On the DVD commentary, Dee Snider mentioned that filming the scenes with Carleton Hendricks rehabilitated and wearing a cardigan were the hardest parts of the movie to shoot. Snider hated wearing the cardigan.
After Captain Howdy was captured, and you see the newspaper clippings of the case, Dee Snider wrote all of the clippings as spoken in the commentary track. His reason is "for all you DVD nuts out there who'd pause and read them for continuity."
Captain Howdy is the name of the entity Regan talks to through a ouija board in The Exorcist (1973).
When the mob gathers around Carleton Hendricks' house, someone is holding a sign that says "We're not gonna take it". This is also the title of the biggest single from Dee Snider's band Twisted Sister.
Based loosely on the Twisted Sister song "Horror-Teria" from their album "Stay Hungry" (1984).