This page shows what was measured, who it was measured in, and what that does not settle.
What Nitrous Oxide does in the body
Used in operating theatres, dentistry and childbirth as a fast-on, fast-off anaesthetic and painkiller. The identical gas is sold in cream-charger cartridges with no restriction, and inhaling it repeatedly destroys vitamin B12
Nitrous oxide blocks the NMDA receptor, the same target ketamine acts on, which is why it produces dissociation and analgesia and why it has been tested in depression. Its lasting harm has nothing to do with that receptor. The gas oxidises the cobalt atom at the centre of vitamin B12, and a B12 molecule that has been oxidised cannot serve the enzyme methionine synthase. Without that enzyme the body cannot make myelin properly, and the sheath on the sensory columns at the back of the spinal cord degenerates. That is a chemical reaction, not a dose-dependent toxicity in the usual sense: every exposure inactivates some B12, and repeated exposure outruns the body's ability to replace it.
What happened in people
No difference in 30-day death or cardiovascular complications with or without nitrous oxide in 7,112 at-risk surgical patients (RR 0.96, 95% CI 0.83-1.12)
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The recorded finding that sits closest to something a person would notice. Written into the record, not signed off, and it carries no population or interval.
That the week-2 HDRS separation from an air comparator in 24 patients is purely pharmacological
Where it acts
NMDA receptors throughout the central nervous system, and the cobalamin cofactor of methionine synthase in every dividing cell — the second of which is where the lasting damage happens
Kind of result
Living longer, or avoiding a major event
Supervision
Professional supervision is normally required. A regulator classifies this substance in a way that restricts how it is supplied.
What the registries record it as
The substance registry classes this as chemical.
FDA substance registry · K50XQU1029 · read 2026-08-29
The supplement label database classes it as non-nutrient/non-botanical, under the name Nitrous Oxide.
Its recorded molecular formula is N2O, weighing 44.013.
PubChem record · 948 · read 2026-08-29
Where each sentence above came from
No recorded sentence describes the change this makes in a way that stands on its own. The page opens with what it is taken for instead, and the recorded explanation follows below.
Shown as the opening line on this page.
A limit recorded against this substance. Not signed off as a reviewed claim.
The four opening statements run to 177 words.
Words this page uses
Four words worth knowing first
Chosen from what this page shows, with each one explained before the word it depends on.
Stand-in result
A stand-in result is a number measured because the real result takes too long.
A picture of it, and where the picture fails
It is like judging a journey by the speedometer rather than by arriving.
Where that stops being true. Speed does predict arrival. Many stand-in results do not predict the real one.
What people get wrong. A stand-in result is often reported as the result itself.
A surrogate endpoint substituted for a clinical endpoint, valid only where the substitution has been shown to hold.
Randomisation
Randomisation means chance decides who gets which treatment.
A picture of it, and where the picture fails
It is like a coin toss deciding the groups.
Where that stops being true. A coin toss is fair once. Fairness here comes from doing it for everyone.
What people get wrong. It is thought to make groups identical. It makes them similar on average, including on things nobody measured.
Allocation of participants to arms by a chance process, so that unmeasured factors are balanced in expectation.
Confidence interval
A confidence interval is the range the true answer is likely to sit in.
A picture of it, and where the picture fails
It is like a weather forecast giving a range rather than one number.
Where that stops being true. A forecast range covers tomorrow. This one covers what the study could resolve.
What people get wrong. The middle number is read as the answer. A range crossing zero means no change is still possible.
An interval estimate that would contain the true parameter in a stated proportion of repeated studies.
Pathway
A pathway is a chain of steps inside a cell, each one setting off the next.
A picture of it, and where the picture fails
A pathway is like a row of dominoes.
Where that stops being true. Dominoes fall one way. Pathways loop back and can switch themselves off.
What people get wrong. Changing one step is read as changing the outcome. Other steps often absorb it.
An ordered series of molecular interactions producing a defined cellular change.
What happened in people◇Read from sources, not yet reviewed
What was measured, goal by goal
One row for each goal a registered study measured something for. One column for each kind of thing that could be measured.
Registered studies list 30 outcome measures that RNAWiki could read. A registered study says what someone planned to measure. It does not say what they found. 0 of the matched studies tested this substance, and 0 posted a result.
There is no single score. A strong test result and a weak life result are different facts.
Goals down the side, kinds of measurement across the top. Each cell says what kind of thing was registered, not what was found.
Goal
Life outcome
What a body can do
How a person feels
A test result
A step in the body
Harms
How long
Who was studied
Pain
∅Nothing in the sources checkedNo registered study lists a life outcome for this goal.
∅Nothing in the sources checkedNo registered study lists a performance measure for this goal.
…Waiting for a reviewer12 registered symptom measure.
∅Nothing in the sources checkedNo registered study lists a test result for this goal.
∅Nothing in the sources checkedNo registered study lists a body-step measure for this goal.
—Not recordedHarms were not a registered measure for this goal.
—Not recordedNo finished study window is recorded.
…Waiting for a reviewerWho was studied is listed further down the page.
Mood
∅Nothing in the sources checkedNo registered study lists a life outcome for this goal.
∅Nothing in the sources checkedNo registered study lists a performance measure for this goal.
…Waiting for a reviewer5 registered symptom measure.
∅Nothing in the sources checkedNo registered study lists a test result for this goal.
∅Nothing in the sources checkedNo registered study lists a body-step measure for this goal.
—Not recordedHarms were not a registered measure for this goal.
—Not recordedNo finished study window is recorded.
…Waiting for a reviewerWho was studied is listed further down the page.
