A single dose of psilocybin - the psychedelic compound in magic mushrooms - may reduce anxiety and depression in patients with advanced cancer, according to the results of two new studies.
Both studies - conducted by investigators from the NYU Langone Medical Center in New York, NY, and Johns Hopkins Medicine in Baltimore, MD - were recently published in the Journal of Psychopharmacology.
Psilocybin is a substance present in various mushrooms - often called magic mushrooms or "shrooms" - found in Europe, South America, and the United States.
Psilocybin is a Schedule I substance under America's Controlled Substances Act, which means it is deemed as having "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."
The new study, however, suggests there may be a medical use for psilocybin after all; it could help alleviate cancer-related psychological distress.
Cancer, anxiety, and depression
While cancer mortality has improved significantly in recent decades, almost 600,000 Americans are expected to die from the disease this year. This outcome is more likely for patients whose cancer has become advanced - that is, it has spread to other areas of the body or is no longer responding to treatment.
Unsurprisingly, feelings of anxiety and depression are widespread among patients with cancer; the National Cancer Institute report that around 15-25 percent of individuals experience depression after a cancer diagnosis.
"A life-threatening cancer diagnosis can be psychologically challenging, with anxiety and depression as very common symptoms," says Roland Griffiths, Ph.D., co-author of the Johns Hopkins study and professor of behavioral biology in the Departments of Psychiatry and Behavioral Sciences and Neuroscience at Johns Hopkins.
"People with this kind of existential anxiety often feel hopeless and are worried about the meaning of life and what happens upon death," he adds.
Previous research has suggested that psilocybin may be effective in alleviating symptoms of anxiety and depression. With this in mind, the two research teams set out to investigate whether the substance might be helpful for patients with cancer-related anxiety and depression.
Psilocybin's psychological benefits lasted for 6 months
For the first study, Griffiths and team enrolled 51 adults of an average age of 56 who had been diagnosed with life-threatening cancers, the majority of which were breast, upper digestive tract, gastrointestinal tract, genitourinary, or blood cancers.
- In 2012, around 14 million new cancer cases were diagnosed across the globe
- Around 39.6 percent of men and women in the U.S. will be diagnosed with cancer at some point in their lives
- By 2020, the national cost of cancer care in the U.S. could reach $156 billion, compared with almost $125 billion in 2010.
Most of the cancers were recurrent or metastatic, the team reports, and 92 percent of subjects were white.
Each patient took part in two treatment sessions. In the first session, patients received a low, "control" dose of psilocybin (1 or 3 milligrams per 70 kilograms) in the form of the capsule. In the second session, which took place 5 weeks later, patients received a moderate or high dose of the compound (22 or 30 milligrams per 70 kilograms).
The researchers assessed patients' mood, behaviors, symptoms of anxiety and depression, attitude toward life, and spirituality before the first treatment session, 7 hours after using psilocybin, 5 weeks after each treatment session, and 6 months after the second treatment session.
Anxiety and depression were monitored using tools such as the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, and the Beck Depression Inventory.
The researchers found that patients showed immediate reduction in symptoms of anxiety and depression after being treated with moderate or high doses of psilocybin.
What is more, the effects of psilocybin persisted; around 80 percent of patients showed clinically significant reductions in anxiety and depression at 6 months after the final treatment session.
Additionally, the compound was found to increase well-being and life satisfaction for around 67 percent of patients.
"The most interesting and remarkable finding is that a single dose of psilocybin, which lasts 4 to 6 hours, produced enduring decreases in depression and anxiety symptoms, and this may represent a fascinating new model for treating some psychiatric conditions."
Roland Griffiths, Ph.D.
'Strongest evidence to date for benefits of psilocybin therapy'
The second study provides further evidence of the possible psychological benefits of psilocybin.
Led by Dr. Stephen Ross, of the Department of Psychiatry at NYU Langone, the research involved 29 adults aged 22-75 who had been diagnosed with either advanced breast, gastrointestinal, or blood cancers.
Most of the patients were female, and all subjects had been diagnosed with severe, cancer-related psychological distress.
Participants were allocated to one of two treatment groups. One group received psilocybin (a dose of 0.3 milligrams per kilogram) and the other group received a placebo in the form of 250 milligrams of niacin - a vitamin that is known to simulate drug-induced hallucinations.
After 7 weeks, patients in each group switched treatments, and they were monitored for a further 7 weeks. The study was double-blind, meaning the patients and the researchers were unaware of which treatments they were receiving.
Both treatment groups received counseling throughout the duration of the study, and all patients were clinically assessed for symptoms of anxiety and depression for up to 8 months after treatment ceased.
The researchers found that treatment with psilocybin quickly led to improvements in anxiety and depression for the patients, and similar to the results of the Johns Hopkins study, around 80 percent of patients reported improvements at 6-8 months after treatment stopped.
"Our results represent the strongest evidence to date of a clinical benefit from psilocybin therapy, with the potential to transform care for patients with cancer-related psychological distress.
If larger clinical trials prove successful, then we could ultimately have available a safe, effective, and inexpensive medication - dispensed under strict control - to alleviate the distress that increases suicide rates among cancer patients."
Dr. Stephen Ross
How might psilocybin improve psychological distress?
Dr. Ross and colleagues note that the mechanisms behind psilocybin's pestilential psychological benefits are unclear, but they point to studies suggesting that the compound activates some brain regions targeted by serotonin - a neurotransmitter related to mood.
Further studies are needed to uncover the precise mechanisms by which psilocybin might affect anxiety and depression.
Overall, both research teams believe their results indicate that psilocybin may be an effective psychological therapy, not just for cancer patients, but for patients with other illnesses that cause distress.
"Our study showed that psilocybin facilitated experiences that drove reductions in psychological distress," says Anthony Bossis, Ph.D., co-author of the NYU Langone study. "And if it's true for cancer care, then it could apply to other stressful medical conditions."
The researchers stress that patients should not use psilocybin without supervision from a doctor and a trained counselor.
"Psilocybin therapy may not work for everyone, and some groups, such as people with schizophrenia, as well as adolescents, should not be treated with it," says Bossis.
As well as hallucinations, psilocybin can cause a number of physical side effects, including nausea, vomiting, and increased blood pressure.