Psilocybin shows potential for treating mental health disorders in people with cancer and addiction

One or two doses of psilocybin, a compound found in psychedelic mushrooms, may improve the mental health of cancer patients when accompanied by psychotherapy, a new report suggests. A second new study found that treatment with psilocybin resulted in lasting, positive personality changes in patients with alcohol use disorder.

The first report's findings were published online Oct. 7 in the journal Nature Mental Health, and the second published online Jan. 1 in a special edition of The American Journal of Psychiatry focused on psilocybin research.

In the first study, a team of experts at NYU Langone Health found that psilocybin accompanied by psychotherapy significantly reduced anxiety, depression, obsessive thoughts, anger toward others, and physical symptoms associated with psychological distress, with improvements lasting up to six months.

Our findings suggest that the mental health benefits of psilocybin therapy for cancer patients may reach far beyond what we have previously understood."

Petros Petridis, MD, study lead author, clinical assistant professor, Department of Psychiatry at NYU Grossman School of Medicine

The study also concluded that the mood-altering psilocybin did not appear to cause any lasting paranoia, psychosis, or deep feelings of fear (phobia). As a result, their analysis adds to the mounting body of evidence that psilocybin can be safely administered under close medical supervision, says study senior author Stephen Ross, MD. Ross is a clinical professor in the Departments of Psychiatry, and Child and Adolescent Psychiatry at NYU Grossman School of Medicine and serves as an associate director of its Center for Psychedelic Medicine.

For the study, the researchers analyzed data from two previous clinical trials that used psilocybin-assisted psychotherapy to address anxiety and depression in 79 men and women with cancer. In the trials, about half of the participants initially received a large dose of psilocybin while the rest were given either vitamin B3 or a tiny dose of the psychedelic drug as a placebo. Neither the researchers nor the patients were told which medication they were given.

After six or seven weeks, depending on the trial, the groups switched treatments. Psychotherapy preceded and followed each dosing session, and the participants completed a questionnaire about mental health symptoms at the beginning of the study and six months after the second dosing.

In the second new study, another team, led by researchers at NYU Grossman School of Medicine, found that psilocybin therapy may also improve mental health for those with alcohol use disorder. Compared to patients receiving a placebo, those treated with psilocybin were found to be significantly less impulsive, depressed, and vulnerable than they were prior to the therapy. At the same time, these patients grew more "open," or more accepting of their thoughts and emotions. These changes were observed seven months after the participants received their second dose of psilocybin.

This analysis examined personality changes in men and women participating in a previous clinical trial that used psilocybin-assisted psychotherapy to treat alcohol dependence. During the trial, participants randomly received two doses of either psilocybin or an antihistamine placebo, receiving psychotherapy before and after each dosing session. The authors tested 83 of the patients using a standard personality assessment before psychotherapy began and again eight months after the first dose of study medication.

"Since impulsiveness has long been linked to both excessive drinking and relapse after treatment, the personality changes brought about by psilocybin-assisted psychotherapy may help those recovering from alcohol dependence remain resilient to internal and external stressors known to trigger relapse," said study lead author Broc Pagni, PhD. Pagni is a postdoctoral fellow in the Department of Psychiatry at NYU Grossman School of Medicine.

Notably, the findings also showed that men were more likely to experience a boost of positive emotions while women were more likely to see an increase in openness. However, further research is needed to understand the reasons behind these differences or what they might mean for any given patient, says study senior author Michael Bogenschutz, MD.

Bogenschutz, a professor in the Department of Psychiatry at NYU Grossman School of Medicine and the director of its Center for Psychedelic Medicine, adds that the study authors next plan to explore whether the personality changes observed in the current investigation may also occur in psilocybin trials for opioid-use disorder.

Bogenschutz cautions that in both studies, most participants were able to correctly guess whether they had received psilocybin or a placebo.

Psilocybin is a naturally occurring compound derived from fungi with mind-altering qualities similar to those of LSD and mescaline. Most study participants experience profound alterations in perception, emotions, and sense of self, often including experiences that are felt to be of great personal and spiritual significance. Because the drug raises blood pressure and heart rate and can cause incapacitating and sometimes overwhelming psychological effects, researchers caution that it should only be used in controlled settings and in conjunction with medical and psychological evaluation and careful preparation.

Funding for the study in Nature Mental Health was provided by National Institutes of Health grants UL1TR000038 and T32DA007250. Further funding support was provided by the Heffter Research Institute, the RiverStyx Foundation, the Betsy Gordon Foundation, the Fetzer Institute, the Usona Institute, the Canadian Institutes of Health Research, Carey and Claudia Turnbull, W. Linton, R. Barnhart, A. Altschul, K. Fitzsimmons, the McCormick Family, G. Goldsmith, and E. Malievskaia. Funding for the study in The American Journal of Psychiatry was provided by the Heffter Research Institute and individual donations from Carey and Claudia Turnbull, Dr. Efrem Nulman, Rodrigo Niño, and Cody Swift.

In addition to Petridis, Ross, Pagni, and Bogenschutz, other NYU Langone researchers involved in the studies are Richard Zeifman, PhD; Brennan Carrithers, MD; Noam Goldway, PhD; and Kelley O'Donnell, MD, PhD. Other coinvestigators include Jack Grinband, PhD, and Connor Kinslow, MD, at Columbia University in New York City; Gabrielle Agin-Liebes, PhD, at Yale University in New Haven, Conn.; Roland Griffiths, PhD, at Johns Hopkins University in Baltimore, Md.; Sarah Mennenga, PhD, at Arizona State University in Tempe, Ariz.; and Snehal Bhatt, MD, at the University of New Mexico in Albuquerque, N.M.