Millions of people around the world suffer from major depressive disorder, or MDD. This is a serious mental health condition that can affect how a person feels, thinks, and lives their daily life.
While many people find relief with antidepressant medications, a large group do not. When depression doesn’t improve after trying at least two different antidepressants, it is called treatment-resistant depression, or TRD.
A recent meta-analysis led by the University of Birmingham looked at whether nitrous oxide—commonly known as laughing gas—could offer fast help to people with major depression, especially those with TRD.
The researchers reviewed the best available clinical studies on nitrous oxide as a possible treatment. Their findings were published in the journal eBioMedicine.
Nitrous oxide is already used in medicine for pain relief, such as during dental work or childbirth. Now, researchers are exploring whether it can also lift mood. The team analyzed seven trials and four additional study protocols that tested nitrous oxide for depression, including MDD, TRD, and bipolar depression.
They found that even a single treatment session using a 50% concentration of nitrous oxide could reduce depression symptoms within 24 hours. However, these improvements usually didn’t last more than a week. When patients had several treatments over time, the benefits lasted longer, suggesting that repeated sessions may be better than a single dose.
Nitrous oxide seems to work by affecting a part of the brain’s chemical system linked to glutamate. This is the same brain pathway affected by ketamine, a fast-acting antidepressant that is already used in special clinics for severe depression.
By influencing this system, nitrous oxide might provide a quick boost in mood for people who have not responded to other treatments.
Kiranpreet Gill, the study’s first author and a PhD student at the University of Birmingham, said that depression is hard to treat and that about half of patients don’t get enough help from regular medication. She believes nitrous oxide could become part of a new group of fast-working treatments to help people who have run out of options.
The study found that nitrous oxide was generally safe. Some patients had mild side effects like nausea, dizziness, or headaches, but these didn’t last long and didn’t require extra treatment.
Although higher doses increased the chance of these effects, there were no serious safety problems reported. Still, more research is needed to confirm the long-term safety of repeated nitrous oxide use.
Professor Steven Marwaha, the senior author, called the findings exciting and hopeful, especially for people with depression who feel like nothing works. He stressed the need for more studies to understand the best way to use nitrous oxide in real healthcare settings.
The research team is now planning the first clinical trial in the NHS to test nitrous oxide as a depression treatment. This future trial will help doctors know whether it can safely become part of standard mental health care in the UK. The goal is to expand treatment options for people in need, especially those in diverse or under-served communities.
This work is part of a larger effort led by the University of Birmingham and supported by the National Institute for Health and Care Research. It connects with the work of the CALM clinic, which already provides advanced treatments like ketamine for people with severe depression.
In summary, this study shows that nitrous oxide could offer a fast and helpful new treatment for people with major depression who have not responded to other therapies. While more trials are needed, this approach has the potential to bring hope and relief to many who are still waiting for a treatment that works.
If you care about health, please read studies that scientists find a core feature of depression and this metal in the brain strongly linked to depression.
For more health information, please see recent studies about drug for mental health that may harm the brain, and results showing this therapy more effective than ketamine in treating severe depression.
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