Randomised, double-blind crossover study (n=36) comparing single doses of MDMA (0.75 mg/kg and 1.5 mg/kg), methamphetamine (20 mg) and placebo in healthy volunteers to assess prosocial effects.
Randomised, double-blind, crossover within-subject design in healthy volunteers comparing placebo, low-dose MDMA (0.75 mg/kg), high-dose MDMA (1.5 mg/kg) and methamphetamine (20 mg).
Primary aim is to characterise the uniquely social or prosocial effects of MDMA versus a prototypical stimulant; outcomes include behavioural social measures and acute subjective and physiological responses.
Single placebo capsule session.
Placebo capsule.
Single 0.75 mg/kg MDMA session.
Single 1.5 mg/kg MDMA session.
Single 20 mg methamphetamine session.
Methamphetamine 20 mg (active comparator).
In a double-blind, placebo-controlled crossover trial in 36 healthy adults, the high dose of MDMA (1.5 mg/kg) — but not the lower dose — increased positive affective responses to personalised social feedback compared with placebo and methamphetamine. This suggests a potential mechanism by which MDMA may enhance social connection and support its use as a psychotherapy adjunct.