AIMS: To determine: (1) Population rates of fatal methylenedioxymethamphetamine (MDMA)-related poisoning over the period 2016-2023, years with high closure rates in the National Coronial Information System (NDIS); (2) the case characteristics of known cases of fatal MDMA-related poisoning, 2016-2025; and (3) whether there have been changes in case characteristics of known fatal cases in the period pre-COVID (2016-2019), COVID (2020-2022) and post-COVID (2023-2025).

DESIGN: Retrospective study of fatal MDMA-related poisonings in Australia retrieved from the NCIS, 2016-2025 [Correction added on 28 September 2026, after first online publication: In the previous sentence, "NDIS" has been changed to "NCIS".].

SETTING: Australia-wide.

CASES: 217 cases of fatal MDMA-related poisoning.

MEASUREMENTS: Population rates, case characteristics, circumstances of death, toxicology, major autopsy findings.

RESULTS: There was a statistically significant increasing trend in the population rate over 2016-2019 [annual percentage change (APC) = 61.52], and a statistically significant decreasing trend over 2019-2023 (APC = -26.72). The mean age was 33.5 years, and males comprised 170 cases (78.3%). In 179 cases (82.5%) the cause of death was attributed to multiple drug toxicity. The fatal incident occurred in a private setting in 171 cases (78.8%), with 16 (7.4%) occurring at a music festival. The median MDMA blood concentration was 0.41 mg/l (range 0.00-25.0 mg/l). Cases in which death was attributed solely to MDMA toxicity had a higher median MDMA concentration than multiple drug toxicity deaths (1.7 vs. 0.30 mg/l). Psychoactive drugs other than MDMA were detected in 199 cases (91.7%), most commonly other psychostimulants (147, 67.7%) and opioids (98, 45.2%). Cardiomegaly was diagnosed in 33 cases (16.6%) in which the heart was examined, and severe coronary artery disease in 27 (13.6%). There were no statistically significant differences across time periods in age, sex, substance use issues, injecting drug use, intentionality, MDMA concentrations or diagnoses of cardiomegaly.

SUMMARY: While death rates in Australia from methylenedioxymethamphetamine-related poisoning have declined from 2019, case characteristics have remained relatively stable.