Which registered measures put each goal on this table
Pain
pain during intravesical injection; vas pain from baseline to 3 month follow up; vas pain from baseline to before 2nd block; vas pain from baseline to before 3rd block; pain scores; pain scale measurement during and after the procedure; pain scale measurement maximum pain experienced; maximum procedural pain scores
Mood
mood; montgomery asberg depression scale; total number of respiratory depression events; madrs; incidence of major postnatal depression in both groups; incidence of postnatal depression in both groups; anxiety; montgomery sberg depression rating scale
Sorted by fixed word lists, version v1. A name the rules do not recognise stays unsorted rather than moving to the nearest column.
What each mark on this table means
∅ Nothing in the sources checked
No registered study lists a life outcome for this goal.
… Waiting for a reviewer
12 registered symptom measure.
— Not recorded
Harms were not a registered measure for this goal.
What happened in people◇Read from sources, not yet reviewed
What happened in people
Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.
Composite of death, non-fatal myocardial infarction, stroke, pulmonary embolism or cardiac arrest within 30 days
✓ The study showed what it set out to show
Who was studied
NCT00430989 (ENIGMA-II, nitrous oxide in major non-cardiac surgery)
How many people
7112
Study design
Phase 4 randomised, assessor-blinded, international
Compared against
Not recorded for this study
Kind of result
Living longer, or avoiding a major event
What was found
283/3483 (8%) versus 296/3509 (8%), relative risk 0.96, 95% CI 0.83-1.12, p = 0.64
Repeated elsewhere
Failed to Replicate
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Severe nausea and vomiting was significantly higher with nitrous oxide, 15% versus 11%, p < 0.0001. Attending anaesthetists knew the allocation; patients and outcome assessors did not.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
ENIGMA (Myles et al. 2007, avoidance of nitrous oxide in major surgery)
How many people
2050
Study design
Randomised controlled trial, patient- and observer-blinded
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Median stay 7.0 versus 7.1 days, p = 0.06 (primary endpoint not met). Major complications OR 0.71, 95% CI 0.56-0.89, p = 0.003 and severe nausea and vomiting OR 0.40, 95% CI 0.31-0.51, p < 0.001, both secondary
Repeated elsewhere
Failed to Replicate
What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.
The limits of this study, and where it came from
Main limit. The headline conclusion rested on secondary endpoints; the primary endpoint of hospital stay did not separate. The comparator arm also received 80% oxygen, so the trial compared two things at once.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
Change on the 21-item Hamilton Depression Rating Scale
✓ The study showed what it set out to show
Who was studied
NCT03283670 (nitrous oxide in treatment-resistant major depression)
How many people
24
Study design
Phase 2 randomised crossover, placebo-controlled
Compared against
A dummy treatment
Kind of result
A number that stands in for health
What was found
Nitrous oxide versus placebo p = 0.01 overall; 25% versus 50% p = 0.58; 50% versus placebo -7.00 points at week 2, p = 0.001
Repeated elsewhere
Partially Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. No separation from placebo at 2 hours or 24 hours in either arm — the effect appears only at weeks 1 and 2. The comparator was air, which cannot mask a dissociative gas.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
RNAWiki holds 3 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.
What happened in people◇Read from sources, not yet reviewed
How close this is to real life
The top step is something a person would feel or care about. The bottom is a guess from software. Filled steps are where evidence exists for this substance.
□Living longer, or avoiding a major eventNo evidence recorded. Death, a heart attack, a stroke, a hospital stay.No registered study measures this.
□What a body can do day to dayNo evidence recorded. Walking, dressing, breathing, recovering.No registered study measures this.
□Measured performanceNo evidence recorded. How much was lifted, how far was run, how fast.No registered study measures this.
■Symptoms and quality of lifeEvidence recorded. Pain, tiredness, mood, sleep, as the person rated it.17 registered measures of this kind.
■A number that stands in for healthEvidence recorded. Cholesterol, blood sugar, bone density. A stand-in, not the thing itself.3 registered measures of this kind.
■A step measured inside a personEvidence recorded. Something measured in human tissue or human cells.A human record sits on the stored organism ladder.
■AnimalsEvidence recorded. Mice, rats, dogs. Useful for ideas, not proof about people.Stored records in Mouse, Rat, Dog. A result in animals says what to test next. It does not say what happens in people.
■Cells in a dishEvidence recorded. Cells or chemistry on a bench, far from a whole body.Stored mechanism abstracts describe steps measured in cells or tissue.
□A guess from softwareNo evidence recorded. Nobody measured it. RNAWiki never publishes one as a finding.RNAWiki stores no prediction for this record. Software can suggest a link. RNAWiki does not publish one as a finding.
Higher on these steps means closer to something a person would feel. It does not mean better done.
What it changes in the body◇Read from sources, not yet reviewed
The path through the body
From what a person takes to what changes. A solid line is a step measured in people. A dashed line is a step nobody has measured that way.
Start
Nitrous Oxide
What a person takes: Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge.
The measurement behind this step
Medical delivery is from a calibrated flowmeter or, for Entonox, a 50:50 fixed mixture through a demand valve the patient triggers themselves, which limits over-delivery by design. Non-medical delivery is from 8-gram cream chargers or, increasingly, large catering cylinders, discharged into a balloon and inhaled — a route with no oxygen mixed in and no upper limit on repetition.
Getting in
Breathed in as a gas
It goes straight from the lungs into the blood. Effects begin within a couple of breaths and end within a couple of minutes of stopping.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Inspired concentrations of 50% to 70% in anaesthesia, 50% in Entonox, and 25% or 50% for one hour in the depression trials. Low blood-gas solubility gives very rapid equilibration and equally rapid washout, and almost no metabolism — the gas is exhaled essentially unchanged.
