New research provides preliminary evidence that psychedelic drugs can improve mental health by making individuals more accepting of distressing experiences. The study, published in Frontiers in Psychiatry, adds to a growing body of literature that indicates using substances like psilocybin can result in sustain improvements in depressive symptoms.

“Psychedelic therapy has shown promise as a novel treatment for a range of mental health concerns, including major depressive disorder, distress associated with a life-threatening illness, and substance use disorders,” said study author Richard Zeifman, a PhD student at Ryerson University and research intern at the Centre for Psychedelic Research at Imperial College London.

“In contrast with the traditional pharmacological interventions, the effects of psychedelic therapy appear to last months and even years after treatment has ended. Understanding how psychedelic therapy leads to long-lasting mental health improvements across a range of conditions is not yet fully understood but is important for enhancing and delivering psychedelic therapy to individuals that may benefit from it.”


The researchers were particularly interested in the transdiagnostic construct known as experiential avoidance, meaning the tendency to avoid unpleasant thoughts and feelings. People who score high on a measure of experiential avoidance agree with statements such as “I would give up a lot not to feel bad” and “I go out of my way to avoid uncomfortable situations.”

For their study, the researchers used online advertisements to recruit a sample of 104 individuals who planned to use a psychedelic substance and a second sample of 254 individuals who planned to attend psychedelic ceremonies. Both samples completed measures of depression severity, experiential avoidance, and suicidal ideation one week before and 4 weeks after using their psychedelic substance of choice.

Zeifman and his colleagues found that the use of psychedelics in both ceremonial and non-ceremonial settings was associated with decreases in experiential avoidance, which in turn was associated with decreases in depression severity and suicidal ideation 4-weeks after psychedelic use. Psilocybin/magic mushrooms, LSD, and ayahuasca were the most commonly used substances in the study.

“Our findings suggest that one of the reasons that psychedelic therapy has positive therapeutic effects is that it helps individuals to be less avoidant and more accepting of their emotions, thoughts, and memories (even though such experiences may be distressing in the short-term),” Zeifman told PsyPost.

“More broadly, our results provide further support for the negative mental health effects associated with avoidance. This can be summed up with a saying that is often used in the context of psychedelic therapy, that ‘The only way out is through.’”

But the study — like all research — includes some caveats.

“There were important limitations to our study, including that our study was not conducted in the context of a controlled clinical trial or within a clinical sample. Accordingly, we are currently conducting research where we are comparing the effects of psychedelic therapy versus a traditional antidepressant (called escitalopram) on experiential avoidance. This research will help to further examine the possibility that psychedelic therapy leads to change through different mechanisms than do traditional pharmacological interventions for depression,” Zeifman said.

The study, “Post-Psychedelic Reductions in Experiential Avoidance Are Associated With Decreases in Depression Severity and Suicidal Ideation“, was authored by Richard J. Zeifman, Anne C. Wagner, Ros Watts, Hannes Kettner, Lea J. Mertens, and Robin L. Carhart-Harris.