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Methylenedioxymethamphetamine (MDMA)



Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision May 2020| Content last modified May 2020
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MDMA (3,4-methylenedioxymethamphetamine) is an amphetamine analog with stimulant and hallucinogenic effects.

MDMA acts primarily on neurons that produce and release serotonin, but it also affects dopaminergic neurons. MDMA is usually taken as a pill; effects begin 30 to 60 minutes after ingestion and typically last 4 to 6 hours. MDMA is often used at dance clubs, concerts, and rave parties. (See also Amphetamines.)

Symptoms and Signs

MDMA causes a state of excitement and disinhibition and accentuates physical sensation, empathy, and feelings of interpersonal closeness. Toxic effects are similar to those of the other amphetamines but are less common, perhaps because use is more likely to be intermittent. However, even with casual use, significant problems such as hyperthermia and centrally mediated hyponatremia may occur. The effects of intermittent, occasional use are uncertain. Rarely, fulminant hepatic failure occurs.

Chronic, repeated use may cause problems similar to those of amphetamines, including dependence. Some users develop paranoid psychosis. Cognitive decline may also occur with repeated, frequent use.


  • Clinical evaluation

MDMA may not be detected by routine urine immunoassay drug screens.


  • Symptomatic treatment for acute toxicities and dependency

Treatment for acute MDMA toxicity and dependency is similar to treatment for amphetamines, although treatment for acute overdose is less commonly needed.

More Information

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