Divergent Effects of Psilocybin for 2 Patients Participating in a Psilocybin-assisted Cognitive Behavioral Therapy Trial for Major Depressive Disorder.

We present divergent experiences of 2 patients who participated in a clinical trial of psilocybin-assisted cognitive behavioral therapy for major depressive disorder. Both patients participated in an open trial involving 2 drug administration sessions separated by one month (10 and 25 mg, respectively) along with 12 sessions of cognitive behavioral therapy. The first of the 2 patients had powerful and beneficial experiences on psilocybin that led to immediate and sustained antidepressant effects over the 7-month study. The second participant reported significant challenges with psilocybin and minimal to no antidepressant effects following the drug administration. We present the clinicians' experiences who treated both patients. Finally, we theorize and discuss areas of future research to elucidate how psilocybin can yield the greatest psychiatric benefit, the conditions within the patient that can lead to (or inhibit) psychiatric benefit, and the psychosocial environment that can best facilitate psilocybin therapy.