Additionally, nearly half of study participants treated with psilocybin stopped drinking entirely eight months after receiving their first dose of psilocybin, compared with nearly a quarter of those in the placebo group, per a press release from the NYU Grossman School of Medicine. “Today’s study that you’re hearing about is a major breakthrough in the understanding and treatment of alcohol use disorder,” said Charles Marmar, MD, the Lucius N. Littauer Professor of Psychiatry and the chair of the department of psychiatry at the NYU Grossman School of Medicine in New York City, at a virtual press conference about the findings held on August 24. Dr. Marmar did not contribute to the study. The new data is important because it has the potential to help a lot of people who are struggling, according to an editorial published alongside the study in JAMA Psychiatry. For starters, AUD — which affected 14.5 million Americans ages 12 or older in 2019, per the Centers for Disease Control and Prevention (CDC) — is underdiagnosed and undertreated. Of all people who’ve been diagnosed with AUD, only 4 percent receive a medication approved by the U.S. Food and Drug Administration (FDA). “[Psilocybin plus psychotherapy] is a very promising step toward a novel approach to treating alcohol use disorder in a group of moderate to heavy drinkers that do not have other major psychiatric issues,” says Rachel Yehuda, PhD, the director of the Center for Psychedelic Psychotherapy and Trauma Research at the Icahn School of Medicine at Mount Sinai in New York City, who was not affiliated with the study. Only three medications have been FDA-approved for AUD since 1949: disulfiram (Antabuse), naltrexone (ReVia, Vivitrol), and acamprosate (Campral). These drugs have limited effectiveness, which is why new drug treatments for AUD are needed, the editorial notes. “While we did not directly compare psilocybin to other active treatments in this study, the effects we observed were considerably larger than those of currently approved treatments for alcohol use disorder,” explained the psychiatrist Michael Bogenschutz, MD, the senior author of the study and the director of the NYU Langone Center for Psychedelic Medicine in New York City, during the press conference.

Psilocybin Led to a ‘Robust’ Decrease in Heavy Drinking Days

During the 12-week study, which included 95 participants with AUD between the ages of 25 and 65, researchers compared the effectiveness of up to 12 sessions of psychotherapy provided by a team of two mental health professionals, plus two daylong treatments with either psilocybin or an active placebo (diphenhydramine [Benadryl], an antihistamine) during weeks 4 and 8. Because the study was blinded, meaning the participants did not know during the study whether they were receiving psilocybin or placebo, both were administered as a single opaque oral capsule. During medication sessions, participants were supervised by a therapist in a treatment room for eight hours, and were encouraged to relax on a couch with eye shades and wear headphones playing a standardized music playlist. Forty-nine participants were randomly assigned to the psilocybin group, and 46 to the placebo group. Researchers followed up with the participants for 32 weeks to see how they fared after treatment. During that follow-up period, the percentage of heavy drinking days — defined as at least five drinks a day for men and four drinks a day for women — decreased to 9.7 percent of the time for the psilocybin group compared with 23.6 percent for the placebo group, an average difference of nearly 14 percent. The study also showed that psilocybin-treated participants on average consumed less alcohol each day than those who received placebo. No participants in the psilocybin group experienced any serious adverse events, meaning unexpected, life-threatening medical problems, from treatment. The most common side effects of psilocybin among participants were headaches, nausea, and anxiety, but it’s important to note that the study participants were carefully selected and did not have any other mental or physical health conditions that could be influenced by psilocybin. “[Psilocybin plus psychotherapy] definitely affected my life, and I’d say it saved my life,” said Jon Kostas, one of the first participants in the trial, who shared his experiences during the press conference. According to Kostas, by the time he learned of this trial at age 25, his AUD had been classified by his doctors as “treatment resistant.” He had previously tried getting help via Alcoholics Anonymous support groups, other drug treatments, and rehabilitation programs. “My greatest expectations for this [trial] were to be able to manage my cravings. This surpassed that. This eliminated my cravings to the point where it cured my alcoholism, and I don’t categorize myself as an alcoholic anymore,” Kostas said during the press conference. Paul Mavis, another participant in the trial, had similar experiences with the treatment. “I haven’t had a drink or even a craving or even a thought [since receiving treatment]. It’s weird — it’s as if I never drank in my life,” Mavis said during the press conference.

