Mental health: laughing gas effective against depression ? What this new study says

Santé mentale : le gaz hilarant efficace contre la dépression ?

Nitrous oxide, laughing gas, has a bad press. The cause is an increase in recreational consumption among adolescents and young adults when the health risks are potentially very serious, even fatal. However, it could change the lives of depressed people who are resistant to medication.

Nitrous oxide, also known as nitrous oxide, particularly available in whipped cream siphon cartridges, be rehabilitated. "Laughing gas lacks credibility and suffers from a bad image, particularly because of its recreational use which is not without risk", explains Inserm .

Indeed, the one that also calls itself the proto, whose consumption has increased among 15-25 year olds in recent years, can cause serious effects. Among others: asphyxiation from lack of oxygen, cold gas burns, dizziness, disorientation, loss of consciousness and falls. "In case of repeated consumption at short intervals and/or in high doses, severe neurological, hematological, psychiatric or cardiac disorders may occur" , notes the Interministerial Mission to Combat Drugs and Addictive Behaviors (Mildeca).

Reduced symptoms after a single exposure

But nitrous oxide would also be associated with antidepressant effects. Psychiatrist Thomas Desmidt from Tours University Hospital (Indre-et-Loire) highlighted them with the iBrain team from Inserm, using medical imaging. They exposed thirty women for one hour to a gas mixture containing as much O2 as N2O, called an equimolar mixture of oxygen and nitrous oxide (Meopa). ;, the most common form of use of laughing gas in a medical environment.

Aged 25 to 50, around twenty had medication-resistant depression, the other ten were volunteers without depression. Result: exposure to Meopa, administered by mask, significantly reduced the symptoms of 45% of patients. According to Thomas Desmidt, these positive results confirm previous studies: "positive responses to N2O in depression are of the order of 20 to 40%, after a single exposure to product".

A clinical routine within 4 to 5 years ?

Functional MRI showed in nine patients a decrease in cerebral connectivity with areas of the brain known to activate simultaneously in depressed patients. "The Meopa session allows ’to’turn off’ this brain network whose hyperactivity is synonymous with depressive suffering and ruminations, explains the researcher. An ultrasound method suggests a link between the vasodilatory properties of nitrous oxide and its antidepressant effect.

These encouraging results will still need to be validated on a larger scale. It will also remain to set the percentage of N2O in the mixture, the time and the number of exposure… hellip; Several randomized therapeutic trials should emerge in depressed elderly people but also in patients who present to the emergency room with suicidal thoughts. "In four to five years, we should have enough elements on hand, I hope, to use nitrous oxide in clinical routine&quot ;, concludes Thomas Desmidt.

Note: according to a 2021 survey, 12.5% ​​of people aged 18 to 25 had experienced a depressive episode characterized in the 12 least which preceded the survey. The study highlighted an unprecedented acceleration in depressive episodes between 2017 and 2021. According to Inserm, characterized depressive disorder affects approximately 15 to 20% of the general population over the entire lifespan and is characterized by a succession of ;rsquo;characterized depressive episodes. The risk of suicide is present in 10 to 20% of patients. Nearly 30% of patients are resistant to any form of pharmacological treatment.