Nitrous Oxide AbuseBALONNCT05540561
Biological Diagnosis and Monitoring of Chronic Nitrous Oxide Abuse
An observational study of Nitrous Oxide Abuse, run by University Hospital, Lille at 8 sites in France.
Trial summary
There is a toxicity linked to the chronic use of nitrous oxide, leading to neurological disorders such as combined sclerosis of the spinal cord. One thus frequently observes patients presenting disorders of walking or paresthesias, of more or less resolving evolution being able to go until the need for using a… Read more about this study
- Who is it for?
- Ages 14 to 65 years
- Conditions the study is for
- Nitrous Oxide Abuse
- What is being tested?
- blood collection
- How many people
- 356 participants
- Where
- 8 sitesFrance
- Study dates
- 30 Jan 2023to 30 Jul 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 14 to 65 years
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Patients using or having recently used nitrous oxide, and hospitalized during the study will be offered to participate in the study.
Who may be able to join
- A current or former recreational nitrous oxide user defined
- With associated clinical signs (group 1)
- Without associated clinical signs (group 2)
- With or without clinico-biological sequelae associated with use
- Consenting to the conduct of the study
- Socially insured
Who cannot join
- Pregnant or breastfeeding women
- Never used nitrous oxide or stopped using it more than 6 months ago
- Lack of social security coverage
- Not willing to participate in the entire study
Trial locations and contacts
8 sites in 1 country. Contact the study team or a site near you to ask about taking part.
8 sites in 1 country
France8 sites, 8 recruiting
- Recruiting
BETHUNE
Béthune
GUILLAUME GROLEZ, Dr, 03 21 64 44 44, ggrolez@ch-bethune.fr
GUILLAUME GROLEZ, Dr
- Recruiting
Boulogne Sur Mer
Boulogne-sur-Mer
MATHIEU BATAILLE, 03 21 99 30 30, m.bataille@ch-boulogne.fr
MATHIEU BATAILLE, Dr
- Recruiting
CALAIS
Calais
OLIVIER DEREEPER, 0321463360, o.dereeper@ch-calais.fr
OLIVIER DEREEPER, Dr
- Recruiting
Lens
Lens
JULIEN LANNOY, DR, 0321691511, Jlannoy@ch-lens.fr
JULIEN LANNOY, Dr
- Recruiting
Chu Lille
Lille
Guillaume Grzych, MD, 0320445962, guillaume.grzych@chu-lille.fr
Guillaume Grzych, MD
- Recruiting
Nantes
Nantes
YANN PEREON, Dr, 33 240 083 704, Yann.Pereon@univ-nantes.fr
YANN PEREON, Dr
- Recruiting
Roubaix
Roubaix
ADELINE ENDERLE, Dr, 03 20 99 14 77, adeline.enderle@ch-roubaix.fr
ADELINE ENDERLE, Dr
- Recruiting
Rouen
Rouen
LUCIE GUYANT, Dr, 0232888037, lucie.guyant@chu-rouen.fr
LUCIE GUYANT, Dr
About this study
Official title: Biological Alterations of Laughing Gas Outcomes in Neurology
There is a toxicity linked to the chronic use of nitrous oxide, leading to neurological disorders such as combined sclerosis of the spinal cord. One thus frequently observes patients presenting disorders of walking or paresthesias, of more or less resolving evolution being able to go until the need for using a wheelchair and more recently cases of thrombosis were reported Serum or urine N2O assays are rarely performed routinely, because they do not allow to ensure a real exposure due to the very short half-life of this gas in the body. Thus, other biological monitoring markers are mentioned in the literature, such as vitamin B12 or homocysteine. Unfortunately, there are still no recommendations for biological monitoring of nitrous oxide consumption. Moreover, underlying mechanisms leading to clinical outcomes remains misunderstood.
- Conditions
- Nitrous Oxide Abuse
- Being tested
- blood collection
- Keywords
- Nitrous Oxide, Neurology, Thrombosis, Biomarkers, Metabolis
- Medical subject headings
- Thrombosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
blood collectionOther
Biological analyses in the framework of care with conservation of blood samples
| Study group | Role | What they receive |
|---|---|---|
| Subjects consuming nitrous oxide with clinical outcomes | Subjects who consume nitrous oxide and who have been hospitalized in this context and who present clinical signs determined during a neurological evaluation according to the PND (Peripheral Neuropathy Disability) score or who have had a thrombotic accident related to the consumption of nitrous oxide. Receives: Other: blood collection | |
| Subjects consuming nitrous oxide without clinical outcomes | Subjects who consume nitrous oxide who do not present clinical signs related to this consumption and recruited during a routine medical consultation. Receives: Other: blood collection |
What is being measured
The primary outcome is the main question the study is designed to answer.
Blood markers related to nitrous oxide consumption
Biomarkers of cobalamin metabolism, methionine cycle and oxidative stress
Measured: through study completion an average of 1 year
Secondary outcomes (3)
Blood markers related to nitrous oxide clinical outcomes.
