I don't know either. I know sometimes they discover other uses for a drug when they are prescribed off-label. Sometimes they just notice a drug also has another unintended effect that is good for something else. I'm not sure they can always say just what is causing that or not. The same way they sometimes say, we know this drug works, but we don't know why.

I take Lamictal for BP and it works well for me. Keeps me on a mostly even keel and regulates my sleep. Only negative side effect I've had is that I get really bad heartburn for a few days each time my dose is increased. Other than that, it's been a pretty good pill for me. Got no experience with it for seizure disorder, though. You might try the next Friday afternoon chat with the pharmacology guru psisci. He might have an answer for you.