Originally, the book that suicidal students supposedly underline "meaningful" passages from was "The Catcher in the Rye." The producers could not get permission from J.D. Salinger to use the book. It was changed to "Moby Dick" because Herman Melville's works are in the public domain.
Shannen Doherty had problems saying the profanities in the script because of her conservative upbringing. She couldn't keep a straight face. As a result, she smirks when she says, "Veronica, why are you pulling my dick?"
The same week Winona Ryder received the script, a student from her high school committed suicide, which only inspired her more to do the film.
Christian Slater has stated that his performance was heavily inspired by Jack Nicholson. He claims that he wrote a letter to Nicholson asking him to watch the film but did not receive an answer.