Patients with severe depression who have exhausted standard treatment options could find rapid relief in “laughing gas”, with a major new study showing symptoms can improve within 24 hours.
A meta-analysis led by the University of Birmingham reveals that clinically administered nitrous oxide offers a promising alternative for the 48 per cent of UK patients who see limited benefit from standard antidepressants.
The findings, published in eBioMedicine, indicate that the gas targets glutamate receptors in a similar mechanism to ketamine, allowing it to bypass the weeks-long lag time associated with traditional medication.
Researchers assessed data from seven clinical trials and found that a single treatment of inhaled nitrous oxide at 50 per cent concentration produced significant reductions in depressive symptoms within a day.
However, the team noted that while the initial relief was rapid, the effects were not sustained at one week, suggesting that repeated dosing is required to maintain the clinical benefit.
Half effective
“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 Kiranpreet Gill, a PhD researcher at the University of Birmingham and the study’s first author.
“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.”
The analysis showed that side effects were generally mild, including nausea, dizziness and headaches, all of which resolved quickly without medical intervention.
The team is now preparing the first NHS trial to assess how the treatment can be delivered safely in a clinical setting.
“This is a significant milestone in understanding the potential of nitrous oxide as an added treatment option for patients with depression who have been failed by current treatments,” said Professor Steven Marwaha, senior author and Honorary Consultant Psychiatrist at Birmingham and Solihull Mental Health Foundation Trust.
“This population has often lost hope of recovery, making the results of this study particularly exciting.”