34Methylenedioxymethamphetamine

34methylenedioxymethamphetamine, commonly known as 3,4-methylenedioxymethamphetamine or MDMA, is a synthetic psychoactive drug in the phenethylamine class. It is often sold under the street names ecstasy or Molly. Purity and contents of street tablets or powders vary widely, and adulterants are common.

Chemically, MDMA is a substituted amphetamine with a methylenedioxy ring attached to the phenethylamine core. It is classified as an entactogen or empathogen due to its characteristic effects on social feelings and emotional closeness.

MDMA acts primarily by increasing release and inhibiting reuptake of serotonin, with secondary effects on dopamine and norepinephrine. This leads to elevated mood, increased feelings of closeness, and enhanced sensory perception, along with physical effects such as increased heart rate and body temperature.

Onset is typically 30 to 60 minutes after ingestion, with peak effects lasting several hours. Common subjective effects include euphoria, emotional openness, and stimulatory energy; physical effects include pupil dilation, jaw clenching, sweating, and dehydration. After-effects may include fatigue and sleep disturbance.

Risks include hyperthermia, dehydration, electrolyte imbalance, and, in rare cases, serotonin syndrome, particularly with high doses or interactions with other serotonergic drugs. Repeated heavy use has been linked to cognitive changes in some studies; long-term neurotoxicity is debated. The drug's safety profile is affected by adulterants.

MDMA was first synthesized in 1912 by Merck; it saw limited early research use in the 1950s–1970s before becoming popular as a recreational drug in the 1980s. In many countries it is a controlled substance; research into potential therapeutic uses, such as for PTSD, has expanded under regulated conditions.

Because of illegality and health risks, users are advised to obtain information about test services and harm-reduction practices, such as testing substances for adulterants, staying hydrated, avoiding overheating, and not mixing with alcohol or other drugs.