As part of the film's promotion, the "Audrey II" plant was occasionally interviewed, in character, by the press. On at least one occasion, the interview concluded with Audrey II "eating" the interviewer.
Frank Oz originally wanted the Greek chorus (Crystal, Ronette and Chiffon) to be highlighted by a spotlight whenever they appeared, but this proved to be impractical as the light would spill over onto the other actors. He did manage to have them "magically" remain dry during the rainstorm in the title number.
Wardrobe and props were obtained from New York thrift shops in order to attain a period realism. The most difficult items to find were garbage cans, so set decorator Tessa Davies drove around in a truck filled with new cans, and whenever she saw an old one outside of someone's home, she stopped and offered to trade. "People thought I was crazy!" she remarked.
Bill Murray's scene in the waiting room was filmed as scripted, but there was virtually no written dialogue when his character got into the dentist's chair, except for ecstatic cries of pleasure. Over the course of the two days that he filmed, Murray kept riffing various ad-libs, which presented a challenge for the editor to assemble a coherent version of the scene.
The dentist's office originally was more grungy and blood-splattered but those details did not go over well with test audiences. The set was cleaned up and the scenes re-shot for the final film.