Clinical Trial

Sustained Mood Improvement With Laughing Gas Exposure

Study acronym: SMILE
Not Yet Recruiting Phase 3
View on ClinicalTrials.gov →
Summary
Multi-centre, parallel group, blinded, 1:1 randomized controlled trial to determine the effect of nitrous oxide on reducing symptoms of depression in patients with treatment resistant depression.
Protocol Amendment History 1 amendment
This ClinicalTrials.gov record has been amended once since 2025-11-21.
Trial Details
NCT Number NCT07262008
Lead Sponsor Women's College Hospital
Collaborators: Anesthesia Clinical Trials Unit (Department of Anesthesia and Pain Management), University Health Network, Toronto, Sunnybrook Health Sciences Centre, Unity Health Toronto, Canadian Institutes of Health Research (CIHR)
Conditions Major Depressive Disorder, Treatment Resistant Depression
Enrollment 120 participants
Start Date 2026-02-01
Primary Completion 2027-02-01 (estimated)
Study Completion 2028-09-01 (estimated)
Updated on ClinicalTrials.gov 2025-12-10