Using nitrous oxide to treat acute suicidal thoughts

Nitrous Oxide in the Treatment of Acute Suicidal Ideation

This study is testing if nitrous oxide can quickly help people who are having serious thoughts of suicide feel better.

Quick facts

• Phase: PHASE2
• Study type: Interventional
• Enrollment: 85 (estimated)
• Ages: 18 Years to 65 Years
• Sex: All
• Sponsor: University of Zurich (other)
• Locations: 1 site (Zurich)
• Trial ID: NCT06636357 on ClinicalTrials.gov

What this trial studies

This study aims to explore the rapid antisuicidal effects of nitrous oxide (N2O) in patients experiencing suicidal ideation. Participants will receive either nitrous oxide or a placebo during two inhalation sessions, with the first session being double-blind. A biomarker substudy will analyze hair and blood samples, as well as EEG data, to understand the mechanisms of action and predict treatment outcomes. The study focuses on individuals with moderate to severe suicidal thoughts, assessing their response to the treatment over a week.

Who should consider this trial

Good fit: Ideal candidates are individuals with moderate to severe suicidal ideation who can provide informed consent.

Not a fit: Patients with severe mental disorders, critical illnesses, or those who have used nitrous oxide recreationally in the past year may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a rapid and effective intervention for individuals experiencing acute suicidal ideation.

How similar studies have performed: While the use of nitrous oxide for treating suicidal ideation is a novel approach, other studies have explored its effects on mood and anxiety, showing promising results.

Eligibility criteria

Inclusion criteria:

* Ability to give written informed consent
* Moderate to severe suicidal ideation defined as a score ≥3 on the Montgomery-Asberg Depression Rating Scale (MADRS; Schmidtke et al., 1985) suicide item (item #10) as well as a self-report Beck Scale for Suicide Ideation (BSS; Kliem et al., 2017) items #4 plus #5 score ≥ 2
* Plasma homocysteine level ≤ 14 µmol/l

Exclusion criteria:

* Organic, including symptomatic, mental disorders (F00-F09; lifetime diagnosis)
* Schizophrenia, schizotypal and delusional disorders (F20-F29; lifetime diagnosis)
* Mental and behavioral disorders due to psychoactive substance use. Nicotine and cannabis will be ignored (F10-F19)
* Non-medical (i.e., recreational) use of inhalational N2O during the last 12 months
* Past intolerance or hypersensitivity to N2O
* Critical illness
* Severe cardiac disease
* Pregnancy or breastfeeding
* Pulmonary hypertension
* Chronic cobalamin or folate deficiency unless treated with folic acid and/or vitamin B12
* History or evidence of any other medical or neurological condition that would expose the subject to an undue risk of a significant adverse event as determined by the clinical judgment of the investigator
* Treatment with ketamine/esketamine during the last 4 weeks
* Treatment with opioid medications during the last 3 months
* Treatment with vagus nerve stimulation (VNS) or electroconvulsive therapy (ECT) within the last 3 months
* Recent (within the last 4 weeks) or current use of benzodiazepines in excess of 5 mg lorazepam or equivalent per day
* Finally, any other factors that, in the investigator's judgment, would unduly impact patient safety or compliance during the study.

Where this trial is running

Zurich

• Psychiatric University Hospital Zurich — Zurich, Switzerland (RECRUITING)

Study contacts

• Study coordinator: Angelina Frasch

Conditions: Suicidality, EEG, Suicidal Ideation, Nitrous Oxide, Biomarkers / Blood, Biomarkers / Hair, suicidality, nitrous oxide