I think if they can get a doctor to verify that they are not seizure/blackout-prone, then they can get their license back. You shouldn't be banned from driving your whole life because of a temporary medical condition. But if they are at a significant risk of seizures, then keep them off the roads.

:edit: My ex gf had seizures a couple time due to her cancer medication. She is now perfectly healthy and there's no reason she shouldn't be driving.