Skip to main content
OpenTrials
Recruiting

NCT Number: NCT03826693

Efficacy of Nitrous Oxide in OCD: Pilot Study

This study investigates whether the commonly used and well-tolerated inhaled anesthetic nitrous oxide can rapidly improve symptoms of OCD.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Obsessive-Compulsive Disorder Anxiety Disorders Mental Disorders

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Stanford University

Stanford, California, 94304, United States

Location status: Recruiting

About this study

Obsessive-compulsive disorder (OCD) is a chronic and disabling disorder characterized by recurrent intrusive thoughts and associated compulsive behaviors that is estimated to affect more than 3 million individuals in the US each year.

This study seeks to explore whether a single inhalation of nitrous oxide gas may bring about rapid symptom relief in OCD.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 18-65
  • Primary diagnosis of OCD
  • Sufficient severity of OCD symptoms
  • Ability to tolerate a treatment-free period
  • Capacity to provide informed consent

Exclusion criteria

  • Psychiatric or medical conditions that make participation unsafe
  • Pregnant or nursing females
  • Concurrent use of any medications that might increase the risk of participation (e.g. drug interactions)

Treatment and study plan

Nitrous Oxide

Drug

OCD participants in this arm will receive 50%oxygen/50% nitrous oxide admixture for 60 minutes.

Nitrogen

Drug

OCD participants in this arm will receive 50%oxygen/50% nitrogen admixture for 60 minutes.

Primary outcomes

  1. Improvement in the severity of OCD symptoms as measured by the Yale-Brown Obsessive Compulsive Scale (YBOCS)

    Time frame: 1 week

    Improvement in OCD severity is measured by the YBOCS (Yale Brown Obsessive-Compulsive Scale), a gold standard measure of obsessions and compulsions. For the YBOCS the minimum units are 0 and Maximum units on the total scale are 40. The higher the number on the YBOCS, the more severe the symptoms. Response is defined as at least a 35% reduction on the YBOCS.

Interested in participating?

Recruiting

Interested in participating?

Request Info

Sponsors and collaborators

Lead sponsor

Stanford University

Other

Collaborators

  • Brain & Behavior Research Foundation

Registry information

Important dates

Study start
2021
Primary completion
2026
Study completion
2027
First posted
Feb 1, 2019
Registry last updated
Aug 27, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.