Randomised, placebo-controlled, double-blind crossover pilot study (n=21) testing up to 50% nitrous oxide in oxygen versus placebo (50% nitrogen/50% oxygen) for one hour in patients with major depressive disorder.
This pilot study randomises participants with major depressive disorder to receive 50% nitrous oxide/50% oxygen or placebo (50% nitrogen/50% oxygen) in a double-blind crossover design with two 1-hour sessions one week apart.
Depression severity is assessed by blinded raters using the Hamilton Depression Rating Scale at baseline, 30 minutes and 2 hours post-treatment; rationale is that nitrous oxide, an NMDA-receptor antagonist like ketamine, may produce rapid antidepressant effects with simpler administration.
Population includes non-treatment-resistant and treatment-resistant MDD subjects; safety monitoring and standard medical therapy are continued throughout.
Randomised, double-blind crossover comparing 50% nitrous oxide/50% oxygen with 50% nitrogen/50% oxygen (placebo) in two 1-hour sessions one week apart.
Up to 50% N2O in oxygen administered for 60 minutes.
Placebo: 50% nitrogen (inert)/50% oxygen for 60 minutes; identical administration and setup.