Angelina Jolie said about her character Gia: "When she's free and just being herself, she's unbelievable. That's the tragedy of her story. You think, 'God, she didn't need drugs. She was a drug.'"
Elizabeth Mitchell's character Linda is a fake name for real-life makeup artist (and Gia's once-girlfriend) Sandy Linter.
Angelina Jolie's brother James Haven can be seen briefly leaning up against the wall in the beginning of the film when she and TJ are going into the tattoo parlor.
Angelina Jolie originally rejected the role, admitting she knew it would "really mess with me and drive me a bit nuts to be that open." When she first began her research and saw a 20/20 interview in which Gia had the addled speech of a junkie, Jolie hated her. But later, after throwing herself deep into the role, she said, "I'd like to date Gia. I'd want to be her lover."
Angelina Jolie found the intensity of playing a drug-addicted lesbian so extreme that she deliberately sought out a "normal" heterosexual role for her next film. That proved to be Mike Newell's Pushing Tin (1999).