A small uncharged gas crosses into the brain immediately. There is no transporter and no delay.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Free diffusion across the blood-brain barrier. Because it is not metabolised, the brain concentration tracks the inspired concentration almost in real time, which is what makes titration during a procedure possible and what makes recovery immediate.
It sits in the same glutamate receptor ketamine blocks, producing analgesia and dissociation.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Non-competitive NMDA-receptor antagonism, with endogenous opioid mechanisms contributing to analgesia. In rodent brain the same action is both neuroprotective against excitotoxicity and, at anaesthetic exposures, neurotoxic to specific cortical neurons.
Separately and permanently, it reacts with vitamin B12 and inactivates it. This has nothing to do with the receptor and does not wear off when the gas is exhaled.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Irreversible oxidation of cob(I)alamin inactivates methionine synthase, raising homocysteine, trapping folate as 5-methyltetrahydrofolate and reducing S-adenosylmethionine-dependent methylation. The biochemical signal appears after a single long anaesthetic and accumulates with repeated exposure.
Which, with enough exposure, degenerates the spinal cord
The sensory columns at the back of the spinal cord lose their myelin. Numbness and unsteadiness follow, and vitamin B12 treatment fully reverses it in about a quarter of reported cases.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Subacute combined degeneration of the dorsal and lateral columns with an axonal sensorimotor peripheral neuropathy. In 59 pooled adolescent cases, MRI posterior-column change in 89%, neuropathy on nerve conduction in 88%, raised homocysteine or methylmalonic acid in 92% against low B12 in only 45%, and 27% full recovery with 61% improvement on B12 treatment.
No suggested links are held for this record, so nothing is hidden from this path.
What we know
The record describes 5 steps from taking it to an effect in a person.
How we know it
Each step names the study behind it in the technical detail beside it.
What this does not prove
A change inside the body is a reason to look. It is not a result in a person.
Why it matters
A reader can see exactly where the chain stops being measured in people.
What we still do not know
No reviewed claim binds any of these steps to a named population.
What it would be like to take◇Read from sources, not yet reviewed
Felt, measured, or meaningful
Three different things that get called the same word. Registered studies measured all three, and mixing them is how a blood test becomes a health claim.
Felt
Things a person could notice without a test.
mood
pain during intravesical injection
vas pain from baseline to 3 month follow up
vas pain from baseline to before 2nd block
vas pain from baseline to before 3rd block
pain scores
pain scale measurement during and after the procedure
pain scale measurement maximum pain experienced
montgomery asberg depression scale
maximum procedural pain scores
and 7 more.
Measured
Things only a test, a scale or a device shows.
plasma total homocysteine concentration
plasma concentration of cytokines
heart rate
Meaningful
Things that change how a life goes, not only a number.
No registered study measured anything of this kind.
A registered study says what someone planned to measure. It does not say what they found. A number moving is not the same as a life going better. The two are shown apart here.
Felt, but not shown to help. A person notices a change. No study showed it leads anywhere good.
Measured, but not felt. A number moves. The person notices nothing. Both can be true.
Measured, but not shown to matter. A number moves in the good direction. Nobody showed that lives went better.
Matters, but takes years. The result that counts may take longer than anyone would keep watching.
Names that fit none of the three (10)
hyperalgesia
systemic vascular resistance index
count of live and dead target erythroleukemic cells
total number of respiratory depression events
adverse events
incidence of major postnatal depression in both groups
incidence of postnatal depression in both groups
reaction time
intersegmental border appearance time during the surgery
satisfaction
These are harms, study-process measures, or names the rules did not recognise. They are shown rather than dropped.
What is missing or unclear◇Read from sources, not yet reviewed
Were people like you studied?
RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.
Who was studied
People similar to this profile were included.
Surgical and dental patients, women in labour, and — in the case series — adolescents and young adults inhaling from cartridges or tanks over weeks to months.
Who is missing from the studies
Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
Where the result stopped carrying
ENIGMA missed its own primary endpoint of hospital stay and drew its conclusion from secondary endpoints; the major-complication finding did not survive a trial three times larger
Neither depression trial arm separated from placebo at 2 or 24 hours, despite the acute drug effect being unmistakable at those timepoints
This is a scope explorer, not a diagnosis engine.
It shows who was studied so you can see whether people similar to you were included.
RNAWiki cannot tell whether a study fits you. It can show who was in it.
What it would be like to take◇Read from sources, not yet reviewed
Why it might seem to do nothing
A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.
It was studied for a different goal
The studies measured something else entirely.
On this record: Some registered studies measured things that match no goal on this page.
It was studied in different people
The people in the studies were not much like the reader.
On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
The evidence may simply be wrong
Small early studies often do not hold up.
On this record: RNAWiki has not yet published a reviewed conclusion for this use.
Other reasons RNAWiki checked and found nothing for (10)
A different form was studied
The studied form is not the form on the shelf. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.
None of these is a reason to take more. Taking more is not a step this page ever suggests.
What it would be like to take◇Read from sources, not yet reviewed
What taking it involves
The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.
How it is supplied
Prescription only
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
Read from the recorded approval status.
No source is stored against this line.
Form and route
Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form and route recorded on this substance.
No source is stored against this line.
Who oversees it
Professional supervision is normally required. A regulator classifies this substance in a way that restricts how it is supplied.
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
Suppression classes recorded: S1.
No source is stored against this line.
What is in the pack
Medical delivery is from a calibrated flowmeter or, for Entonox, a 50:50 fixed mixture through a demand valve the patient triggers themselves, which limits over-delivery by design.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on how this is sold. The rest of the recorded wording: Non-medical delivery is from 8-gram cream chargers or, increasingly, large catering cylinders, discharged into a balloon and inhaled — a route with no oxygen mixed in and no upper limit on repetition.
