
• how long the person has been on AEDs,
• the cause of the epilepsy,
• and perhaps most importantly- the consequences of what might happen if seizures come back once AEDs are stopped.

Summary:

This Q & A session raised important concerns from users about seizure medicines. We hope that the information offered by Dr. Schachter will help users better understand seizures medicines. Since medicines are the mainstay of epilepsy treatment for so many people, it is critical that people talk to their doctor about their concerns, how medicines affect them, and for individual medical advice.

We hope this chat has been helpful and look forward to doing this again! If you have topics you would like to have addressed in Q & A Chats, please email patty@epilepsytdp.org.