There’s a growing interest in psychedelics’ potential to address psychological problems. Specifically, psilocybin (found in psychedelic mushrooms), when used alongside therapy (commonly referred to as “psychedelic-assisted therapy”), is believed to have the potential to alleviate treatment-resistant depression and various other psychological issues. But what about the possible drawbacks? Are we ignoring potential pitfalls of endorsing psychedelic-assisted therapy? Have we fully accounted for the negative effects? Has the other shoe dropped with regards to negative effects of these interventions? The answer is no. There is still work to be done!

Today, my colleagues and I published a paper investigating the negative outcomes of psychedelic-assisted therapy. We interviewed therapists who administer this form of therapy to assess potential short-term and long-term adverse effects.

Our findings revealed short-term negative reactions to psilocybin dosing sessions, including physical, cognitive, and emotional reactions. There were undesirable changes in the therapy relationship, such as risky power dynamics, and challenging self-experiences where patients found the dosing frightening, invasive, and overwhelming.

Even more concerning were the long-term negative effects. These comprised destabilization, where clients’ defense or avoidance mechanisms were disrupted, leading to decreased coping abilities. Clients also experienced difficulties adjusting to life post-treatment, with the insights gained during therapy overwhelming them to such an extent that their coping abilities were further diminished.

Beware of unearned wisdom

Carl Jung

We also noted complications in the treatment relationship, such as clients desiring continued contact after treatment ends, often due to dependency, idealization, and idolization, but also because of romantic transference and blurred professional boundaries. Lastly, there were undesirable outcomes, including worsening of the client’s original condition or the development of new symptoms.

While the literature presents promising findings, we must proceed with caution before endorsing psilocybin as a viable treatment for mental disorders. The negative effects of these treatments remain understudied.

You can read our open-access article by clicking here or on the link below. We hope our study encourages researchers and clinicians to consider potential adverse effects more thoroughly before embracing this form of treatment. It is not self-evident that the other shoe has dropped.

Link to the article

Nordin, M., Hlynsson, J. I., Håkansson, J., & Carlbring, P. (in press). A Double-Edged Sword: Insights from Practitioners on the Short and Long-Term Negative Effects of Psilocybin-Assisted Psychological Interventions. Journal of Psychedelic Studies. https://doi.org/10.1556/2054.2024.00337