Nitrous Oxide May Be Effective Against Treatment-Resistant Depression
Researchers have tried countless chemicals, drugs, and activities to help treat depression, but a fast and effective treatment may have been hiding in the dentist’s office this whole time. A new study says nitrous oxide, better known as laughing gas, shows promise as a therapy for relieving depressing in those resistant to standard treatments.
In a small trial, a team of researchers led by Peter Nagele, MD, professor of anesthesiology at Washington University School of Medicine in St. Louis, recruited 20 patients with treatment-resistant depression.
“This is an exciting first step and evidence that there might be a real positive effect [of laughing gas],” Dr. Nagele told dailyRx News. “Given the small sample size, we cannot make any robust predictions as to how the treatment will do in a larger patient population.”
While common treatments including antidepressants and psychological counseling can relieve depression symptoms in the majority of those with depression, approximately one-third of individuals with major depression are resistant to these treatments.
The participants went through two sessions. In the first, they were given a gas mixture of half oxygen and half nitrous oxide, the same mix used in dentistry. For the second session, participants were given a placebo mixture of oxygen and nitrogen.
Dr. Nagele and colleagues saw that two-thirds of patients treated with nitrous oxide showed improvements in symptoms shortly after treatment. One-third of the same patients had improved after being given a placebo.
For the study, participants were asked to report on the severity of their symptoms two hours after treatment and 24 hours after treatment. The team tracked levels of sadness, feelings of guilt, suicidal thoughts, anxiety, and insomnia.
After 24 hours, seven patients reported mild improvements in symptoms, while another seven reported significant improvements. Another three participants said their symptoms disappeared almost instantaneously. Notably, no patient reported symptoms getting worse following treatment with nitrous oxide.
Study author Charles R. Conway, MD, professor of psychiatry at Washington University, said many of the patients receiving nitrous oxide reported a rapid improvement.
“Most patients who improved reported that they felt better only two hours after treatment with nitrous oxide,” Dr. Conway said in a press release. “That compares with at least two weeks for typical oral antidepressants to exert their beneficial, antidepressant effects.”
The fast effect of the treatment is in stark comparison to antidepressants which commonly take weeks before providing symptom relief.
However, Dr. Nagel says he does not see laughing gas becoming a widely used alternative to antidepressants. “We see [laughing gas] as potential for situations where rapid antidepressant effects are warranted and for patients with treatment-resistant depression,” he said.
This research was presented Dec. 9 at the annual meeting of the American College of Neuropsychopharmacology in Scottsdale, AZ. It was published online the same day in the journal Biological Psychiatry.