Recreational nitrous oxide misuse is resulting in serious neurological impairment and persistent disability among users

To the Editor: Published evidence recognises that the recreational misuse of nitrous oxide (N₂O) can be associated with vitamin B₁₂ deficiency and subacute combined degeneration of the spinal cord.1 Misuse of N₂O is increasing,2 with canisters (known as “nangs” or “whippits”) readily available for legal purchase in convenience stores and online ostensibly for the purpose of whipping cream.

In recent years, an increase in the number of emergency presentations and acute hospital admissions related to N₂O misuse has been recorded in Australia.3,4 We have also seen an increase in the number of patients requiring specialist multidisciplinary rehabilitation for severe impairments, including proprioceptive deficits, ataxia, disabling lower limb weakness and persistent gait abnormalities. Over recent years, a growing number of patients have been admitted to our inpatient metropolitan Sydney rehabilitation unit with serious disabilities related to N₂O misuse. In line with published reports, our experience confirmed that patients are often university students (typically aged < 30 years).3,4

As acute medical specialties recognise the significance of these presentations,3,4 we highlight that the resulting disabilities can remain for months or years at functional, vocational and emotional levels, and many will be lifelong. This will impose a significant disability burden that will require ongoing management by specialist rehabilitation and disability services and will have an impact on the wider health care utilisation and cost.

As long as N₂O remains legal and accessible and is perceived by many as seemingly innocuous, users will remain largely unaware of the severity and risk presented by its long term use. Compared with messaging surrounding other “hard drugs”, most of the literature and the public health messaging in Australia do not appear to emphasise the potential for catastrophic, permanent injury associated with the misuse of N₂O.

Given the emerging disability burden resulting from recreational N₂O misuse, we recommend enhancing existing public awareness campaigns.5 We suggest that educational resources place greater emphasis on the potential for serious, long term impairments and that education campaigns be targeted to most susceptible people via tertiary and/or secondary education establishments. Widespread restrictions on N₂O purchase should also be considered. Such measures may help prevent permanent and devastating disabilities resulting from the misuse of this easily accessible substance.