(Christoph Schmidt/EPA)

Most long-time, pack-a-day smokers who took part in a small study were able to quit smoking after six months, and researchers believe the hallucinogenic substance found in "magic mushrooms" could be the reason why.

The study of the 15 participants, published this week in the Journal of Psychopharmacology, is the first to look at the feasibility of using the psychedelic drug psilocybin to aid in a smoking cessation treatment program.

Existing treatments, from quitting cold turkey to prescription medications like Varenicline (Chantix), work for some people, but not the majority of smokers. With Varenicline, which mimics the effect of nicotine in the body, only about 35 percent of participants in a clinical trial were still abstaining from smoking six months later.

Nearly half of all adult smokers reported that they tried to quit in 2010, according to the Centers for Disease Control and Prevention, yet 480,000 deaths are attributed to the addiction every year.

Researchers at Johns Hopkins University recruited a group of long-time, heavy smokers — an average of 19 cigarettes a day for an average of 31 years — to participate in the study.

They were treated with cognitive behavioral therapy for 15 weeks, and they were given a dose of the hallucinogen psilocybin at the five-week mark, when they had agreed to stop smoking.

Although it was a small study, the results were promising. Twelve of the participants had quit smoking six months after being treated with the drug.

The findings, though not conclusive, suggests that further research should be pursued to find out whether the results can be replicated on a larger scale, and perhaps more importantly, what happens in the brains of addicts when they are treated with the drug.

For now, however, little is known about how the psychological experience affected their ability to give up cigarettes.

But researchers do know that while the drug is active in their systems, it is a disconcerting and sometimes deeply uncomfortable experience.

For five or six hours, the drug causes feelings of anxiety, of being near death, and intense hallucinations. While on the drug, the subjects might feel like they’re losing their minds, or like they're spiraling out of control. Feelings of panic and fear are also common.

Otherwise, the drug is considered to be, relatively speaking, medically safe, said Matthew W. Johnson, an associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and the study’s lead author.

"The drug is actually very safe at the physiological level," Johnson said in an interview.

Through it all, they were aided by clinical volunteers who helped manage the anxiety and a medical doctor was on hand to handle any health problems that might have arisen.

The participants were given the drug in a “living room-like” environment, and were instructed to lie on a couch with eye shades while soothing music played. Eventually, the drug would wear off, and more traditional therapy continued for several more weeks. Two other stronger doses of the drug were administered during that time.

According to Johnson, participants came away from the "trip" feeling profoundly changed. They can feel more capable of accomplishing things, more open to different viewpoints than the ones they previously held, and some even reported fewer feelings of nicotine withdrawal (though most reported cravings of some kind).

"That kind of personality openness is consistent with addiction recovery,” Johnson said. “They have these 'aha' moments where they believe 'wow, I can do this.' "

There are causes for concern, however. The use of hallucinogenic drugs like psilocybin and its related drug LSD in treating addiction has been hampered for decades by concerns over safety, efficacy and medical ethics.

Psilocybin, in particular, is not addictive, but it is abused. The disorienting experience  can send people who take it into a state of panic and it can exacerbate psychological conditions like schizophrenia.

In this study, the drug raised participants' blood pressure and heart rates. And two participants declined to participate in a third session with the drug, according to Johnson, saying  they felt that they had already experienced whatever benefits they could get from it.

The use of magic mushrooms as a form of addiction treatment for smoking is a long way off, and indeed might never be used as a widespread treatment.

But for the participants of this study, all of whom had previously attempted to quit smoking multiple times, it was part of a comprehensive intervention that worked in most cases.

Some had tried to quit in the past for days, months or a year at a time, but they inevitably resumed their habit.

It is still unknown whether this successful result will hold, but Johnson and his team are poised to begin a randomized controlled trial that could produce more concrete conclusions.

Still, Johnson believes that the mind-altering properties of psilocybin played a substantial role in helping the study’s participants re-evaluate their potential, their lives and their choices. And those benefits, he said, could be applied to other addiction as well.

“This is really targeting, I believe, addiction,” Johnson said. “It’s exciting that this seems to be a novel model of effecting and understanding human behavioral change, beyond the particular behavior in question.”