Laughter gas may be most commonly used in dentistry; But in recent years, scientists have sought to use the chemical for another purpose: depression, which resists treatment.
The results of a small trial recently published in the journal Science Translational Medicine show that low doses of laughing gas can help improve depressive symptoms in patients with severe depression that is not affected by antidepressants.
Researchers at the University of Washington in St. Louis found that a lower dose of nitrous oxide, known as laughing gas, was significantly more effective in improving the symptoms of patients with refractory depression and had fewer side effects. Both doses helped relieve symptoms more than placebo. The results are to be confirmed in a larger trial.
Treatment-resistant major depression (TRMD) is usually diagnosed after at least two antidepressants are ineffective and occurs in about one-third of patients with major depression. Researchers have turned to alternative methods because of the many failures of antidepressant therapies.
In addition to antidepressants and psychotherapy, current TRMD treatment strategies include electroconvulsive therapy and anesthesia. In a particular success, ketamine has been shown to improve depressive symptoms in just a few hours; But experts are looking for more, cheaper and safer options. Looking for other options for treating depression, researchers sought to test other anesthetics, such as nitrous oxide, which is commonly used for anesthesia.
Previous studies have shown that laughing gas improves depressive symptoms within a day of treatment. In a new study, researchers sought to find out how long laughter gas works. To that end, they enrolled 24 patients with TRMD who were randomly assigned to intermittent studies to receive placebo, low-dose, or high-dose laughing gas for one hour.
In subsequent sessions, each participant was randomly transferred to another treatment group. The researchers assessed the depressive symptoms of 20 participants who completed all three sessions using different questionnaires up to two weeks after treatment. People who received different doses of laughing gas reported a greater reduction in symptoms than others.
In the special questionnaire, the symptoms of depression on a 65-point scale were reduced by 5 to 7 points in the laughing gas group compared to the placebo two weeks after treatment. However, the high dose, which contained 50% nitrous oxide, led to side effects such as nausea and vomiting. The lower dose had milder and less frequent side effects.
After completing the study, depressive symptoms decreased by about 11 points from baseline. Charles Conway, “I have been working with these people for years and I do not expect the new methods to be effective,” said a professor of psychiatry at the University of Washington and lead author of the study. “But the trial patients, some of whom I have known for a long time, got better.”
Laughter gas may have certain advantages over other medications and treatment strategies. “This is a good option because it is available in all hospitals and laboratories,” Kozin said. Peter NagleThe author also added that the substance also has fewer serious side effects than ketamine and is not metabolized in the body. “Laughter gas enters the body in a few minutes and leaves in a few minutes,” said Negle, an anesthesiologist at the University of Chicago.
However, experts warn that due to the usual use of anesthetics, there is no safety data on their long-term use. Kara Zivin“We do not know what happens to a brain that is repeatedly exposed to the gas of laughter over long periods of time,” said a professor of psychiatry at the University of Michigan who was not involved in the study. Other experts agree that, like other drugs that affect the brain, there is a potential for abuse.
Lisa Harding, A psychiatrist at Yale Medical School who did not participate in the study, noted that 96% of the study participants were white, so it is unclear how far the findings could be extended to other populations. He said further studies should involve more people of different backgrounds to confirm the effectiveness of laughter gas in treating depression in the real world.
Although the results are preliminary and more data are needed, researchers hope their approach could be another tool to help treat TRMD quickly.