The way in which we commonly perceive so-called magic mushrooms—as the means to youthful psychedelic adventure—is undergoing a radical transformation. As Michael Pollan reports in this week’s issue of the magazine, doctors at major medical institutions have been using the hallucinogen psilocybin, the mushrooms’ active ingredient, to treat anxiety and “existential distress” in cancer patients. Eddie Marritz, a cinematographer and photographer in remission from small-cell carcinoma, participated in one of New York University’s research studies in late 2013, and continues to feel the benefits of the treatment. Marritz, who had gone into remission before deciding to enroll in the study, takes us through his trip.

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