UPDATE: It seems Kelly Osbourne is feeling better, as she confirmed the news and tweeted this message to her fans from the hospital:
Thank U all 4 UR beautiful well wishes yes I did have a seizure they are just trying to figure out why?
Kelly Osbourne has suffered a seizure while filming on the Los Angeles set of her E! TV show Fashion Police and has been rushed to a local hospital, Entertainment Tonight reports.
The seizure, which lasted 30 seconds, caused Kelly to fall to the floor, where crew members and an EMT in the audience rushed to her aid. When she awoke she was covered in blankets and taken out of the studio to an ambulance that rushed her to an area hospital. The seizure happened at the end of an hour-long taping.
Check back to Fuse for more as this story develops...