Short-term treatment with nitrous oxide has shown promise for treating depressive disorders. The corresponding study was published in eBioMedicine.
“Depression is a debilitating illness, made even more so by the fact that antidepressants make no meaningful difference for almost half of all patients diagnosed with it,” said first author of the study, Kiranpreet Gill, a PhD researcher funded by the Medical Research Council at the University of Birmingham, in press release.
“This study brings together the best possible evidence indicating that nitrous oxide has the potential to provide swift and clinically significant short-term improvements in patients with severe depression,” she added.
For the study, the researchers reviewed four protocol papers alongside seven clinical trials involving 247 participants with depressive disorders including major depressive disorder (MDD), treatment-resistant depression (TRD), and bipolar depression. Most of the trials investigated a single session of 25% or 50% nitrous oxide for 20-60 minutes.
Ultimately, the researchers found that three trials administering 50% nitrous oxide in a single session significantly reduced depressive symptoms within 24 hours, although effects were not sustained after a week. They found, however, that repeated dosing over several weeks resulted in more durable improvement.
“Our analyses show that nitrous oxide could form part of a new generation of rapid-acting treatments for depression,” said Gill.
The treatment was generally well-tolerated, although some patients experienced mild and transient adverse effects like nausea, dizziness, and headaches. Those taking higher doses- at 50% concentration- were more likely to experience side effects. None of the studies reported short-term safety concerns.
The researchers wrote that future research should include larger, methodologically rigorous randomized controlled trials to confirm the durability of nitrous oxide’s antidepressant effects beyond the short-term, and to evaluate longer-term safety. They added that trials should also investigate whether nitrous oxide augments existing antidepressants or may be used as a standalone treatment.
Sources: EurekAlert, eBioMedicine