No source is stored against this line.
Where it is registered
Regulatory records are listed in the technical disclosure at the foot of this page.
# Counted from records
Where this came from
A count of rows RNAWiki holds. It describes our records, not your body.
Register entries are stored per jurisdiction and shown with their dates.
No source is stored against this line.
Why people stop
Not recorded.
∅ Nothing recorded
Where this came from
RNAWiki holds nothing here and says so rather than guessing.
No record of why people stopped taking it is stored for this substance.
No source is stored against this line.
What it would be like to take◇Read from sources, not yet reviewed
What can go wrong
Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.
·Worth asking a clinician aboutWritten into the record from the studies named on this page
Acute risks are hypoxia when the gas is inhaled without added oxygen, and expansion of any closed gas space — bowel, middle ear, pneumothorax — because nitrous oxide diffuses into such spaces faster than nitrogen leaves. Nausea and vomiting is the commonest adverse effect in both large surgical trials. The cumulative risk is cobalamin oxidation with methionine synthase inactivation, producing subacute combined degeneration of the spinal cord and peripheral neuropathy; in the pooled adolescent series only 27% recovered fully with B12 treatment. Cold injury from rapidly expanding gas leaving a cylinder is a documented additional hazard of large-cylinder use. Occupational exposure of theatre and dental staff is controlled by scavenging systems for the same cobalamin reason.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
These are reports people sent to a regulator. They do not show the medicine caused the reaction.
Nobody counted how many people took the medicine and reported nothing.
The same event can be reported more than once, and many reports are incomplete.
News coverage, lawsuits and new warnings change how often people report.
A count is not a rate and not a risk.
Nitrous Oxide appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 336 reaction mentions were counted. One report can name several reactions.
open-targets-adr · recorded 2026-06-24 · a recorded source, not a stored snapshot
Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.
Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
What is missing or unclear◇Read from sources, not yet reviewed
Does the exact form matter?
Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.
The form that was studied
Inhaled gas, from an anaesthetic machine, a demand valve, or an unregulated cartridge
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form used in the studies cited on this page.
No source is stored against this line.
What is sold
A recorded note compares this form with the others that are sold. It is kept below, word for word.
§ A fixed RNAWiki sentence
Where this came from
Wording RNAWiki always uses, not a finding about this substance.
The recorded note, unchanged: Non-medical delivery is from 8-gram cream chargers or, increasingly, large catering cylinders, discharged into a balloon and inhaled — a route with no oxygen mixed in and no upper limit on repetition.
No source is stored against this line.
What is recorded as being sold
49 products list this as an active ingredient in the United States drug directory. 45 of them contain it and nothing else.
FDA National Drug Code directory · 72343-001 · read 2026-08-29
They are sold as gas and liquid, taken oral and respiratory (inhalation).
FDA National Drug Code directory · 72343-001 · read 2026-08-29
49 published labels name it as an active ingredient. 45 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 25dd7dca-2cfd-1e1c-e063-6294a90ad238 · read 2026-08-29
Those labels are classed as human otc drug and human prescription drug.
US prescribing information · 25dd7dca-2cfd-1e1c-e063-6294a90ad238 · read 2026-08-29
4667 marketed supplement labels list this ingredient, classed as mineral, non-nutrient/non-botanical and other combinations.
Those labels carry all other, nutrient and structure/function claims. A claim of that kind is written by the manufacturer and is not assessed by any regulator, so its presence says nothing about whether it is true.
Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.
What it would be like to take◇Read from sources, not yet reviewed
What you could measure
This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.
Self-experiment planning is not offered for a prescription or clinician-supervised medicine. The questions below are for a clinician or pharmacist.
Questions worth asking
Which of the trials of Nitrous Oxide studied people like me?
What was measured, and for how long?
Was the result a laboratory value or a health outcome?
What would we watch for, and when would we stop?
Tracking can show whether something changed for you. It cannot show what caused it.
RNAWiki records evidence. It does not say whether this substance is right for you.
What is missing or unclear◇Read from sources, not yet reviewed
Claims that go past the evidence
Things said about this substance that sound reasonable, and the exact step that is missing between the evidence and the claim.
✗Goes past the evidence
That the week-2 HDRS separation from an air comparator in 24 patients is purely pharmacological
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That a normal serum B12 excludes nitrous-oxide neurotoxicity — it was normal in 55% of the adolescent series
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That rodent NMDA-antagonist neurotoxicity at anaesthetic exposures corresponds to human injury; that has not been shown
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That unrestricted legal availability implies established safety of repeated inhalation
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
What is missing or unclear◇Read from sources, not yet reviewed
What nobody knows yet
Open questions, each with why it is open and what would close it.
How fast does the body clear it?
The sources RNAWiki checked hold nothing for this field.
Why it matters. Without this, nothing on this page can say how long anything lasts.
What would answer it
A stored source that records it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing populations
Which groups were under-represented in the studies has not been recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing long-term data
No completed tested study window is recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
No reviewed conclusion
RNAWiki has not yet published a reviewed conclusion for this use.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing interaction studies
No interaction was found in the registers checked. Not finding one is not the same as showing there is none.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Formulation uncertainty
Several salts, forms or products of Nitrous Oxide are recorded. Results from one form may not transfer to another.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Mechanism not reviewed
No reviewed mechanism story exists for this substance.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
What happened in people◇Read from sources, not yet reviewed
Check any of this yourself
Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.
Every line above can be traced to the study named beside it. Follow the link and read it.
