Garcia, Maria RitaGomes, Nelson G. M.Silva, Diana Dias daDias da Silva, Diana Cristina2026-04-132026-04-132026-03Garcia, M. R., Gomes, N. G. M., & Dias-da-Silva, D. (2026). Rare but relevant: MDMA and hyponatraemia. Addiction, 121(3), 713–718. https://doi.org/10.1111/add.702550965-2140http://hdl.handle.net/10400.22/32212Conventionally used for its stimulant, empathogenic and entactogenic effects,3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is one of the most commonlyused psychoactive drugs, specifically among young adults and in nightlife and recrea-tional party contexts. Often perceived as a safe drug, MDMA can display an array oftoxic effects on multiple organs, with hyponatraemia (a low blood sodium concentrationthat can cause an altered mental state) being increasingly reported. Although hypona-traemia per se is among the most common electrolyte disorders encountered in clinicalcare, acute MDMA-induced hyponatraemia was first described in 1993 and constitutes alife-threatening condition if left untreated, particularly among women, who presenthigher incidence rates and increased odds of developing severe clinical effects. The pre-sent review outlines the main clinical manifestations and prevalence of MDMA-inducedhyponatraemia, its pathophysiological mechanisms and the therapeutical approaches tocorrect this electrolyte imbalance.engAntidiuretic hormone (ADH)Arginine vasopressin (AVP)EcstasyElectrolyte balanceHyperthermiaHyponatraemiaMollyPolydipsiaresearch articlehttps://doi.org/10.1111/add.702551360-0443