Recreational use of nitrous oxide

Nitrous oxide (N₂O) has been used non-medically since the early 19th century, but only over the past 20 years has it become established in the recreational pharmacopeia.1 It is not regularly included in national substance use surveys, so assessing global prevalence of recreational use is difficult. In England and Wales, 9% of 16-24 year olds reported use in 2019-20, which makes N₂O the second most popular controlled substance after cannabis.2 In Australia, N₂O is grouped with other inhalants, and use by those older than 14 increased from 0.4% in 2001 to 1.7% in 2019.3 In the US, 4.5% of the population older than 12 reported in 2020 that they had used N₂O at least once in their lifetime; this has been relatively stable over the past 20 years.4

N₂O is typically consumed through inhalation from small balloons containing around 10 ml of gas. It produces short lasting euphoria and mild perceptual changes (lasting 0.5-1 minute). Occasional use is considered less harmful than for many other types of recreational substance,5 but there is a …