One trial said avoid it, a trial three times larger said it is safe
In plain words
A 2,050-patient trial found fewer complications when nitrous oxide was left out of the anaesthetic, and concluded routine use should be questioned. A 7,112-patient trial designed to test that found no difference at all in death or cardiovascular events.
What was measured
Composite of death and cardiovascular complications at 30 days, 7,112 randomised, versus major-complication rate in the 2,050-patient predecessor
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
ENIGMA (Myles et al. 2007) randomised 2,050 patients having major surgery to nitrous-oxide-free (80% oxygen, 20% nitrogen) or nitrous-oxide-based (70% N2O, 30% oxygen) anaesthesia. The nitrous-oxide-free group had significantly lower rates of major complications (OR 0.71, 95% CI 0.56-0.89, p = 0.003) and severe nausea and vomiting (OR 0.40, 95% CI 0.31-0.51, p < 0.001), though median hospital stay did not differ (7.0 vs 7.1 days, p = 0.06). The authors concluded routine use should be questioned. ENIGMA-II (Myles et al. 2014) then randomised 7,112 patients aged 45 or over with known or suspected coronary artery disease having major non-cardiac surgery. The primary composite of death, non-fatal myocardial infarction, stroke, pulmonary embolism or cardiac arrest within 30 days occurred in 283 of 3,483 (8%) with nitrous oxide and 296 of 3,509 (8%) without: relative risk 0.96, 95% CI 0.83-1.12, p = 0.64. Surgical site infection did not differ (9% vs 9%, p = 0.61). Severe nausea and vomiting was higher with nitrous oxide (15% vs 11%, p < 0.0001), replicating the one ENIGMA finding that held. The two trials differed in comparator oxygen concentration as well as in size, which is part of why the first result did not reproduce.
Written into the record, not signed off as a reviewed claim
It destroys vitamin B12 by chemistry, not by dose-dependent toxicity
In plain words
Nitrous oxide oxidises the cobalt atom at the centre of vitamin B12. An oxidised B12 cannot run the enzyme that maintains myelin, so the sensory columns at the back of the spinal cord degenerate.
What was measured
Methionine synthase inactivation via cobalamin oxidation, with plasma homocysteine and methylmalonic acid as the clinical markers
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Nitrous oxide irreversibly oxidises the cobalt centre of cob(I)alamin, inactivating methionine synthase, the enzyme that converts homocysteine to methionine using 5-methyltetrahydrofolate as the methyl donor. The consequences are measurable within a single long anaesthetic — plasma homocysteine rises — and cumulative with repeated exposure. Downstream, folate is trapped as 5-methyltetrahydrofolate, S-adenosylmethionine-dependent methylation of myelin basic protein falls, and subacute combined degeneration of the dorsal and lateral columns follows. ENIGMA's authors flagged the B12, folate and DNA-synthesis interference in 2007 while noting the clinical consequences were unclear; the recreational case series since have made them clear. This is a stoichiometric chemical reaction with a cofactor rather than a receptor interaction, which is why a single dental exposure is harmless and daily cartridge use is not.
Written into the record, not signed off as a reviewed claim
Fifty-nine adolescents: posterior-column MRI change in 89%, full recovery in 27%
In plain words
Pooling new cases with everything published, 59 teenagers with nerve damage from inhaling nitrous oxide were reviewed. Nearly nine in ten had visible spinal-cord changes on MRI. With B12 treatment, most improved but only about a quarter recovered fully.
What was measured
MRI posterior-column involvement, nerve conduction findings, biochemical markers and recovery rate in 59 adolescents
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Cohen-Vig et al. combined five new adolescent cases admitted to three tertiary centres in 2024 with 54 cases from a systematic review of Embase, MEDLINE, Scopus and PubMed covering 2011 to 2026 — 59 patients aged 14 to 18 in total. All presented with neurological complaints, predominantly sensory. Vitamin B12 was low in 45%, but elevated homocysteine or methylmalonic acid was present in 92%, so a normal B12 does not exclude the diagnosis. MRI showed long posterior-column changes in 89% and nerve conduction studies showed a predominantly axonal sensorimotor peripheral neuropathy in 88%. Intracranial pressure was raised in two of the new patients. With B12 treatment, 27% recovered and 61% improved — meaning roughly one in eight did neither, and a majority of those who improved retained deficits.
Written into the record, not signed off as a reviewed claim
A quarter-strength dose works as well as a half-strength one in depression
In plain words
Twenty-four people with severe treatment-resistant depression breathed 25% nitrous oxide, 50% nitrous oxide, or air, an hour each on separate occasions. Both concentrations beat air, neither beat the other, and side effects fell sharply at the lower one.
What was measured
HDRS-21 change at 2 hours, 24 hours, 1 week and 2 weeks, crossover, n=24
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Nagele et al. ran a phase 2 crossover trial (NCT03283670) in 24 patients with severe treatment-resistant major depression, each receiving a single one-hour inhalation of 50% nitrous oxide, 25% nitrous oxide, and placebo (air/oxygen), in randomised order. The primary outcome was change on the 21-item Hamilton Depression Rating Scale. Nitrous oxide improved symptoms versus placebo overall (p = 0.01) with no difference between 25% and 50% (p = 0.58). Against placebo, 25% gave -0.75 points at 2 hours (p = 0.73), -1.41 at 24 hours (p = 0.52), -4.35 at week 1 (p = 0.05) and -5.19 at week 2 (p = 0.02); 50% gave -0.87 at 2 hours (p = 0.69), -1.93 at 24 hours (p = 0.37), -2.44 at week 1 (p = 0.25) and -7.00 at week 2 (p = 0.001). Adverse events declined substantially with dose (p < 0.001). The pattern worth noting is that nothing separated at 2 or 24 hours — the separation appears at one and two weeks, long after the gas has gone.
