A single 25-mg dose of psilocybin with psychological support was feasible to deliver within an NHS setting and produced large preliminary reductions in depressive symptoms among adults with treatment-resistant depression. The Phase 2 feasibility trial also found the treatment was generally well tolerated, although functional unblinding and expectancy effects mean larger, longer efficacy studies are needed.

The first randomized controlled trial in the U.K. has found that a single dose of psilocybin, the active compound found in "magic mushrooms," produced significant improvements in depression compared with ...