This was the first American film to be shot in Romania, particularly in the aftermath of the fall of Communism in Romania.
The Subspecies minions were originally going to be played by live actors in costume. Director Ted Nicolaou thought that the stuntmen were over-acting and that it didn't look well overall. Nicolaou then brought on FX artist David W. Allen to work with the subspecies stop-motion puppets.
Radu is named after Radu The Handsome, brother of Romanian prince Vlad The Impaler, who himself was the inspiration for the quintessential vampire Count Dracula.
Elements of the film, particularly the Subspeices minions, are actually recycled from an unmade film called "The Subterraneans", which in turn, was originally to have been filmed in the 1980s by producer Charles Band's previous studio, Empire International, in Rome.
Another deleted scene from the film featured Radu turning into a rotted corpse while asleep during the day. The director had the scene removed after realizing the effects didn't look very good.