Written into the record, not signed off as a reviewed claim
A one-hour inhalation of a dissociative gas is not a blindable comparison
In plain words
The depression trials compared nitrous oxide with air. Anyone breathing nitrous oxide for an hour knows it, and so does the person watching.
What was measured
That the week-1 and week-2 HDRS separation from an air comparator is a pharmacological antidepressant effect rather than a pharmacological effect plus expectancy
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Both the 2015 proof-of-concept crossover and the 2021 phase 2 used air/oxygen as the comparator. Nitrous oxide at 25% or 50% produces immediate, unmistakable dissociation, euphoria and altered proprioception; the placebo produces nothing. That the treatment periods are separated by weeks and the outcome is measured at one and two weeks mitigates but does not remove the expectancy contribution, because the participant rates their own mood knowing which sessions were active. The trial's own most useful internal control is the null contrast between 25% and 50%: if intensity of the acute experience drove the antidepressant rating, the stronger dose should have scored better, and it did not. That comparison is the strongest argument against a purely expectancy account, and it is an argument rather than a measurement.
Written into the record, not signed off as a reviewed claim
It is not a controlled substance anywhere in the federal schedules
In plain words
Nitrous oxide does not appear in any US drug schedule. It is a prescription medical gas on one hand and an unrestricted food-grade propellant on the other, and the two are the same molecule.
What was measured
Absence from all five federal schedules alongside active prescription medical-gas approvals
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Nitrous oxide appears nowhere in 21 CFR part 1308, Schedules I through V. Its medical use runs through prescription medical-gas applications approved by FDA — Nitrous Oxide USP under NDA 205704 (Air Liquide, June 2013) and several others — which came out of the medical-gas provisions of the FDA Safety and Innovation Act. Its non-medical availability runs through food-grade cartridges sold as whipped-cream propellant with no scheduling restriction. The result is a substance for which the same chemical is simultaneously a prescription drug, an industrial gas and a grocery item, distinguished only by the label on the cylinder. This record notes it as a measured regulatory fact because readers frequently assume that unrestricted availability implies an established absence of harm, and the myeloneuropathy series show it does not.
Source
21 CFR part 1308, current eCFR text; Drugs@FDA NDA 205704 (Nitrous Oxide USP, approved 16 June 2013)
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
Both neuroprotective and neurotoxic, in the same 1998 paper
In plain words
The study that identified nitrous oxide as an NMDA blocker also showed it could damage neurons in rat brain, in the same way other NMDA blockers do. Both findings were published together.
What was measured
NMDA-receptor antagonism with both neuroprotective and neurotoxic effects in rodent brain
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Jevtović-Todorović et al. established that nitrous oxide acts as a non-competitive NMDA-receptor antagonist and reported, in the same paper, both neuroprotective and neurotoxic consequences of that action — the pattern already known for ketamine and MK-801, in which NMDA blockade protects neurons against excitotoxic injury while producing vacuolar injury in specific cortical neurons. The finding matters here for two reasons: it is the mechanistic basis for testing the gas in depression alongside ketamine, and it means the NMDA action and the cobalamin action are two independent hazards with different time courses. The neurotoxic findings are rodent data at anaesthetic exposures and have not been shown to correspond to human injury.
Written into the record, not signed off as a reviewed claim
Where else this substance is registered
FDA substance identifier (UNII)
K50XQU1029
CAS registry number
10024-97-2
PubChem compound
948
ChEMBL
CHEMBL1234579
ChEBI
17045
RxNorm concept
7486
EMA substance identifier
100000092168
European Chemicals Agency number
233-032-0
DrugBank
DB06690
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Every public sentence names a source
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Trial roles classified for highlighted evidence
No registered study is classified as testing this substance.
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Safety mode resolved
Suppression classes recorded: S1.
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Canonical metadata present
slug and display name present
What is missing or unclear◇Read from sources, not yet reviewed
How this medicine reached us
Kept near the foot of the page. A historical event moves up only when it changes something about this substance today.
What the approval register records
6 approved applications cover products containing this substance. The earliest was NDA205704, approved 20130616 to AIR LIQUIDE AMERICA SPECIALITY GASES.
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What is not here
4 questions this page could not answer
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How long anything takes — found nothing in the sources checked.
What it may clash with — found nothing in the sources checked.
Other ways to the same goal — found nothing in the sources checked.
What changed on this page — found nothing in the sources checked.
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Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.
The older medicine-wide conclusion held in this record
Written for a clinical reader, and about the medicine as a whole rather than about one indication, population and set of trials. RNAWiki does not treat it as a programme conclusion and no reviewer has signed it off in that form. It is here word for word because it is what the record holds.
A 7,112-patient randomised trial found no increase in death or cardiovascular complications from adding it to anaesthesia, overturning a smaller trial that had; and the same molecule, inhaled repeatedly from unrestricted cartridges, irreversibly oxidises vitamin B12 and produces a myeloneuropathy with posterior-column changes on MRI in 89% of reported adolescent cases.
Recorded evidence blocks (11)
Q2
What did Nitrous Oxide's largest trial (7112 people) and its longest (12 years) measure?
7112 people in Nitrous Oxide's largest registered study, 12 years in its longest registered window, measuring EEG index value during three concentrations of nitrous oxide. ClinicalTrials.gov · 2026-09-01
27 na, 23 phase4, 17 phase2, 10 phase3, 7 early phase1, 6 phase1, 2 na or unstated; NCT01622322; 2023-12; no ageing endpoint recorded. Last human test completed 2026, NCT06702631.
