Nitrous Oxide Sourcing, Use and Harms: Insights From Australians Who Use Ecstasy/MDMA and Other Illicit Stimulants.

Introduction: Increasing harms associated with nitrous oxide use have raised concerns, but limited evidence exists to inform harm reduction. This study aimed to identify how nitrous oxide is sourced, the products/forms used, awareness of health risks, engagement in harm reduction and experience of neurological symptoms.

Methods: Data were collected via annual interviews (2021-2023) with cross-sectional convenience samples of Australians who regularly used ecstasy/MDMA and/or other illicit stimulants and reported past 6-month use of nitrous oxide (2021 n = 379; 2022 n = 315; 2023 n = 284).

Results: The most commonly reported source of nitrous oxide in the past 6 months was convenience stores, followed by 24/7 delivery services. Sourcing from these retailers was also associated with heavier use. Reported use of larger cylinders (> 8 g) increased from 6% in 2021 to 26% in 2023. While most respondents demonstrated awareness of neurological risk (e.g., brain damage 63%; nerve damage 20%), only one-fifth identified the risk of Vitamin B12 depletion and 17% were unaware of any risks. Almost one-third (30%) reported limiting use per session, 36% limited frequency and 36% took no precautions. Reports of neurological symptoms rose from 5% in 2021 to 14% in 2023 among cross-sectional samples, with few (n ≤ 5) receiving treatment.

Discussion And Conclusions: Findings suggest increasing use of larger cylinders, alongside increasing neurological harms. Given the evolving regulatory and risk environment, close surveillance of usage and market trends is needed. The findings reinforce the need for balanced regulation and targeted education of retailers, clinicians and consumers to reduce harmful patterns of use and encourage early intervention.