According to The Hollywood Reporter, the thriller has been a weak link in its Friday night lineup.
Series creator Glenn Gordon Caron announced the news online: "It's true. Allison Dubois will dream her last dream on Fri 1/21. In what we believe will be a series defining episode, Allison and her family will stare destiny in the eye. And destiny will not blink."
CBS rescued Medium from cancellation after NBC axed the program last year, but last month the network declined to pick up the show's nine episodes for the season.