What is the setting of Naked Lunch by William S. Burroughs?

The novel takes place in a variety of location. The most important location is not really a physical place, but the mind of the narrator. Since so much of the plot is confusing in terms of location and action, it is very likely that much of it is actually a hallucination inside the mind of the narrator, who is a drug addict. This contributes to the sense of ambiguity throughout the novel in which the reader is unsure if events are really happening or not.