Biomarkers of cobalamin metabolism, methionine cycle and oxidative stress and biological markers of neurological damage.
Measured: Baseline, at 4 weeks, at 3 months and at 6 months
Estimated and self-reported nitrous oxide consumption
Measured: Baseline, at 4 weeks,and/or at 3 months and at 6 months
The severity of the clinical signs related to nitrous oxide consumption.
The severity of the signs noted during the interrogation and consultation of the patients by filling out a pre-established form listing the neurological signs (gait disorders evaluated by the PND score, presence of paresthesia and associated clinical signs (thrombotic and psychiatric events)
Measured: Baseline, at 4 weeks,and/or at 3 months and at 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Sep 2022
- Study start30 Jan 2023
- Primary completion30 Jul 2026 (estimated)
- Study completion30 Jul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Nitrous Oxide AbuseStudies of the same condition, open and under way.
- More trials run by University Hospital, LilleThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Prospective
- Enrolment
- 356 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Hospital, Lille
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05540561
- Sponsor's protocol ID
- 2021_0461
- Other IDs
- 2022-A00327-36
- Acronym
- BALON
- Status last verified
- May 2026
- First submitted
- 12 Sep 2022
- Last updated
- 19 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 19 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Biological Alterations of Laughing Gas Outcomes in Neurology
- ClinicalTrials.gov ID
- NCT05540561
- Acronym / sponsor ID
- BALON / 2021_0461
- Conditions
- Nitrous Oxide Abuse
- Keywords
- Nitrous Oxide, Neurology, Thrombosis, Biomarkers, Metabolis
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 356 participants (estimated)
- Lead sponsor
- University Hospital, LilleUniversity, hospital or other
- Study start
- 30 Jan 2023 (actual)
- Primary completion
- 30 Jul 2026 (estimated)
- Study completion
- 30 Jul 2026 (estimated)
- First posted
- 14 Sep 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
There is a toxicity linked to the chronic use of nitrous oxide, leading to neurological disorders such as combined sclerosis of the spinal cord. One thus frequently observes patients presenting disorders of walking or paresthesias, of more or less resolving evolution being able to go until the need for using a wheelchair and more recently cases of thrombosis were reported Serum or urine N2O assays are rarely performed routinely, because they do not allow to ensure a real exposure due to the very short half-life of this gas in the body. Thus, other biological monitoring markers are mentioned in the literature, such as vitamin B12 or homocysteine. Unfortunately, there are still no recommendations for biological monitoring of nitrous oxide consumption. Moreover, underlying mechanisms leading to clinical outcomes remains misunderstood.
Study design
- Observational model
- Case-control
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Subjects consuming nitrous oxide with clinical outcomes | – | Other: blood collectionSubjects who consume nitrous oxide and who have been hospitalized in this context and who present clinical signs determined during a neurological evaluation according to the PND (Peripheral Neuropathy Disability) score or who have had a thrombotic accident related to the consumption of nitrous oxide. |
| Subjects consuming nitrous oxide without clinical outcomes | – | Other: blood collectionSubjects who consume nitrous oxide who do not present clinical signs related to this consumption and recruited during a routine medical consultation. |
Who may qualify
- Ages
- 14 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Patients using or having recently used nitrous oxide, and hospitalized during the study will be offered to participate in the study.
Key inclusion criteria (6 listed)
- A current or former recreational nitrous oxide user defined
- With associated clinical signs (group 1)
- Without associated clinical signs (group 2)
- With or without clinico-biological sequelae associated with use
- Consenting to the conduct of the study
Key exclusion criteria (4 listed)
- Pregnant or breastfeeding women
- Never used nitrous oxide or stopped using it more than 6 months ago
- Lack of social security coverage
- Not willing to participate in the entire study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| blood collectionBiological analyses in the framework of care with conservation of blood samples | Other | Subjects consuming nitrous oxide with clinical outcomes, Subjects consuming nitrous oxide without clinical outcomes |
Primary outcome
Blood markers related to nitrous oxide consumption
Time frame: through study completion an average of 1 year
Biomarkers of cobalamin metabolism, methionine cycle and oxidative stress
3 secondary outcomes
Blood markers related to nitrous oxide clinical outcomes.
Time frame: Baseline, at 4 weeks, at 3 months and at 6 months
Estimated and self-reported nitrous oxide consumption
Time frame: Baseline, at 4 weeks,and/or at 3 months and at 6 months
The severity of the clinical signs related to nitrous oxide consumption.
Time frame: Baseline, at 4 weeks,and/or at 3 months and at 6 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 May 2026.
Related trials for Nitrous Oxide Abuse
RecruitingObservational study
Neurological Recovery Following NOS-SACD
Nitrous Oxide Abuse, Subacute Combined Cord Degeneration
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
8 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Nitrous Oxide Abuse, run by University Hospital, Lille at 8 sites in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 19 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 8 sites in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Guillaume Grzych, MD (0320445962 ext. +33, guillaume.grzych@chu-lille.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Blood markers related to nitrous oxide consumption (time frame: through study completion an average of 1 year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 May 2026.