As Carla has said, Epilepsy is nothing to be ashamed of but I do understand that there are mixed reactions to it. I would talk to a supervisor about this if there is a risk that someone might slip you caffeine to see what happens. I think that needs nipping in the bud.
We are always here if you need to talk
Good Morning Turtlegirl,
I too am off of caffeing although it is not because of my seizures and I have never had anyone bother me about it. I would just tell them that it is because of a medical condition and it is really none of their business whether you drink anything with caffeine or not, but if you don't want to be quite so blunt just tell them that it was a personal choice that you made not to drink anything with caffeine. They say that everything is bad for you anyway! If that doesn't work maybe you can talk to your boss and tell him or her that all their questions are making you uncomfortable and could he please talk to them. After all that is the job of a supervisor!