Nitrous oxide use and psychiatric disorders: a retrospective clinical cohort study on prevalence and patterns.

Among 287 patients in a German psychiatric hospital, 22 (7.67%) reported having used nitrous oxide (N2O) recreationally at some point in their lives. Users tended to be younger (mean age 28 years) and most obtained the substance through friends or social events. The most common psychiatric diagnoses among users were major depressive disorder, cannabis-related disorder, and attention deficit hyperactivity disorder. The findings suggest that recreational N2O use is relatively common in psychiatric populations and that clinicians should routinely ask about it.

Study at a glance

Abstract

Nitrous oxide (N2O) is used for anesthetic purposes but has gained popularity as a recreational substance. Despite its potentially severe adverse effects, knowledge about N2O use within psychiatric populations is limited. This study aimed to evaluate the life-time prevalence and patterns of N2O consumption among patients with psychiatric disorders. A retrospective observational cohort study was conducted at the Department of Psychiatry, Psychotherapy and Psychosomatics of the Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, involving assessments of N2O use lifetime prevalence among patients in various psychiatric settings over a six-month period in 2024. Further data on demographic characteristics and psychiatric diagnoses were collected from electronic patient records. Out of 287 screened records, 22 patients (7.67%) reported a N2O use history, with a positive statistical relationship between younger age and positive lifetime prevalence (mean age: 28.14 ± 7.29 years, range 19-48 years, 6/22 female). Most users acquired N2O through low-threshold means such as friends or social events. The predominant psychiatric diagnoses among users included major depressive disorder, cannabis-related disorder and attention deficit and hyperactivity disorder. This study highlights the concerning life-time prevalence of N2O use in a clinical psychiatric sample, emphasizing the need for increased awareness and education regarding its potential risks and side effects. Given the vulnerability of this population to substance-related issues, routine assessment for N2O use should be integrated into standard psychiatric evaluations.