I ve been taking Flecainide since 12/20/16, when I suddenly had a severe increase with Afib issues. I ve noticed a general increase in memory problems, but occasionally I ve felt strange mentally. This varies from a vague feeling, to occasionally I can t think or function. I can t drive when this happens. I do have some leg cramps at night, & some strong irritability at times. I m wondering if I m having a side effect of the medication, or low potassium, or WHAT?!