Rani, who had gone to the show to promote her upcoming film "Hichki", was preparing to shoot with show judges, directors Karan Johar and Rohit Shetty, when she felt the "excruciating" back pain, a source from the sets said.
"Rani has been in excruciating pain for the past three days. She is a thorough professional and despite her back issue she landed up on the sets of 'India's Next Superstar' today.
"She was getting ready to shoot with her best friend Karan Johar and Rohit Shetty and that's when she again felt a surge in pain. She couldn't move. Her pain was excruciating again and unfortunately she had to rush home to be attended by her doctor. We hope she gets well soon," the source said.