A single 75 mg dose of MDMA produces a dissociative state, marked by feelings of depersonalization and derealization, in healthy recreational users. Blocking the 5-HT2 receptor with ketanserin did not prevent this effect, indicating that the 5-HT2 receptor does not mediate MDMA-induced dissociation. Heart rate correlated with the dissociative state after MDMA alone, but not when ketanserin was given, suggesting heart rate changes do not directly cause dissociation. Cortisol levels and MDMA blood concentrations showed no clear relationship with dissociation. The exact neurobiological mechanism remains unknown and may be relevant to MDMA's therapeutic use.
A single high dose of psilocybin combined with therapy reduced symptoms of anxiety, depression, PTSD, and neuroticism over three months. Scores on openness and conscientiousness increased after treatment. Participants reported mystical-type experiences, emotional breakthrough, and personal growth, which—along with demographic factors—moderated the positive changes. The findings suggest psilocybin-assisted therapy can benefit mood and personality, and highlight the role of subjective experiences and demographics in optimizing this treatment.