"We got canceled," the 42-year-old told Entertainment Weekly. The star's comment arrives a month after CBS announced it had cut the supernatural drama's original 22-episode order back to 13 episodes.
Although the network has yet to confirm Medium's fate, Arquette said she's excited to see what is planned for the series finale.
"I was trying to get information from the writers about the last episode," Arquette told the magazine. "I don't know what it's going to be, but they're really excited about it. They're like, 'We're just going to burn the whole thing down!'"
Arquette, who won an Emmy for her performance on the show in 2005, says she's not looking forward to saying goodbye. "It's been a great time. I love that time in my life," she said.
Now in its seventh season, Medium premiered on NBC in 2005 before moving to CBS last year. The series has been averaging 7.1 million viewers on Fridays at 8/7c.