TUESDAY, Jan. 28, 2020 (HealthDay News) -- A single dose of the psychedelic ingredient in "magic mushrooms" may bring long-lasting relief to cancer patients who suffer anxiety and depression, a new, small study suggests.
Researchers found that of 15 patients who'd received a one-time treatment with psilocybin, most were still showing "clinically significant" improvements in anxiety and depression four years later.
The study, published Jan. 28 in the Journal of Psychopharmacology, is a follow-up to one reported in 2016. That trial involved 29 cancer patients with psychiatric distress who received a single dose of psilocybin. Most responded quickly, with effects that lasted up to six months.
These latest findings suggest there can be ongoing benefits from what many study patients described as a "life-changing experience," the researchers said.
"It can come off as sounding like voodoo," said lead researcher Dr. Stephen Ross, an associate professor of psychiatry at NYU Langone Health, in New York City.
And, the truth is, no one is sure exactly how psilocybin works to lift entrenched anxiety and depression -- including the kind of "existential distress" that can plague people with a life-threatening disease.
Magic mushrooms have long been used recreationally for their hallucinogenic effects -- meaning they alter users' perceptions of their surroundings, and their own thoughts and feelings. That could end badly -- if people mistakenly think they can fly, for instance.
But given in a controlled medical setting, Ross said, psilocybin may help people with psychological distress "get out of that scared, stuck place."
It's not that the drug is "magic" or a "cure," he stressed. For one, not everyone benefits. Plus, the patients in this study also received psychotherapy.
"I don't think you can just give psilocybin alone," Ross said. "We definitely see this as psilocybin-assisted therapy."
And it's a therapy you cannot yet find at your local doctor's office. Psilocybin is illegal in the United States, and researchers need permission to use it in studies.
But a growing number of institutions are doing just that. NYU, Johns Hopkins, the University of California and other universities are currently studying psilocybin-assisted therapy for conditions such as eating disorders, addiction and major depression.
Medical research into psychedelics like psilocybin and LSD began in the 1950s, and then famously ended after a surge in recreational use by the 1960s "counterculture."
"Research stopped because of the sociopolitical context and street use -- not because the science wasn't there," said Matthew Johnson, associate director of the university's Center for Psychedelic and Consciousness Research.
He stressed that no one is suggesting people self-treat their mental health symptoms with mushrooms. "With recreational use, there's the risk of engaging in dangerous behavior," Johnson said.
"In the research setting, we're not only minimizing the risks, but also trying to maximize the benefits," he explained.
"I wouldn't expect these positive results from people using psilocybin on their own," Johnson said.
As for the mechanisms behind psilocybin, research points to a correlation between patients' perceptions of "mystical experiences" while on the drug and their symptom improvement. Those experiences, Johnson explained, can refer to a feeling of transcending the ego or, for the religiously inclined, feeling closer to God.
The experience seems to, in essence, allow some people "to do their own self-analysis," Johnson said.
What about effects on the brain? There is evidence, according to Ross and his colleagues, that psilocybin alters activity in the brain's default mode network, which turns on when we engage in self-reflection. But in people with depression or anxiety, that same network can be hyperactive and associated with worry and ruminating.
More research is needed to understand what's happening in the brain, Johnson said. Even more importantly, results from larger, rigorous studies are necessary to prove psilocybin is effective as medicine.
A limitation of the current study, Ross said, is that all patients eventually received psilocybin, so there was no true "control" group.
And patients in the follow-up study were people who were still alive several years after a cancer diagnosis, most of whom were in full or partial remission. It's always possible, Ross said, that they would be feeling good even if they'd never received psilocybin.
He noted, however, that cancer survivors frequently suffer from lingering anxiety and fear. But of the 15 patients in this study, 60% to 80% were meeting the criteria for a "clinically meaningful" improvement in their anxiety or depression four years out.
And nearly all, Ross said, still described their psilocybin experience as one of the most personally or spiritually meaningful ones of their lives.
The American Cancer Society has more on managing distress.