By the time Jon Kostas was 25, he was desperate to beat his alcohol addiction. He had started drinking at age 13 and had cycled through different treatments—going to Alcoholics Anonymous meetings, taking pharmaceutical medications, and trying in-patient rehab—but nothing worked. Ever since 2015, however, when he took part in a clinical trial that combined talk therapy and psilocybin—the psychedelic active ingredient in magic mushrooms—Kostas has quit drinking. “I’m forever grateful and indebted,” he says. “This saved my life.”
A randomized clinical trial, published Aug. 24 in the journal JAMA Psychiatry, found that in combination with psychotherapy, psilocybin helped treat people’s alcohol use disorder. Analyzing a group of 93 patients with the condition—Kostas among them— for 32 weeks, researchers found that patients who had received psilocybin plus psychotherapy (48 in total) reduced their drinking by 83% within eight months of their first dose, compared to 51% among those who had received a placebo. Nearly half of people treated with psilocybin stopped drinking completely, compared to less than a quarter of those who’d only received the placebo.
“If these effects are replicated, I think this really would represent a breakthrough,” says Dr. Michael Bogenschutz, director of the New York University Langone Center for Psychedelic Medicine and the senior author of the study. “The effects seem to persist. And the effects are larger than those of any of the treatments that are currently available,” which includes methods like in-patient rehab, talk therapy, and medications.
A more effective treatment for alcohol addiction could have profound, society-wide effects. About 95,000 Americans die from alcohol-related causes each year, including alcoholic liver disease and car accidents, according to the U.S. Centers for Disease Control and Prevention. A 2021 federal analysis of Americans pre-pandemic found that while about 5% of U.S. adults—about 14.1 million people—had alcohol use disorder in the last year, only 7% of them received any treatment, and just under 3% were treated with medication. Even when people receive treatment, however, approved medications such as naltrexone have been shown to only have limited effectiveness.
The new research adds the strongest evidence yet that psilocybin may be a promising treatment for substance use disorders. Another preliminary study by Bogenschutz and other researchers in 2015 found that psilocybin-assisted therapy seemed to treat alcohol addiction in a small test group of patients. And a small study published in 2014 by Bogenschutz and some of the same researchers found that psilocybin combined with talk therapy can help people stop smoking. Last year, the team received the first federal grant for a psychedelic treatment in over 50 years to expand that research with a three-year, multisite study.
Psilocybin’s effectiveness may have to do with how it affects the brain, says Bogenschutz. Research suggests that psilocybin promotes neuroplasticity, which allows people to change the way they think and behave. Researchers have also found that psilocybin helps treat depression—which often occurs alongside substance use disorder. One of the things that makes psilocybin such a promising treatment, says Bogenschutz, is that unlike medications that must be taken over and over again, psilocybin has a long-lasting, powerful effect after just a few doses. “It really suggests that we’re treating the underlying disorder, rather than simply treating the symptoms,” says Bogenschutz.
While the results of this study are encouraging, there’s still a long way to go before psilocybin can be used to treat a wider population. Fewer than 50 patients received psilocybin during the clinical trial, which means more research must be conducted on a larger, diverse population. Plus, the placebo used in the trial, diphenhydramine—an antihistamine—isn’t a perfect substitute for psilocybin, as psychedelic drugs produce unique hallucinogenic effects. Bogenschutz adds that people shouldn’t experiment with psilocybin outside of clinical settings, because it may be more risky in an uncontrolled environment, in part because patients’ experiences can feel extreme. For instance, some patients feel severe anxiety while under the drug’s influence.
The study also didn’t include the full range of people who could benefit from psilocybin-assisted treatment. Bogenschutz noted that on average, participants tended to have less severe drinking intensity than people who typically join clinical trials for the condition. (According to Bogenschutz, that’s likely because the trial may have appealed to people who were already coping with their disorder.) The researchers also intentionally excluded patients with other mental health disorders, such as depression, to ensure they could determine whether psilocybin-assisted therapy treats alcohol addiction, and not some other underlying condition.
However, Bogenschutz says it’s possible that patients with more severe disease might benefit even more from the treatment, especially if psilocybin can address the problems that underlie not only alcohol use disorder, but also mental-health issues like depression and anxiety, and even other kinds of substance use disorders. “People with co-occurring disorders and addictions might be an ideal population for this kind of treatment, because they might be able to benefit simultaneously for both disorders,” he says. Their hope is that “this more flexible pattern of brain function allows people to change their thoughts and behaviors in ways that allow them to be happier, healthier, people.”
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