Psilocybin Works Differently Than Other FDA-Approved Treatments for AUD

Although the researchers don’t fully understand the mechanism by which psilocybin helps people with AUD, it’s known to bind to the serotonin 2A receptor, a part of the brain thought to be involved in certain mental health conditions, the researchers noted in the study. “It’s definitely a very different mechanism of action from any currently approved medication, and we really are just beginning to unpack what’s going on,” explained Dr. Bogenschutz during the press conference. There’s evidence, he added, that psilocybin affects neuroplasticity, meaning it enhances the brain’s capacity to change and adapt. “So, we can hypothesize that there’s an enhanced potential for change,” he said. And so the mechanism could be that it helps make the psychotherapy patients are doing more effective when it comes to behavior change. Importantly, psychotherapy appears to be a crucial component of psilocybin treatment. “One of the most interesting aspects of this work is, there appears to be a profound relationship between the action of psilocybin and the effectiveness of psychotherapy such that either by themselves might be significantly less effective,” said Marmar during the press conference. Future research is needed to know for sure, Bogenschutz and Marmar said.

Psilocybin Shows Promise for Depression, Too

These findings for AUD are both encouraging and “consistent with the results of multiple clinical trials of the drug for treating major depressive disorder [MDD],” according to the authors of the editorial. In one small trial of patients with MDD, published in November 2020 in JAMA Psychiatry, psilocybin when given with supportive therapy was found to significantly reduce depressive symptoms compared with no treatment, and more than half of participants achieved remission four weeks after treatment. Psilocybin appeared to be similarly effective to escitalopram (Lexapro), a commonly used FDA-approved antidepressant, when given alongside psychological support in a small trial including nearly 60 people with depression, published in April 2021 in the New England Journal of Medicine. It’s also shown effectiveness in alleviating symptoms of depression and anxiety and improving quality of life among patients with life-threatening cancer diagnoses, according to a small study published in December 2016 in the Journal of Psychopharmacology.

What’s Next for Psilocybin Treatment?

Although the findings are promising, psilocybin still faces a long path to FDA approval. Future and larger studies are still needed to confirm these findings and to determine appropriate dosages for use in clinical settings, according to the NYU press release. Bogenschutz and his team have plans to launch a larger, multicenter trial in 2023. This trial will take several years to complete, Bogenschutz said in the press conference. Additionally, it will be important to replicate these results in a more diverse group with greater minority representation, as well as the study of how psilocybin might affect alcohol use in populations who have anxiety, trauma, and depression, Dr. Yehuda says. Nearly 79 percent of the participants in the present study were non-Hispanic white. “The proof of concept here that drinking can be reduced by psilocybin plus psychotherapy now warrants future investigation for this approach,” she says. Psilocybin is currently illegal in the United States, and it’s not likely to be available to the public anytime soon. It’s classified as a Schedule 1 substance under the Controlled Substances Act, according to the U.S. Department of Justice (DOJ) and the Drug Enforcement Administration (DEA). This means that it’s currently considered to have a “high potential for abuse, no currently accepted medical use in treatment in the United States, and a lack of accepted safety for use under medical supervision,” even though the aforementioned scientific research has suggested otherwise. Scientists who wish to study the medicinal effects of Schedule 1 substances like psilocybin must get formal approval from the DEA before doing so.

Experts Warn, Don’t Try Psilocybin Research at Home

Experts caution that individuals shouldn’t try this treatment approach at home. “The important thing to point out with psychedelics is that intention and concomitant psychotherapy are key ingredients in the therapeutic effects of psychedelics,” Yehuda says. Using psilocybin recreationally is different, and there’s no evidence that using the drug alone will reduce a behavior that may be harmful, such as excessive drinking, she explains. “Taking psilocybin without the therapy may not have produced the same effects at all, and this is something that the public really needs to understand,” Yehuda adds. RELATED: Michael Pollan’s New Netflix Series Aims to Destigmatize Psychedelics: 8 Myths and Facts to Know