MDMA, short for 3,4-Methylenedioxymethamphetamine, is a synthetic drug commonly known as ecstasy (tablet form) or molly (crystal form). It is both a central nervous system stimulant and an entactogen, which means it produces feelings of increased energy, emotional warmth, empathy, and pleasure. It also has minor psychedelic effects that can alter sensory perception, time, and visual experiences. MDMA is often used recreationally, especially in settings like dance parties, raves, and clubs, where it has gained popularity since the 1980s. The effects typically begin within 30 to 45 minutes after ingestion and last around 3 to 6 hours. Pharmacologically, MDMA increases the release of neurotransmitters such as serotonin, dopamine, and norepinephrine in the brain, which contributes to its mood-lifting and energizing effects. It is also studied for potential therapeutic use in treating conditions like post- traumatic stress disorder (PTSD) and social anxiety in autism spectrum disorder. However, MDMA carries risks, including dehydration, hyperthermia (dangerously high body temperature), confusion, anxiety, paranoia, and potential damage to brain cells involved in memory and thinking. Overdose and adverse reactions have been reported, sometimes leading to severe health consequences or death. Moreover, street ecstasy tablets may contain unknown or harmful substances alongside or instead of MDMA. In summary, MDMA is a psychoactive drug known for its stimulant, empathogenic, and mild psychedelic effects, used both recreationally and experimentally in therapy but with notable risks and legal controls worldwide.