Nitrous Oxide as Treatment for Fibromyalgia

Inclusion Criteria: * 2016 American College of Rheumatology Revised criteria for fibromyalgia (2016-ACR) * Subjects 18 -75 years of age. * Self-reported pain of at least 4 on the Numeric Pain Rating Scale (NPRS) at screening and baseline. * Subject receives and agrees to remain on their stable fibromyalgia treatment plan established at least 4 weeks prior to dosing. Stable means no change in dose or any pain medication. * Ability to understand the requirements of the study, provide written informed consent, abide by the study restrictions, and agree to return for the required assessments * If currently on psychotherapy, it must have been maintained at the same frequency for 4 weeks prior to treatment. Exclusion Criteria: * Unstable doses of allowed antidepressants or muscle relaxants or dosages for any other medical condition. * Pain due to concurrent autoimmune or inflammatory disease such as rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, or other chronic widespread pain condition(s) that may confound fibromyalgia pain. * Psychiatric or cognitive disorder (e.g., current schizophrenia, severe depression, suicidal ideation, dementia, etc.) that the investigator or sponsor considers significant for this study. * Clinically significant alcohol or other substance abuse within the last 2 years, in the opinion of the investigator. * Current or recent history of medically inappropriate or illegal use of drugs of abuse including benzodiazepines, op…