June 17, 2025
Trevor Hughes/USA TODAY NETWORK
Psilocybin is a psychedelic compound found in certain mushrooms. A new study shows that it helps reduce depression in cancer patients.
A single dose of psilocybin significantly decreased depression and anxiety in people with cancer, according to a new study.
Psilocybin is a chemical in certain mushrooms that causes hallucinogenic effects, such as an altered sense of time and space, distorted sights and sounds, and intense emotions. A previous study found psilocybin-assisted psychotherapy had potential for reducing psychiatric distress in people with life-threatening cancer, but concluded that more research was needed.
The new study, published Monday, found cancer patients who took a lone 25 mg dose of psilocybin under the guidance of a therapist experienced "robust" reductions in depression and anxiety – even two years later.
Between 15% and 25% of people with cancer have depression severe enough that it affects the ability to function, including going through treatment, according to the Fred Hutch Cancer Center in Seattle. Cancer patients sometimes experience what is termed "existential distress," characterized by feelings of hopelessness, lack of meaning and anxiety about death.
Of the 28 people in the new study, about half had substantial and sustained reductions in depression two years later. A quarter did not need any further psychedelic or antidepressant treatment. More than 40% also had long-term relief from anxiety.
The results "suggest a potentially paradigm-changing alternative to traditional antidepressants," according to the researchers.
Further study is needed to find out if repeat doses of psilocybin put people into full remission from cancer-related depression, the researchers wrote.
If future research produces similar results, "this could lead to greater use of psilocybin to treat depression in patients with cancer," said Dr. Manish Agrawal, the lead study author and CDO of Sunstone Therapies in Rockville, Maryland.
