Using nitrous oxide to treat fibromyalgia pain

Nitrous Oxide as Treatment for Fibromyalgia

PHASE2 · University of Chicago · NCT05357066

This study is testing if inhaling nitrous oxide can help people with fibromyalgia feel less pain while they continue their usual treatments.

Quick facts

PhasePHASE2
Study typeInterventional
Enrollment50 (estimated)
Ages18 Years to 75 Years
SexAll
SponsorUniversity of Chicago (other)
Locations1 site (Chicago, Illinois)
Trial IDNCT05357066 on ClinicalTrials.gov

What this trial studies

This trial investigates the effectiveness of nitrous oxide in alleviating pain associated with fibromyalgia, a chronic condition characterized by widespread musculoskeletal pain and various other symptoms. The study aims to determine if nitrous oxide can target neurogenic pain mechanisms linked to fibromyalgia, particularly through its action on NMDA-receptors. Participants will receive either nitrous oxide gas for inhalation or a placebo while maintaining their current fibromyalgia treatment regimen. The trial will assess pain levels and other related symptoms over the course of the intervention.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 to 75 who meet the 2016 ACR criteria for fibromyalgia and report moderate to severe pain.

Not a fit: Patients with unstable medication regimens or pain from concurrent autoimmune or inflammatory diseases may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new, effective option for managing fibromyalgia pain.

How similar studies have performed: Previous studies using NMDA-receptor antagonists like ketamine have shown some success in reducing pain, suggesting potential for nitrous oxide as a novel treatment.

Eligibility criteria

Show full inclusion / exclusion criteria
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, opiates, cocaine, cannabinoids, and amphetamines.
* Current treatment with N-methyl-D-aspartate receptor (NMDAR) ligands including ketamine, amantadine, dextromethorphan, memantine, methadone, or dextropropoxyphene.
* Subjects who are pregnant, breast feeding, or planning to become pregnant during the course of the study and for 28 days after the final administration of investigational product.
* Any other serious medical condition affecting heart, lung or any other organ system.
* Any impairment, activity or situation that in the judgment of the investigator would prevent satisfactory completion of the study protocol.

Where this trial is running

Chicago, Illinois

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Fibromyalgia, Central Neuropathic Pain, Pain

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.