Using Laughing Gas to Treat Depression (AUDIO) WashU Medicine Your browser does not support the audio element. Caption Nitrous oxide, often called laughing gas, has been used in medicine and in dentistry for more than 150 years. But researchers at Washington University School of Medicine in St. Louis may have found a new use for it: as a treatment for clinical depression. Jim Dryden reports... Credit Washington University BioMed Radio Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.