Overview
- An eBioMedicine review pooling early trials reports that controlled nitrous oxide can reduce depressive symptoms within hours.
- The synthesis combined seven completed studies with 247 participants spanning major depression, treatment-resistant cases and bipolar depression.
- A single 50% dose produced measurable improvement at two to 24 hours, with benefits generally waning by about one week.
- Multiple sessions over several weeks yielded more sustained gains and higher remission rates than single treatments.
- Higher concentrations tended to work better but caused more mild, transient side effects such as nausea, headache and dissociation, prompting calls for larger, longer trials to define dosing and long-term safety.