Rick Baker was originally doing the special effects for this movie, but he left to do An American Werewolf in London (1981), leaving the effects job for this movie in the hands of assistant Rob Bottin. Both this movie and "American Werewolf" were released the same year and both received praise for their makeup work.
There were times during shooting when Robert Picardo was very despondent about the hours he had to spend in makeup. On the Special Edition DVD, he remarked, "One day, after spending six and a half hours in the makeup chair, I was thinking, 'Trained at Yale, two leading roles on Broadway. My first acting role in California, my face gets melted in a low-budget horror movie.' All the crew had to say to that was, 'Bob, next time read the script all the way through first!"'
In the scene where Terri calls Chris from Dr. Waggner's office, a picture of Lon Chaney Jr. is seen on the office wall. Chaney played the Wolf Man in a series of five films (The Wolf Man (1941), Frankenstein Meets the Wolf Man (1943), House of Frankenstein (1944), House of Dracula (1945) and Abbott and Costello Meet Frankenstein (1948). He was the only actor that played a Universal Classic Monster in the original film and all of its sequels.
The final transformation had to be done all in close-up because this movie had exceeded its budget by then, and this had to be shot in Joe Dante's office because they had no money for sets anymore.
The following characters are named after werewolf movie directors: George Waggner, Roy William Neill, Terence Fisher, Freddie Francis, Erle C. Kenton, Sam Newfield, Charles Barton, Jerry Warren, Lew Landers and Jacinto Molina (an alternate name used by Paul Naschy).
Roger Corman: Uncredited, the famed B-movie producer, who had mentored the movie's director Joe Dante, as a man waiting to use a phone box after Karen White (Dee Wallace). When Corman checks the pay-phone for change, this is an in-joke reference to the producer's legendary penny-pinching.
Forrest J. Ackerman: Uncredited, as a bookstore customer in the book shop carrying a copy of his magazine "Famous Monsters of Filmland".
Joe Dante: [Regular Cast] Dick Miller. Director Joe Dante frequently casts Dick Miller. Robert Picardo (Eddie Quist) and Dick Miller (Walter Paisley) also appeared in Explorers (1985), Innerspace (1987), The 'Burbs (1989), Gremlins 2: The New Batch (1990), Matinee (1993), The Second Civil War (1997) and Looney Tunes: Back in Action (2003), all directed by Joe Dante.