I came upon a thought within the backstory I created of a character. Whom has Epilepsy. And then I began to wonder, is Epilepsy lore friendly?

So long as you call it something else.

In my book, anything that adds character to the world is lore friendly. I would make up some religious connotation for the condition, and think about how various Tamrielic cultures would treat it.

If you don't mind some reading: http://www.gamesas.com/topic/1394531-the-dreamweaver/

I don't think there's anything that would contradict an epileptic character. I agree with Sonic Snap that you should come up with a new name and backstory, even if you just reply the classic "sacred sickness" to Tamrielic religion or metaphysics.

I don't see why it isn't. We share several diseases and ailments, ataxia being one. Although what do I know.