Nitrous oxide (laughing gas) and alkyl nitrites (poppers) rank among the least harmful recreational drugs when assessed on 16 criteria including dependence, injury, and economic cost. An expert panel using Multi-Criteria Decision Analysis scored nitrous oxide at 6 and poppers at 5 on a 0–100 overall harm scale, placing them just above magic mushrooms (psilocybin). Nitrous oxide scored higher for dependence, environmental damage, mental impairment, and family adversities; poppers scored higher for injury, drug-related damage, economic cost, and mortality. The findings aim to inform UK policy decisions, as nitrous oxide possession is not currently controlled under the Misuse of Drugs Act.
Before psychedelic-assisted therapy can be integrated into mainstream medicine, a thorough understanding of its risks and adverse effects is critical. Current clinical trials have left knowledge gaps, and a comprehensive analysis of human receptor pharmacology is needed to guide safe dosing and identify drug-drug interactions with common antidepressants, antipsychotics, and anticonvulsants. Post-approval pharmacovigilance will be essential for patient safety, and future trials must include more ethnically diverse populations. This innovation in psychiatry requires careful, stepwise safety and risk-benefit evaluations to maximize patient benefit.