Psychedelic Drugs to Treat Depression

 

Major Depressive Disorder (MDD), which affects an estimated 6% of adults worldwide, is more than just “feeling down”, it is an, often debilitating, illness with mechanisms that are not fully understood. (Otte et al, 2016) Established treatments do exist, such as therapy and antidepressants, but an estimated 10%-30% of individuals experiencing MDD are categorized as having “treatment resistant depression”, MDD that is nonresponsive or does not resolve after treatment with multiple antidepressants (Al-Harbi, 2012).

For individuals with treatment resistant depression, psilocybin, the substance in “magic mushrooms'' that causes hallucinations, may be a part of their next treatment. In one study, 60-80% of patients experiencing cancer related depression or anxiety experienced an improvement in these symptoms that lasted 6.5 months after treatment (Ross et al, 2016). In a separate study of patients with treatment resistant depression, all participants saw some improvement in MDD symptoms, as well as increased brain activity according to CMFB scans, for at least 1 week after treatment, and 47% continued to see these improvements 5 weeks after treatment (Carhart-Harris et al, 2017). A follow up analysis to this same study found that those patients who continued to see improvement at 5 weeks post treatment did not report a return of depressive symptoms 6 months after the initial treatment (Carhart-Harris et al, 2018).

Antidepressants are generally taken daily and may not have any effect on MDD for several weeks (Otte et al, 2016). However, psilocybin appears to reduce depressive symptoms as soon as 7 hours after administration, and may improve depressive symptoms for months after a single dose (Ross et al, 2016).  That said, there aren’t currently many studies about psilocybin, and those we do have work with small sample size. 

While wide-spread clinical use of psychedelics will have to wait for more research, it is encouraging to note that a reliable treatment for treatment resistant depression may be possible.

Works Cited

Al-Harbi K. S. (2012). Treatment-resistant depression: therapeutic trends, challenges, and future directions. Patient preference and adherence, 6, 369–388. https://doi.org/10.2147/PPA.S29716

Carhart-Harris, R. L., Roseman, L., Bolstridge, M., Demetriou, L., Pannekoek, J. N., Wall, M. B., Tanner, M., Kaelen, M., McGonigle, J., Murphy, K., Leech, R., Curran, H. V., & Nutt, D. J. (2017). Psilocybin for treatment-resistant depression: fMRI-measured brain mechanisms. Scientific reports, 7(1), 13187. https://doi.org/10.1038/s41598-017-13282-7

Carhart-Harris, R. L., Bolstridge, M., Day, C., Rucker, J., Watts, R., Erritzoe, D. E., Kaelen, M., Giribaldi, B., Bloomfield, M., Pilling, S., Rickard, J. A., Forbes, B., Feilding, A., Taylor, D., Curran, H. V., & Nutt, D. J. (2018). Psilocybin with psychological support for treatment-resistant depression: six-month follow-up. Psychopharmacology, 235(2), 399–408. https://doi.org/10.1007/s00213-017-4771-x

Otte, C., Gold, S. M., Penninx, B. W., Pariante, C. M., Etkin, A., Fava, M., Mohr, D. C., & Schatzberg, A. F. (2016). Major depressive disorder. Nature Reviews Disease Primers, 2(1). https://doi.org/10.1038/nrdp.2016.65

Ross, S., Bossis, A., Guss, J., Agin-Liebes, G., Malone, T., Cohen, B., Mennenga, S. E., Belser, A., Kalliontzi, K., Babb, J., Su, Z., Corby, P., & Schmidt, B. L. (2016). Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: a randomized controlled trial. Journal of psychopharmacology (Oxford, England), 30(12), 1165–1180. https://doi.org/10.1177/0269881116675512