[MunchkinMan]

Actually, the rules go further, and say that Throwable Items can only be used in your current room or an adjacent one. Monster Enhancers are not Throwable Items. Neither are Scrolls, so you can use those from anywhere (unless, of course, a specific card says otherwise). It's not about one-shot Items, or one-shot cards, but about specifically defined things, and Munchkin Quest goes very far to define things very carefully. It even has a glossary that is, in my opinion, required reading.