This review aims at RCT's of psychedelics used in the treatment of depression and PTSD. Psilocybin has shown an antidepressant effect in cancer patients that was sustained at 6- and 12-months follow-up. The effect of psilocybin was comparable to escitalopram in one study. Ketamine has shown effect for the treatment of resistant depression. Phase 2 and 3 trials have shown the effect of MDMA on PTSD. No serious adverse events were reported in controlled settings, but larger studies are needed to establish safety and long-term effects.