4-Hydroxy-3-methoxymethamphetamine (HMMA) is an active metabolite of 3,4-methylenedioxymethamphetamine (MDMA). It is a slightly more potent stimulant than MDMA in rodents. The drug is substantially less potent than MDMA as a monoamine releasing agent in vitro. Nonetheless, HMMA has been found to induce the release of serotonin, norepinephrine, and dopamine with values of 589nM, 625nM, and 607âÂÂ2884nM, respectively, and hence acts as a lower-potency serotoninâÂÂnorepinephrineâÂÂdopamine releasing agent (SNDRA). The predicted log P of HMMA is 1.2.