A study has found that laughing gas can reduce the symptoms of depression of people for whom common treatments don’t seem to work.
Lughing gas could be used to treat depression. A phase II clinical trial, published June 9 in the journal Science Translational Medicine, found that nitrous oxide may help reduce symptoms in some people with depression for whom common treatments don’t seem to work. In the U.S. alone, individuals suffering from treatment-resistant depression are reportedly 17 million, so researchers are looking for new methods that work faster than drugs such as SSRIs, which can take up to six weeks to start working.
Nitrous oxide gas to treat depression
“Until the introduction of ketamine, there was no drug that could rapidly improve depressive symptoms,” explained lead study author Peter Nagele, a trauma anesthesiologist at the University of Chicago. Ketamine, which has been around for a long time, is considered a “promising” new treatment option, but one that can have serious side effects, such as increased blood pressure, hallucinations and addiction. Like ketamine, however, nitrous oxide blocks a neural receptor called the NMDA receptor, which has indicated to researchers that it could have an antidepressant effect. Laughing gas “may be the oldest drug we use in medicine,” Nagele said, noting that it should also be less risky in terms of side effects.
The new study followed an earlier phase II “proof-of-concept” study involving 20 participants, whose results, published in 2015, had suggested that nitrous oxide could have fast-acting antidepressant effects. However, many important questions had remained unanswered, such as whether a lower dose of nitrous oxide would also work with fewer side effects and how long the antidepressant effects would last.
The next phase involved 20 people with treatment-resistant depression, most of whom were women. The researchers tested two different doses of nitrous oxide (and a placebo of normal oxygen), which the participants inhaled for one hour. The researchers conducted a series of mood assessments on the patients before and after the inhalation, with a final assessment conducted four weeks after the last treatment.
The researchers found that both doses actually had a similar level of effectiveness, but the lower dose had fewer side effects such as nausea or headaches. At the end of the three-month study, 85 percent of patients experienced improvement. Eight of the 20 people went into remission, and 11 of the 20 people saw a more than 50% drop in their score on a depression scale. The researchers noted, however, that the study had limitations: some patients changed the dosage of the antidepressant during the study, people could be abusing nitrous oxide, and there were no safety data on long-term use of the substance. In addition, the study was done on a very small sample of people, so the next steps will be to expand the analysis with a more diverse sample of patients and try to address the limitations identified.
In the meantime, still on the subject of health, bubbles in space are being studied on the Iss that could help diagnose some types of cancer.
Stefania Bernardini