Kathryn Loder had to be hospitalized after becoming seriously ill during the shooting of this film. Loder slipped into a coma while being treated at the hospital and almost died. Fortunately, the doctors discovered that Loder had diabetes and gave her insulin treatment which enabled her to make a complete recovery.
None of the extras were told they were going to be squirted with fire hoses during the filming of the cafeteria food fight set piece.
Director Jack Hill named the sadistic prison warden "Dietrich" after German producer Erwin C. Dietrich, with whom Hill had had a very unpleasant experience after Dietrich hired him to shoot a film in Switzerland.
A graphic lesbian scene was shot, but cut from the final finished version of the film.