Trivia: Makeup artist Rick Baker wanted the werewolf to be bipedal. Director John Landis refused, insisting it had to be a four-legged hound from hell.
Trivia: John Landis wanted to use Cat Stevens song Moon Shadow for the opening credits. Cat Stevens refused because he believes werewolves actually exist.
Trivia: Rick Baker promised John Landis that he would work with him on An American Werewolf in London when John had enough money to make it. After waiting eight years, Rick decided to work on The Howling, another werewolf themed movie. One day, right out of the blue, John called Rick and told him he had finally had the money to make American Werewolf. According to Rick, when he informed John that he was already working on another werewolf movie, John started screaming and swearing at Rick. Rick calmed John down and told him he would still do American Werewolf and leave the werewolves for The Howling to Rob Bottin. Rick has stated that to this day, John has still not forgiven him for working on another werewolf movie.
Trivia: When Jack first appears to David in the hospital as a corpse, Jack takes a piece of toast and eats it. Originally, the toast was supposed to fall out of a hole in Jack's throat but the censors found it too disturbing.
Trivia: In nearly every John Landis film, you can see or hear the phrase "See you next Wednesday." In this film, it's an adult film.
Trivia: When David is in Piccadilly Circus calling home, he speaks to his sister Rachel and asks where Max is. Rachel and Max are the names of director John Landis' children.
Trivia: When David is at the phone booth, he talks with his sister Rachel. He then asks her about his brother Max. Rachel and Max are the names of director John Landis' children.
Trivia: Near the end of the movie when David as a werewolf terrorizes Piccadilly Circus, there is a scene of a man standing in front of a store who is then being knocked backwards and falling through the glass. This is the director himself, John Landis.
Trivia: John Landis got the idea for the film while working on Kelly's Heroes (1970) as a production assistant in Yugoslavia. While watching a gypsy funeral (where they lace the coffin with garlic so the corpse doesn't come back to haunt everyone) he wondered how a western culture would react to being visited by a dead friend.
Trivia: Only four American work permits were requested of the British government for the production: for director John Landis, makeup artist Rick Baker, and actors David Naughton and Griffin Dunne. The first three work permits were granted by the British government without question. But the British office of Actors' Equity questioned the necessity of a work permit for actor Dunne, claiming that there were already plenty of young American actors living in Great Britain who could portray the role of Jack. It was only when director/screenwriter Landis threatened to rewrite the script and re-title the movie "An American Werewolf in Paris" that the equity office reconsidered the application and granted Dunne his work permit.