According to The New York Times, representatives of the lead actress are in negotiations with the show's lawyers and producers to work out an exit agreement.
Mendoza portrayed the villain Arachne in the $65 million (£42.3m) production, an original creation of helmer Julie Taymor. The actress - who previously suffered a concussion on set - has not performed since fellow cast member Christopher Tierney was seriously injured in a fall during a preview show.
Reports suggested that she has been on vocal rest under doctors' orders. Her understudy America Olivo is expected to take up the role of Arachne.
Turn Off The Dark was originally scheduled to commence in March 2010, but financial problems, cast departures and four injuries on set delayed its production. The show has been criticised by Broadway actors and sections of the media.
The musical is expected to open on February 12, 2011.