Skip to main content
OpenTrials
Completed

NCT Number: NCT02139540

Nitrous Oxide as Treatment for Major Depression - a Pilot Study

Major depressive disorder (MDD) is a global medical problem with significant shortcomings in current therapy. Chief among these is the delay between initiation of pharmacologic therapy and clinical improvement in symptoms. Recently ketamine, an NDMA-receptor antagonist has been shown to rapidly and effectively reverse the symptoms of MDD. Nitrous oxide, another NMDA-receptor antagonist, may produce the same effect with a cleaner side-effect profile and perhaps without the need for intravenous access and anesthesia personnel. Therefore, we propose conducting a pilot randomized placebo controlled double-blind crossover study in which patients will receive up to 50% nitrous oxide in oxygen or up to 50% oxygen in air for a period of one hour in addition to standard medical therapy. Depression severity will be assessed by a blinded observer pre-treatment, 30 minutes and 2 hours post treatment using the Hamilton depression rating scale.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Depression Behavior Behavioral Symptoms Depressive Disorder Depressive Disorder, Major Major Depressive Disorder Mental Disorders Mood Disorders

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Barnes-Jewish Hospital

St Louis, Missouri, 63110, United States

About this study

We will study 20 patients with non-treatment resistant major depression and 20 patients with treatment-resistant major depression, defined as failure of at least 2 antidepressants in the current depressive episode and 3 lifetime medication failures.

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

  • Adults 18-65 years of age
  • Major depressive disorder without psychosis with as determined by structured interview using the Mini-International Neuropsychiatric Interview (MINI).

(baseline )

  • HDRS-21 score of >18
  • Good command of the English language

Exclusion criteria

History of:

  • Bipolar disorder
  • Schizoprenia
  • Schizoaffective disorder
  • Obsessive-compulsive disorder, panic disorder
  • Substance abuse or dependence (except for remote substance abuse or dependence with remission at least 1 year prior to the study and except for nicotine use disorders)
  • Axis II diagnoses that may interfere with the patient's ability to improve on nitrous oxide
  • Acute medical illness that may pose subject at risk during nitrous oxide administration
  • Active suicidal intention (inability to contract for safety)
  • Active psychotic symptoms
  • Patients with significant pulmonary disease and/or requiring supplemental oxygen
  • Contraindication against the use of nitrous oxide:
  • Pneumothorax
  • Bowel obstruction
  • Middle ear occlusion
  • Elevated intracranial pressure
  • Chronic cobalamin and/or folate deficiency treated with folic acid or vitamin B12
  • Pregnant patients
  • Breastfeeding women
  • Previous administration of NMDA-receptor antagonists (e.g., ketamine) within the last 3 months
  • Current electro-convulsive therapy treatment
  • Any active suicidal ideation, intention, or planning (clinical assessment of suicidality will be used)

Treatment and study plan

Nitrous Oxide

Drug

Patients will receive either up to 50% nitrous oxide/50% oxygen for 1 hour or "placebo" (50% nitrogen [inert]/50% oxygen) in two separate sessions. Both sessions will be 1 week apart.

Other names: Laughing Gas

Placebo

Drug

50% nitrogen [inert]/50% oxygen - otherwise completely identical administration and setup

Other names: 50% nitrogen [inert]/50% oxygen

Primary outcomes

  1. Change in Hamilton Depression Rating Scale HDRS-21

    Time frame: baseline and 24 hours

    (21-point Hamilton Depression Rating Scale) Scoring is based on the first 17 items on the 21 point scale. Eight items are scored on a 5-point scale, ranging form 0=not present to 4= severe. Nine are scored from 0-2.

Secondary outcomes

  1. Change in Quick Inventory of Depressive Symptomatology - Self Report - QIDS -SR

    Time frame: baseline and 24 hours

    [Quick Inventory of Depressive Symptomatology - Self Report] An item-by-item severity scale of 0 to 3, with possible total scores ranging from 0 to 84. The items on the scale are added together for a total score. Higher scores mean worse outcome.

Sponsors and collaborators

Lead sponsor

Washington University School of Medicine

Other

Registry information

Important dates

Study start
2012
Primary completion
2015
Study completion
2015
First posted
May 15, 2014
Registry last updated
Jan 27, 2020

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.