Does Epilepsy In The Long Run Cause Memory Issues?

Hi, my mother was diagnosed with epilepsy about 10 years ago. She was prescribed to take phenytoin three times a day and has done so accordingly. However, recently I noticed her symptoms getting worse and discovered that she hasn t been taking her medication regularly. When I ask her she says she is taking it regularly and I was wondering if the disease makes her forget things and that she is forgetting to take her medication.