Written by Dr. Samuel Douglas
Edited by Tara Ruttenberg and the Mushroom Tao team
There has been an explosion of research on psilocybin in recent years. The articles cited below represent only a small fraction of the scientific literature on the subject. Science has shown psilocybin to be effective in enhancing the lives of people who are experiencing difficult-to-treat conditions, as well as those who have no serious health issues.
Existing therapies, such as cognitive-behavioral therapy and antidepressants such as selective serotonin reuptake inhibitors (SSRIs), often fail to alleviate symptoms for many people suffering from depression.
First, a few words on modern antidepressants (and also related classes of medications such as antipsychotics and benzodiazepines).
Modern antidepressant drugs were designed to help individuals cope and “keep going” by numbing emotions, not to treat root causes of mental and emotional health conditions. These medications can be helpful for a time, but often after sustained use, the positive effects diminish. Without having prioritized the development of natural, healthy coping mechanisms, individuals are often left with a dangerous dependence on chemicals to suppress overwhelming emotions.
These medications are akin to bandaids over infected wounds -- they can help people pretend the infections have disappeared and can act as a short-term solution to keep the wound clean until more effective care is arranged. But bandaids do not heal the wound; unprocessed emotions buried by these medications lead to various diseases of the body and mind.
Fortunately, mounting evidence points to the effectiveness of psilocybin to address the root causes of treatment-resistant depression. Given that hundreds of millions of people worldwide suffer from chronic depression, the helpful benefits of psilocybin have broad potential worth exploring in greater depth.
Much of the evidence for psilocybin’s helpful effects on depression is found in recent research led by Robin Carhart-Harris. In his 2016 open-label study, he found that two moderate to high doses of psilocybin, given in a supportive environment seven days apart, significantly reduced symptoms of depression. This effect was so strong that almost 60% of participants no longer met the criteria for being clinically depressed at the three-month follow-up. His open-label trial in 2017 showed similar results that persisted for up to 6 months after the psilocybin sessions. And his 2021 double-blind, randomized controlled trial showed that two doses of psilocybin were at least as effective as six weeks’ use of a conventional antidepressant.
Psilocybin also seems to produce beneficial changes in how people think. Research led by Rosalind Watts showed that after two psilocybin experiences, people suffering from treatment-resistant depression felt more connected with other people. They were also less likely to avoid thinking about or dealing with difficult emotions or thoughts.
While scientists have conducted most of this research under strict clinical conditions, the benefits are not limited to these settings. Richard Ziefman and his team surveyed people before and after using psychedelics (including psilocybin) in non-clinical settings, such as in their homes and at guided psychedelic retreats. Most survey participants had lower depression severity than before, at rates similar to trials operating with stricter clinical protocols.
The current pandemic and the growing collective awareness about climate change and its impact on human civilization have given people the opportunity to contemplate their own fragility and mortality. Acknowledging life’s impermanence and peacefully facing death can be difficult for many of us.
This is especially true for people battling cancer and other serious illnesses. The existential distress related to these illnesses can include depression, anxiety, and deep fears about the well-being of those left behind. Unsurprisingly, end-of-life distress is nearly impossible to alleviate with current treatment options. Research suggests psilocybin may be a helpful alternative.
Roland Griffiths and Matthew Johnson found that a single psilocybin experience produced multiple benefits for people who have life-threatening cancer. Participants’ depression and anxiety symptoms improved. Their quality of life was better. They were more optimistic and felt that life had more meaning. At the six-month follow-up, 80% of participants were still enjoying these shifts in perspective.
Other research teams, led by Stephen Ross and Gabrielle Agin-Liebes, have independently achieved similar results. Around 80% of participants in both studies experienced significantly improved anxiety and depression symptoms for up to six months after a single psilocybin experience.
Helping people deal with and move through the end of their lives is a crucial area in psilocybin research, with ongoing trials being run in the US, UK, and Australia. Therapsil, a Canadian nonprofit, is at the forefront of the movement to allow end-of-life patients to use psilocybin. A Seattle-based clinic, Advanced Integrative Medical Science (AIMS) Institute, is suing the DEA for the right to administer psilocybin to dying patients under right-to-try laws. The core question remains: if people are not even free to choose the way they die, are they actually free to choose the way they live?
Based on some of this research, one may assume that psilocybin can only benefit people with serious psychological illnesses or challenges. But this is not the case. Positive psychological effects as a result of psilocybin experiences have been consistently reported in research participants with no known health conditions.
Studerus, Kometer, Hasler & Vollenweider (2011) looked at eight double-blind placebo-controlled psilocybin trials conducted on healthy individuals between 1999 and 2008. They found that most participants described the experience as “pleasurable, enriching and non-threatening.”
Roland Griffiths and his team observed similar results in their 2011 study. Healthy volunteers described high-dose psilocybin experiences as being highly personal and spiritually significant. They found that their mood, attitudes, and behavior all improved. Many participants reported better relationships with family and others. They took better care of themselves physically, emotionally, and spiritually. When Griffiths followed up with these people over a year later, these improvements had persisted.
When scientists look at the results of large-scale surveys and population data on psychedelic use, interesting trends emerge. For example, Thiessen, Walsh, Bird, & Lafrance (2018) found that men who reported any LSD or psilocybin use were 50% less likely to have committed violence against their partners. The researchers suggest this could be because psychedelic use can improve emotional regulation.
Krebs and Johansen (2013) looked at data from the US National Survey on Drug Use and Health. Their analysis showed that people who had used psychedelics had no greater risk of mental health problems. If anything, they were less likely to have experienced severe psychological distress. The researchers also found that people who had used psilocybin were less likely to experience panic attacks or be prescribed psychiatric medication.
This research strongly suggests that the beneficial effects of psilocybin and other psychedelics are not limited to clinical settings and do not always require the supervision of a specialized psychiatrist.