MDAI (5,6-methylenedioxy-2-aminoindane) is a drug developed in the 1990s by a team led by David E. Nichols at Purdue University. It acts as a non-neurotoxic and highly selective serotonin releasing agent (SSRA) in vitro and produces entactogen effects in humans.
MDAI has been advertised as a designer drug. It started to be sold online from around 2007, but reached peak popularity between about 2010–2012, after bans on mephedrone came into effect in various countries. Internet-sourced products claimed to be MDAI have been shown variously to contain mephedrone or other substituted cathinone derivatives, and mixed compositions of inorganic substances, while generally containing no MDAI. The number of internet searches for MDAI has been considerably higher in the UK compared to Germany and the USA. MDAI is only non-neurotoxic in isolation but may become neurotoxic when mixed with other drugs. Three deaths were linked to MDAI use in the UK during 2011–2012, all involving symptoms consistent with serotonin syndrome. Two of these also involved other drugs while one death appeared to be from MDAI alone.