The Johns Hopkins University Psilocybin Smoking-Cessation Pilot Study was a small, open-label trial that paired cognitive behavioral therapy with psilocybin for smokers trying to quit. Its striking follow-up results suggested that a psychedelic experience might help some participants loosen the hold of a deeply established habit, while the study’s design left the findings preliminary rather than conclusive.

Background and Study Design

Matthew Johnson, a psychologist and protégé of Roland Griffiths at Johns Hopkins University, had worked on the laboratory’s early psilocybin studies, guiding several dozen sessions and helping analyze the data. In 2009, he launched the smoking-cessation study. His interest in psychedelics reached back to college, when he had read Ram Dass and learned about the Harvard Psilocybin Project; after arriving at Johns Hopkins for a pharmacology postdoctoral position in 2004, he discovered that Griffiths was quietly conducting a psilocybin project.

The pilot enrolled fifteen volunteer smokers who were trying to quit. They received several sessions of cognitive behavioral therapy followed by two or three psilocybin doses. The study was open-label: there was no placebo, and participants knew they were receiving the drug. Before a session, each volunteer had to stop smoking. Researchers measured carbon-monoxide levels at several intervals to check compliance and confirm continued abstinence.

Results and Limits

The results were notable against the difficulty of quitting smoking. Six months after the psychedelic sessions, 80 percent of participants had been confirmed abstinent. At one year, the figure was 67 percent, still higher than the success rate of the best treatment then available, as the book describes it. A larger randomized study comparing psilocybin therapy with the nicotine patch was under way at the time.

Those figures came from a tiny, nonrandomized study without a placebo group. They therefore offered an encouraging signal, not a definitive demonstration that psilocybin caused the quit rates. The researchers also found that participants who reported the most complete mystical experiences had the best outcomes. That association, like the overall results, pointed toward a possible relationship between the character of the experience and smoking cessation without establishing what produced the difference.

Charles Bessant and the Meaning of Quitting

Charles Bessant, one of the pilot’s participants, had remained abstinent for six years when the author spoke with him. He described the change in unusually plain terms: “Smoking became irrelevant, so I stopped.” The account contrasts with the effortful language often used to describe resisting an addiction. For Bessant, smoking had lost its importance; the significance of the experience lay in that shift in perspective, not merely in a stated resolve to abstain.

The author places such accounts alongside reports from other volunteers who felt able to see their lives from a new distance. In that framing, the study’s interest extends beyond whether participants experienced vivid journeys: it asks whether a changed sense of scale or priority can make a habit seem less compelling. The pilot’s small size and design cannot settle that question, but its results, Bessant’s sustained abstinence, and the association between more complete mystical experiences and better outcomes together helped motivate further investigation.