Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant


Physician Assistant Studies


Objective: The objective of this selective EBM review is to determine whether or not psilocybin is an effective treatment to reduce depression and anxiety in cancer patients with a diagnosis of an anxiety disorder, mood disorder, and/or stress disorder.

Study design: Systematic review of three cross-over randomized placebo-controlled trials published in peer reviewed journals between 2010-2016.

Data sources: All articles were published in English and were selected from Cochrane Collaboration and PubMed based on if they were relevant to my clinical question and included patient-oriented outcomes (POEMs).

Outcomes measured: Outcomes measured included self-reported anxiety and depression via the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory (BDI), respectively.

Results: Grob et al. (Arch Gen Psychiatry. 2011;68(1):71-78. doi: 10.1001/archgenpsychiatry. 2010.116) found that controlled use of psilocybin when compared with placebo improved selfreported anxiety (p<0.001) and depression (p=0.05) in cancer patients. Further study by Griffiths et al. (J Psychopharmacol. 2016;30(12):1181-1197. doi: 0269881116675513) demonstrated that a therapeutic dose of psilocybin can statistically significantly reduce both cancer-related anxiety (p<0.01) and depression (p<0.05). Lastly, Ross et al. (J Psychopharmacol. 2016;30(12):1165- 1180. doi: 0269881116675512 [pii]) found that single moderate dose psilocybin in conjunction with psychotherapy produced statistically significant clinical benefits in terms of reduction of anxiety (p<0.001) and depression (p<0.01) in patients with cancer and was significantly more effective than placebo with psychotherapy.

Conclusion: All three randomized controlled trials found a statistically significant reduction in self-reported anxiety via STAI scores when patients were treated with psilocybin versus placebo. Two of the three studies reported a statistically significant decrease in self-reported depression via BDI scores, with the third reporting substantial decrease but narrowly missing statistically significance. Future studies should be done that are not cross-over design in order to improve blinding and therefore validity of the study, and with larger, more diverse patient populations to increase the generalizability of these results.