Psilocybin with psychological support for treatment-resistant depression: six-month follow-up.
Psychopharmacology (Berl) November 8, 2017 R. L. Carhart-Harris, M. Bolstridge, C. M. J. Day et al. 978 citations
In an open-label trial, twenty patients with severe, treatment-resistant major depression received two oral doses of psilocybin (10 mg and 25 mg, one week apart) in a supportive setting. Depressive symptoms dropped markedly within the first five weeks, with large effect sizes (Cohen's d = 2.2 at week 1 and 2.3 at week 5). Nine patients responded and four achieved remission at week 5. Improvements remained significant at three and six months (Cohen's d = 1.5 and 1.4). No one sought conventional antidepressants within five weeks. The quality of the acute psychedelic experience predicted symptom reductions at five weeks. Tolerability was good, and psilocybin appears promising for unresponsive depression, though double-blind trials are needed.