I was flying ATL - FRA.
I'm sitting in my usual aisle seat half way into the flight when I am awakened by a man who has fallen into my lap (face up).
I see his eye lids wide open and his eyes rolled to the back of his head with his mouth open and contorted. Not being used to being awakened quite like this, my reaction is to quickly push him off into the aisle. In a flash, the FA's show up and it is obvious that he is having an epileptic attack. Everybody does what ever they can, and I'm holding him down so he doesn't hurt himself. Very quickly, the attack ends and he jumps up as if nothing happened and walks back to his seat.