Increased oxytocin concentrations and prosocial feelings in humans after ecstasy (3,4-methylenedioxymethamphetamine) administration

MDMA (3,4-methylenedioxymethamphetamine or “ecstasy”) is a recreationally used drug with remarkable and characteristic prosocial effects. In spite of abundant attention in the scientific literature, the mechanism of its prosocial effects has not been elucidated in humans. Recently, research in animals has suggested that the neuropeptide oxytocin may induce these effects. In a double-blind, randomized, crossover, and placebo-controlled study in 15 healthy volunteers, we assessed blood oxytocin and MDMA concentrations and subjective prosocial effects after oral administration of 100 mg MDMA or placebo. MDMA induced a robust increase in blood oxytocin concentrations and an increase in subjective prosocial feelings. Within subjects, the variations in these feelings were significantly and positively correlated with variations in oxytocin levels, and the correlations between these feelings and oxytocin were significantly stronger than those between these feelings and blood MDMA levels. MDMA induces oxytocin release in humans, which may be involved in the characteristic prosocial effects of ecstasy.