The hallucinogenic substance found in magic mushrooms could help smokers kick the habit, according to a pilot study published this week in the Journal of Psychopharmacology.

“This is the first study to provide preliminary data on the safety and feasibility of psilocybin as an adjunct to smoking cessation treatment,” Matthew W. Johnson of Johns Hopkins University School of Medicine and his colleagues wrote in their study.

“An estimated 5 million worldwide deaths per year are caused by tobacco use, and those numbers are projected to rise to over 8 million deaths annually by 2030. Given the global scope of smoking-related mortality, and the modest success rates of approved smoking cessation treatments, the novel approach presented here warrants further investigation with a randomized controlled trial.”

Due to the small size of the study, the researchers cannot make any definite medical recommendations.

But the findings — if they are supported by additional research — suggest psilocybin could be one of the most powerful anti-addiction treatments around. Most tobacco addiction treatments have a success rate of about 35 percent on average, while the psilocybin treatment had a success rate of 80 percent.

Psilocybin-containing mushrooms were outlawed in the United States in 1968 after the drug became associated with the hippie counterculture. Recent studies have found that the drug activates the brain network associated with dreaming, and a single dose can produce long-lasting changes in personality.

The researchers recruited 10 men and 5 women who smoked a minimum of 10 cigarettes per day and had multiple unsuccessful past attempts to quit smoking.

The participants attended four weekly meetings to receive cognitive behavioral therapy for smoking cessation. At these initial meetings, the researchers also prepared the participants for their psychedelic experience.

At week 5 of treatment, the participants were given a moderate dose of psilocybin. During this session, the participants were encouraged to lie down on a couch and focus on their thought processes, while wearing an eye mask and listening to music. The participants were closely monitored by two members of the research team.

Though the psilocybin has very few physiological side-effects and is not addictive, the drug can produce frightening or discomforting psychological experiences. One participant experienced an “extreme” rating of fear, fear of insanity, or feeling trapped at some time during a session, and another five participants reported “strong” ratings.

These experiences were “readily managed by interpersonal support, and had resolved by the end of the sessions,” the researchers said.

Once the experience came to an end, the participants were asked to write an open-ended narrative describing their session to discuss with staff the following day, the researchers explained.

The participants continued meeting weekly with the researchers, and received another dose of psilocybin at week 7. They were given the option to receive another dose at week 13. The treatment program ended after 15 weeks.

A six month follow-up found that 12 of the 15 participants had remained smoke-free.

Eleven of the participants had quit smoking after their first psilocybin session, “and demonstrated biologically verified smoking abstinence throughout the following 10 weeks of active treatment,” Johnson and his colleagues said.

In addition, 87 percent of the participants rated their psychedelic experience as among the 10 most meaningful experiences of their lives. The same percentage reported that their personal well-being or life satisfaction had increased very much as a result of their psilocybin sessions.

The study was the first to examine whether psilocybin could be useful in the treatment of tobacco addiction, though previous studies have found that another hallucinogenic drug, LSD, could help treat alcoholism, the researchers noted.

How these hallucinogenic drugs help fight addiction is unclear.

“Participant responses in the present study suggest that increased temporal horizon, increased self-efficacy, and altered life priorities may be involved,” Johnson and his colleagues wrote in their study. “The present results regarding tobacco addiction, combined with previous studies showing efficacy of 5-HT2AR agonists for treatment of alcoholism and opioid dependence, suggest higher-order psychological and/or biological mechanisms related to addiction are involved.”

“Quitting smoking isn’t a simple biological reaction to psilocybin, as with other medications that directly affect nicotine receptors,” Johnson further explained in a news release. “When administered after careful preparation and in a therapeutic context, psilocybin can lead to deep reflection about one’s life and spark motivation to change.”

The researchers’ next study will compare smoking success rates for people who take psilocybin versus those who use nicotine patches.