MDMA is a synthetic compound that does not exist in nature. It is structurally similar to the amphetamines.
About 20% of MDMA is excreted in the urine unchanged. The elimination half-life is approximately seven hours but, like amphetamines, alkaline urine can increase the half-life of MDMA to 16-31 hours.
Since the cross reactivity of MDMA and its metabolites in amphetamine immunoassays is very low, most laboratories employ the use of a separate MDMA screen in addition to the amphetamine screen.
