Zarkov is part of a pair of writers Gracie and Zarkov who write for Mondo 2000 magazine. Their book Notes From Underground: A Gracie and Zarkov Reader is considered a major personal reference book for psychedelic drugs.
In Douglas Rushkoff's book Cyberia, Zarkov says, in his discussion of Terence McKenna's views on drugs, "A drug is a tool, like a microscope, a telescope, or a radio. Is it some godlike metaphysical entity? Where I part company with Terence is where he talks about the drug as a metaphysical entity which looks, smells, tastes, and acts like God. I don't believe in God."