Interpretation These counts include studies where Nitrous Oxide was a comparison treatment, a background treatment or an exposure in an observational study, and the longest window may be a planned end date. Trial roles have not yet been classified for this record.
Show the evidence
na
27
phase4
23
phase2
17
phase3
10
early phase1
7
phase1
6
2 more recorded rows
na or unstated
2
Last recorded human testNCT06702631
2026-06-30
recorded 2026-09-01 · last checked 2026-09-04
Q3
From mouse to human: where has Nitrous Oxide shown lifespan?
futility/efficacy (1), accrual/recruitment (5), sponsor decision unspecified (1) and other (9): Nitrous Oxide's stop wording, clustered. ClinicalTrials.gov · 2026-09-01
"unknown - no record of study conduct in departmental archive"; 16 of 91 registered studies
Show the evidence
Trial
NCT00250692
withdrawn; "unknown - no record of study conduct in departmental archive"
NCT01622322
withdrawn; "no enrollment"
NCT01622335
withdrawn; "Study was terminated per Principal Investigator decision."
NCT01744184
terminated; "Resource issues, Poor recruitment"
NCT02351869
terminated; "This study was terminated due to COVID-19 pandemic-related halting of recruitment in the context of an upcoming replacement of the study MRI scanner."
2 recorded entries; human; also "Nitrous oxide 50.0% +/- 2.0%", "50 % Nitrous Oxide plus 50% Oxygen"
Show the evidence
human
NCT01744184
Nitrous oxide 50.0% +/- 2.0%
NCT03879538
50 % Nitrous Oxide plus 50% Oxygen
recorded 2026-09-01 · last checked 2026-09-04
Q6
More Nitrous Oxide was worse in human: at what point?
U-shaped in human: "Specifically, meat consumption (except for beef) has a U-shaped relationship with carbon emissions and an inverted U-shaped relationship with methane and nitrous oxide emissions." Europe PMC · dose-response search · 2020-10-29
1 recorded sentence naming Nitrous Oxide; U-shaped
Show the evidence
U-shapedPMID 33118073
"Specifically, meat consumption (except for beef) has a U-shaped relationship with carbon emissions and an inverted U-shaped relationship with methane and nitrous oxide emissions."
recorded 2020-10-29 · last checked 2026-09-04
Q7
Which of adverse events, anxiety and count of live and dead target erythroleukemic cells did Nitrous Oxide's trials measure?
adverse events, anxiety and count of live and dead target erythroleukemic cells lead 30 outcome terms across Nitrous Oxide's trials. ClinicalTrials.gov · 2026-09-01
vas pain from baseline to 3 month follow up, vas pain from baseline to before 2nd block, vas pain from baseline to before 3rd block, hyperalgesia, systemic vascular resistance index and pain scores follow.
Show the evidence
mood
1
plasma total homocysteine concentration
1
pain during intravesical injection
1
vas pain from baseline to 3 month follow up
1
vas pain from baseline to before 2nd block
1
vas pain from baseline to before 3rd block
1
14 more recorded rows
hyperalgesia
1
systemic vascular resistance index
1
pain scores
1
pain scale measurement during and after the procedure
1
pain scale measurement maximum pain experienced
1
count of live and dead target erythroleukemic cells
1
plasma concentration of cytokines
1
montgomery asberg depression scale
1
maximum procedural pain scores
1
total number of respiratory depression events
1
visual analog pain assessment scale
1
madrs
1
pain intensity
1
adverse events
1
recorded 2026-09-01 · last checked 2026-09-04
Q8
Which of Nitrous Oxide's 12 ongoing trials reports first?
Comparison of functional connectivity between default mode network of treatment-resistant depressed and non-depressed participants; The incidence of major postnatal depression in both groups; latest 2030-05-01
Show the evidence
Trial
NCT02994433
"NMDA Receptor Antagonist Nitrous Oxide Targets Affective Brain Circuits"; n 60; "Comparison of functional connectivity between default mode network of treatment-resistant depressed and non-depressed participants"; 2027-04-30
NCT03167905
"CODEPAD (Collaborative Outcomes of DEpression and Pain Associated With Delivery)"; n 881; "The incidence of major postnatal depression in both groups"; 2027-12-31
NCT03736538
"Nitrous Oxide- Suicidal Ideation"; n 50; "Severity and number of adverse events in both nitrous oxide and placebo groups"; 2026-12
NCT03826693
"Efficacy of Nitrous Oxide in OCD: Pilot Study"; n 45; "Improvement in the severity of OCD symptoms as measured by the Yale-Brown Obsessive Compulsive Scale (YBOCS)"; 2027-10
NCT05383495
"Anxiolysis for Laceration Repair in Children"; n 300; "Observational Scale of Behavioral Distress - Revised (OSBD-R)"; 2026-12-31
NCT05895383
"Self-Adjusted Nitrous Oxide: A Feasibility Study in the Setting of Vasectomy"; n 35; "Procedural pain assessed by the Visual Analog Scale for Pain (VAS-P)"; 2027-01-30
6 further recorded trials
NCT06118567
"Effect of Nitrous Oxide on Aggression."; n 50; "Cortico-Limbic Response to Anger Faces"; 2027-08-31
NCT06382389
"Efficacy of EMONO as an add-on Therapy to Conventional Antidepressants for the Treatment of Depressive Symptoms in Nursing-home Residents With Neurocognitive Disorders: a Randomized Controlled Trial-"; n 96; "Changes in the CORNELL depression severitý scale between S4 (one week after the last administration of MEOPA or medical air) and S1 (baseline)."; 2028-09
NCT06557642
"Nitrous Oxide and EMOtional Cognition"; n 88; "Changes in Emotional Ratings of Personal Memories (Memory Reconsolidation)"; 2025-10-01
NCT07245628
"A Trial of Self-Adjusted Nitrous Versus Placebo During Office Vasectomy"; n 50; "Mean Difference in VAS-A During Vasectomy Procedure and S-PCS Immediately After Vasectomy Procedure, Comparing Participants Receiving and Not Receiving Self-Administered Low Dose Nitrous Oxide"; 2030-05-01
NCT07262008
"Sustained Mood Improvement With Laughing Gas Exposure"; n 120; "Change in Montgomery-Åsberg Depression Rating Scale (MADRS) score"; 2028-09-01
NCT07387315
"A Randomized, Placebo-controlled Trial of Nitrous Oxide During In-office Bladder Botox Injections"; n 96; "Overall Pain (10-point NRS)"; 2026-12
recorded 2026-09-01 · last checked 2026-09-04
Q9
Which 31 trials of Nitrous Oxide posted no result?
