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MDMA (short for 3,4-methylenedioxymethamphetamine) is a widely used and abused psychoactive drug. Known on the street as “ecstasy”, it is illegal in most countries. It has no established medical uses; but it is available to qualified researchers. As shown in the hazard information table, it is toxic in numerous ways.
MDMA is a water-insoluble viscous oil and therefore difficult to handle. Because of this, it is usually prepared as an aqueous solution of its hydrochloride salt. It is a chiral molecule normally produced as the racemate. The (R)-enantiomer (shown) remains in the body, especially in blood plasma, significantly longer than its (S) counterpart.
A cautionary tale about MDMA occurred in 2013, when Tatsunori Iwamura, a pharmacy professor at Matsuyama University (Japan) allegedly instructed 11 of his students to make the drug. Iwamura has admitted to the act, which was not revealed until April of this year. At this time, the situation is still under investigation.
MDMA hazard information
GHS classification*: flammable liquids, category 2 | |
H225—Highly flammable liquid and vapor | ![]() |
GHS classification: acute toxicity, oral, category 3 | |
H301—Toxic if swallowed | ![]() |
GHS classification: acute toxicity, dermal, category 3 | |
H311—Toxic in contact with skin | ![]() |
GHS classification: acute toxicity, inhalation, category 3 | |
H331—Toxic if inhaled | ![]() |
GHS classification: specific target organ toxicity, single exposure, category 1 | |
H370—Causes damage to organs | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.
MDMA fast facts
CAS Reg. No. | 42542-10-9 |
Empirical formula | C11H15NO2 |
Molar mass | 193.25 g/mol |
Appearance | Colorless oil |
Boiling point | 105 ºC (0.4 torr) |
Water solubility | Insoluble |
MOTW update:
May 31, 2021
MDMA (3,4-methylenedioxymethamphetamine) is a widely abused psychoactive drug known on the street as “ecstasy”. MDMA, however, may have a beneficial use. Jennifer M. Mitchell at the University of California, San Francisco and colleagues there and at several other institutions worldwide report that the drug is efficacious in patients with severe post-traumatic stress disorder (PTSD).Their randomized, double-blind, placebo-controlled phase 3 study was conducted with 90 participants at 15 sites in three countries.

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