Could inhaling nitrous oxide treat major depression?

A phase 2 trial published in a peer-reviewed journal shows promising results with a low rate of adverse events at low doses

Inhaled nitrous oxide can effectively treat severe treatment-resistant major depression for up to two weeks, reports a phase 2 trial.

The crossover study included 24 patients with sustained and refractory depressive illness who were treated in random order with a single one-hour inhalation of either 25% or 50% of  nitrous oxide or placebo (air/oxygen).

Treatments were separated by at least four weeks.

Participants had an average of 17.5 lifetime years of

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