(R)-MDMA
psychoactive drug taken by mouth
(R)-3,4-Methylenedioxy-N-methylamphetamine ([R]-MDMA), also known as (R)-midomafetamine or as levo-MDMA, is the (R)- or levorotatory (l-) enantiomer of 3,4-methylenedioxy-N-methylamphetamine (MDMA; midomafetamine; "ecstasy"), a racemic mixture of (R)-MDMA and (S)-MDMA. Like MDMA, (R)-MDMA is an entactogen or empathogen. It is taken by mouth.
The drug is a serotonin–norepinephrine releasing agent (SNRA) and weak serotonin 5-HT2A receptor agonist. It has substantially less or no significant dopamine-releasing activity compared to MDMA and (S)-MDMA. In preclinial studies, (R)-MDMA shows equivalent therapeutic-like effects to MDMA, such as increased prosocial behavior, but shows reduced psychostimulant-like effects, addictive potential, and serotonergic neurotoxicity. In clinical studies, (R)-MDMA produces similar effects to MDMA and (S)-MDMA, but is less potent and has a longer duration.
(R)-MDMA was first described in enantiopure form by 1978. Under the developmental code names EMP-01, developed by AtaiBeckley, and DT402 (formerly MM402), developed by Definium Therapeutics (formerly MindMed), it is under development for the treatment of post-traumatic stress disorder (PTSD), social phobia, and pervasive development disorders (PDDs) such as autism. It is thought that (R)-MDMA might have a better safety profile than MDMA itself whilst retaining its therapeutic benefits.
Use and effects
(R)-MDMA has a dose of 125 to 300 mg orally and a duration of 3.5 to 5.2 hours. It has been estimated that doses of 125 mg MDMA, 100 mg (S)-MDMA, and 300 mg (R)-MDMA are equivalent.
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