Psilocybin-Assisted Therapy for Treatment-Resistant Depression in Bipolar II Disorder

Bipolar disorders (BD) are lifelong conditions characterized by recurrent episodes of depression and (hypo)mania. Statistics Canada data indicate over a million Canadians are affected by this illness. Bipolar II disorder is characterised by recurrent episodes of hypomania and depression and individuals with BD-II are symptomatic about 50% of the time despite treatment. The majority of this time is spent being depressed thus there is an urgent need to develop new treatments that are safe and effective. Psilocybin, a naturally occurring psychedelic compound found in mushrooms, has been noted to result in an increase in psychological well-being in healthy volunteers as well as have antidepressant effects when administered in conjunction with psychological support. Two recent open-label pilot trials of Psilocybin-Assisted Therapy (PAT) in treatment-resistant depression, including BD-II participants, demonstrated high response rates and excellent tolerability, thereby providing strong justification for the current study.