Try the epilepsy (http://ohsam.livejournal.com/tag/epilepsy) and seizures (http://ohsam.livejournal.com/tag/seizures) tag at ohsam for starters. There are also a few fills at a comment-fic meme (http://ratherastory.livejournal.com/201862.html) I held at my LJ at the beginning of the season which have Sam with seizures.

There's also spn_littlebro's fantastic Delicious archive: http://www.delicious.com/spn_littlebro/h%3Dseizures and

Also I have a couple of stories in which Sam has epilepsy and/or seizures: my After the End (http://ratherastory.livejournal.com/tag/after%20the%20end) 'verse, and my 2010 Big Bang, Nihil Inherit (http://ratherastory.livejournal.com/60075.html).

Hope this helps!

Wow! Thanks so much! This should keep me busy for a while. Also, now that I think about it, I haven't checked out any of your newer stuff lately. Now I'll be really busy.

Thank you Thank you Thank you!

ratherastory rec'd about everything I would have!

I would also like to add my Seizure!Sam (https://delicious.com/cherry619/seizure!sam) and Seizure!Jared (https://delicious.com/cherry619/seizure!jared) tags on my delicious.

Thanks! We have the exact same taste in storie. I should have known to check there.

Potter´s Clay on ff.net
After their Dads death the boys find out that they have another brother, Adam. They go find him and so on ;D Sam´s mentally challenged in this fic and has seizures.
I liked the story very much

One of my favorites! I actually just re-read it so thanks!