Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial
Through a title, you can often infer the main purpose of a study. Click on the key phrases to see what they really mean!
Study Overview
This study's main objective was to evaluate the effectiveness of psilocybin as a treatment for depressed mood and anxiety in psychologically-distressed cancer patients -- all while using the most scientifically rigorous methods possible.
Here's a breakdown of how they structured their experiment:
There were two requirements to participate in this study – 1) a life-threatening cancer diagnosis, and 2) a DSM-IV diagnosis of either anxiety or mood symptoms. This means that their symptoms have been recorded clinically.
Potential subjects were screened on the phone, and narrowed down to a pool of 51 people. Now, they were randomly sorted into the two experimental groups.
Both groups would be completing two sessions of psilocybin administration. The first group would receive a low dose of psilocybin at their first session, then a high dose at their second session. In the second group, the order was flipped, so that they’d receive their high dose first.
So what’s the difference between a low and high dose of psilocybin?
The low dose (1 mg) was meant to be an amount that would not cause any real physiological changes to the brain or body, and would have an effect similar to a placebo. The high dose (22 mg) was meant to be the full experimental amount. To maintain scientific integrity, neither the participants nor the researchers knew which people belonged to which group, which meant they were unbiased in their expectations of what would occur after each dosage.
The psilocybin sessions themselves were done in a living-room like environment, monitored by two professionals. Whichever dose they were scheduled to receive would be administered orally, in a gel capsule, and participants were encouraged to focus on their inward experiences throughout the session. Each subject would lie on the couch, wearing eye shades and headphones that played a consistent music program.
One’s expectations prior to a psychedelic experience have proven to be very influential over how the experience actually goes. To minimize this expectancy effect, no further instructions were given on what to think about or do – the experience was meant to be completely their own.
Seven hours after each psilocybin administration, when the drug effects had worn off, participants completed four different questionnaires to gauge their psychedelic experience.
In addition to the two psilocybin sessions, subjects participated in meetings with session monitors both before and after.
-
Meetings prior to the drug administration were meant to build rapport and get to know each individual participant. In anticipation, each person was told to “trust, let go, and be open” to the experience.
-
Meetings after their psilocybin experience were generally focused on new thoughts and feelings that had come up, and were modeled after typical psychotherapy sessions.
Multiple therapeutic measures were also taken to monitor each patient’s anxiety and/or mood symptoms throughout the study. These measures were taken prior to any treatment (as a baseline), 5 weeks after each psilocybin session, and about 6 months after their second and last session as a follow-up. Subjects were considered to have a “significant response” to the psilocybin treatment if their responses on the therapeutic outcome measures had decreased by more than 50%.
So, what were the results of the experiment?
After all the responses were compiled, and statistical analyses were completed, the findings of this study stirred up quite the excitement in the developing field of psychedelic research.
Here’s a visual depiction of the most compelling results:
The first chart depicts clinically significant reduction in depression and the second chart depicts clinically significant reductions in anxiety.
These two graphs show the percentage of participants who had clinically significant responses – meaning their symptoms of either anxiety, depression, or both, were lowered by over 50%. After their first session, those who got the higher (real) dose of psilocybin had a greater proportion feel clinically better than those who received a low, placebo-like dose. This also means that any positive effects on these patients’ mental health can be reliably attributed to whatever occurred during their psilocybin sessions!
Not only did the data show that psilocybin produced large and significant decreases in both clinical and self-reported measures of depression and anxiety, but increases in measures of quality of life, life meaning, death acceptance, and optimism. All of these responses were sustained 6 months after their last psilocybin experience.
As with many early psychedelic studies, the present one was limited by a relatively small group of subjects. However, after the discovery of these amazing results, psychedelics were finally taken seriously as a blossoming field of research and a promising medical treatment.