Posted no result
31 of 31 completed trials
Registrations
NCT00000255, NCT00000260, NCT00164047, NCT00226837, NCT00146250 and NCT00482456, and 25 more
Completion dates
oldest 1996-05; newest 2024-06-10
Show the evidence
Trial
NCT00000255
1996-05
NCT00000260
1998-01
NCT00164047
2004-12
NCT00226837
2005-08
NCT00146250
2005-09-30
NCT00482456
2007-03
14 further recorded trials
NCT00781352
2007-03
NCT00318825
2008-09
NCT02671578
2008-11
NCT00547209
2009-11
NCT00948103
2011-12
NCT01581450
2012-04
NCT01735669
2014-01
NCT01865721
2014-04
NCT01287052
2015-01
NCT03165500
2017-05-04
NCT04050267
2019-04-29
NCT02783508
2019-05
NCT04124562
2019-11-15
NCT03807297
2019-12-30
Q10
At the median, Nitrous Oxide's trials enrolled 50 people — anything larger?
Median enrolment
50
Largest enrolment
7112
Registered trials counted
91
Q11
What do 336 spontaneous reports say about Nitrous Oxide — and not say?
These are reports people sent to a regulator. They do not show the medicine caused the reaction. Nobody counted how many people took the medicine and reported nothing. The same event can be reported more than once, and many reports are incomplete. News coverage, lawsuits and new warnings change how often people report. A count is not a rate and not a risk.
Nitrous Oxide appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 336 reaction mentions were counted: drug abuse 74; subacute combined cord degeneration 66; choroidal infarction 31; vitamin b12 deficiency 30. open-targets-adr · CHEMBL1234579 · 2026-06-24
Show the evidence
drug abuse
74
subacute combined cord degeneration
66
choroidal infarction
31
vitamin b12 deficiency
30
myelopathy
27
paraesthesia
27
4 more recorded rows
anaesthetic complication neurological
25
substance use
20
pulmonary oedema
19
bradycardia
17
recorded 2026-06-24 · last checked 2026-09-04
Q12
What is recorded about Nitrous Oxide and NAD+?
"However, Nampt activators could reduce the apoptosis of hippocampal primary cells in vitro after 4 hours exposed with Sev-N<sub>2</sub>O. Thus, we believed that down-regulation of Nampt/RelB signaling was closely related to neuronal apoptosis in the hippocampus contributed to the neurotoxicity and cognitive dysfunction induced by general…" — where Nitrous Oxide and NAD+ appear together. Europe PMC · pathway abstract search · 2018-01-01
NAD+; PMID 31938112, 23683698
Show the evidence
NAD+
PMID 31938112
"However, Nampt activators could reduce the apoptosis of hippocampal primary cells in vitro after 4 hours exposed with Sev-N<sub>2</sub>O. Thus, we believed that down-regulation of Nampt/RelB signaling was closely related to neuronal apoptosis in the hippocampus contributed to the neurotoxicity and cognitive dysfunction induced by general anesthesia with sevoflurane-nitrous oxide."
PMID 23683698
"The 160mg/L sulfide up-regulated or specifically expressed succinate dehydrogenase, iron-sulfur protein, oxidoreductase, serine hydroxymethyltransferase, and iron superoxide dismutase for sulfide metabolism, 2-oxoglutarate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, NAD(+)-dependent aldehyde dehydrogenase, malate dehydrogenase and succinate dehydrogenase for carbon metabolism, and…"
recorded 2018-01-01 · last checked 2026-09-04
Where it is registeredIdentifiers, relations and other names
Dinitrogenii oxidum, Dinitrogen monoxide, Dinitrogen oxide, Factitious air, Laughing gas, Nitrogen oxide (n(sub 2)o), Nitrogen protoxide, Nitrogenum oxygenatum, Protoxide of nitrogen, emono, equimolar mixture of oxygen and nitrous oxide, kalinox
Development code
E-942, FEMA NO. 2779, INS-942, INS NO.942
Trade name
Entonox
Salt form
Nitrous Oxide USP, approved as a prescription medical gas under several NDAs including NDA 205704 (2013). Entonox is the 50:50 nitrous oxide / oxygen mixture used for labour and procedural analgesia
Sources (9)
Sources
ClinicalTrials.govclinicaltrials.gov ·
ClinicalTrials.govClinicalTrials.gov API v2 snapshot 2026-09-01T09:00:05 ·
ChEMBL ATC CC BY-SA · ClinicalTrials.gov — US Government work · Europe PMC — metadata only, under the recorded legal gate · Open Targets 26.06 — CC0 · derived from this page's own recorded fields; no external licence · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md
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✓ source coverage passed: 9 source rows
✓ no critical contamination: no quarantine open
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