Antiepileptic Therapy Adverse Effects and Nonadherence

Amit Verma, MD: There are some adverse effects that are common to all antiepileptic medications. Those would be things like the risk of depression and suicidal ideation, which is common to all antiepileptic medications. That’s considered a class effect. Anytime we make changes to the person’s antiepileptic medication regimen, we talk to the patients and the caregivers about mood issues and depression. If they experience mood issues once a medication has been initiated, we ask the patients to inform us, so we can take corrective measures.

Other adverse effects that tend to be very common with antiepileptic medications include things like risk of somnolence or sedation. Especially with perampanel, there is a risk associated with falls or gait disturbances, so we go through all those things. In the clinic, we mostly discuss the black box warning. We discuss the common central nervous system–type adverse effects and then always tell the patients to inform us if anything unusual happens or if there’s something that’s going to impact their ability to work or their ability to function in society. If they notice any changes whatsoever, we typically encourage them to inform us of those as well.

Medication adherence is a common problem in patients who have epilepsy. Going back several decades, there were some good studies that looked at the risk of patients missing their doses based on the frequency of dosing per day. The best adherence seems to be with medications that patients have to take only once per day. The way I encourage patients to think about medication adherence is this: None of us is a robot. There are going to be times when the patients will forget whether they’ve taken their medication. If they have a seizure, that might make them confused, so they don’t know if they’ve taken their medication or not. I typically recommend that all patients have a pillbox where they can fill it for the month. This way, if they don’t remember whether they’ve taken their medication, they can look in the slot for that pillbox and easily see whether the dose was taken. I recommend that everybody who has epilepsy has a pillbox so that they can be as adherent to their medication regimen as possible.

Common triggers would be that if they have a seizure, they might not remember. Many patients who have epilepsy often have cognitive or memory issues, so they might not remember to take their medication because of their underlying cognitive issues. Aside from this, there are going to be times when the patient is traveling, and they might not remember to take their medication with them. There are some patients who, if they are unable to get their medication, are going to start skipping doses so they can maintain some continuity of management until they’re able to get their prescription filled. There are many reasons a patient may not be able to adhere to their regimen, but having the pillbox will make a big difference to the overall treatment for that patient.

All these issues can contribute to the patient not being adherent. Younger patients tend to forget their medications much more than older patients. If a younger patient is out in the evening and they’re supposed to take their medication, they may come back and go to sleep. If somebody is older, there could be issues in terms of caregivers giving them their medication, so that’s another thing we have to think about. Complexity of home life also matters; if there are stressors in their life or if there are issues where they’re not able to get their medication because a caregiver is not available, then those factors are going to impact adherence for the patient.

In terms of the stress of a schedule, if patients are taking medications multiple times per day, especially if they’re at work and they’re given a medication that is taken 3 times a day, then it’s going to be difficult for them to remember to take that afternoon dose. Again, the simpler we can make the medication regimen, the better off the patients will be because they’ll be more likely to take their medication at that point.