MDMA (ecstasy) causes a strong increase in blood oxytocin levels and enhances feelings of prosociality in healthy people. The changes in prosocial feelings are more closely tied to changes in oxytocin than to changes in MDMA concentration in the blood. This suggests that oxytocin release may be a key mechanism behind the drug's characteristic social effects.
Combining MDMA (ecstasy) with alcohol impairs psychomotor accuracy even though it increases feelings of arousal and psychomotor speed. In a double-blind, placebo-controlled crossover study with 16 healthy young adults, MDMA alone boosted speed without affecting accuracy and caused arousal, while alcohol alone slowed both speed and accuracy and induced sedation. When taken together, the combination reversed alcohol-induced sedation and improved speed, but accuracy remained significantly impaired. The effects peaked 90–150 minutes after MDMA administration and then declined, except for alcohol sedation, which emerged fully after the infusion stopped. This mismatch between perceived performance and actual impairment may affect neuropsychological functioning.