'Tim Roth' turned down the role of Johnny Rotten (John Lydon) as he felt the film depicted history that was too recent.
In Alex Cox's previous film Repo Man (1984), a punk at a party in the beginning can be seen wearing a shirt with Sid Vicious on it.
The real Johnny Rotten ('John Lydon' ) dismissed this film as "mere fantasy... the Peter Pan version."
Gary Oldman wore Sid's real chain necklace in the movie. When doing his research, Sid's mom gave him the necklace to wear during filming.
One of the film's trailers was refused certification by the British Board of Film Classification
Chloe Webb and Gary Oldman improvised their dialogue in the scene leading up to Spungen's death. They created their dialogue from archival interviews and other materials available to them.
Gary Oldman had to lose weight to play Sid Vicious, but he lost so much that he ended up in hospital.
Courtney Love auditioned for the role of Nancy Spungen, but was cast as Nancy's friend Gretchen instead. Alex Cox was impressed by Love's audition and considered casting her as Nancy. But the film's investors insisted on an experienced actor for the role. By way of an apology, 'Alex Cox (I)' then cast Courtney Love as one of the main characters in his next movie Straight to Hell (1987).
Sid's mother Anne Beverly initially tried to prevent the movie from being made but after meeting with Alex Cox she decided to help the production.
In his 2007 autobiography, Guns N’ Roses guitarist Slash revealed that the casting director hired all five members of Guns N’ Roses as extras for a club scene, having coincidentally scouted them in different locations without their knowledge. He said "all of us showed up to the first day of casting, like 'Hey...what are you doing here!'" However, Slash was the only one in the group to stay the entire 3 day shoot.