Mesuximide
- Prescription medicine
- Prescription only
- Identity checked
- Sources last checked 2026-09-04
This page shows what was measured, who it was measured in, and what that does not settle.
What Mesuximide does in the body
Absence (petit mal) seizures that are refractory to other drugs
From the FDA-approved label: Methsuximide suppresses the paroxysmal three cycle per second spike and wave activity associated with lapses of consciousness which is common in absence (petit mal) seizures. The frequency of epileptiform attacks is reduced, apparently by depression of the motor cortex and elevation of the threshold of the central nervous system to convulsive stimuli.
What happened in people
RNAWiki has not yet published a reviewed conclusion for this use.
A fixed RNAWiki sentence
Where this came from
Wording RNAWiki always uses, not a finding about this substance.
No reviewed claim names a result for any goal on this record.
No source is stored against this line.
The limit that matters most
Not recorded.
- Where it acts
- Not recorded.
- Kind of result
- No result is published, so no kind of result applies yet
- Supervision
- RNAWiki has not recorded a supervision or regulatory status for this substance.
What the registries record it as
The substance registry classes this as chemical.
FDA substance registry · 0G76K8X6C0 · 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.
No statement of the main limit is recorded.
The four opening statements run to 79 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.
Biomarker
A biomarker is a number from a test that stands in for something about health.
A picture of it, and where the picture fails
A biomarker is like a fuel gauge.
Where that stops being true. A gauge is wired to the tank. Many biomarkers are only loosely tied to health.
What people get wrong. A better number is read as a better life. Several medicines improved a number and helped nobody.
A measurable indicator used as a substitute for a clinical outcome of interest.
Placebo
A placebo is a dummy treatment given so the real one can be compared with it.
A picture of it, and where the picture fails
A placebo is like a blank control in an experiment.
Where that stops being true. A blank does nothing. People given a placebo often do get better.
What people get wrong. A placebo effect is read as imaginary. The improvement is measured and real.
An inactive intervention matched in appearance to the test intervention, used to control for non-specific effects.
Comparator
A comparator is whatever the treatment was measured against.
A picture of it, and where the picture fails
It is like the other runner in a race.
Where that stops being true. A race has one winner. A study can show both arms improved.
What people get wrong. Results are read without asking what the other group got. Beating nothing is not beating a treatment.
The control condition against which the experimental intervention is assessed.
What is missing or unclearRead 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.
- & USAGE Methsuximide is indicated for the control of absence (petit mal) seizures that are refractory to other drugs.
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.
What the label states about particular groups
On people who are pregnant, the label states: “To provide information regarding the effects of in utero exposure to methsuximide, physicians are advised to recommend that pregnant patients taking methsuximide enroll in the (NAAED) Pregnancy Registry.”
US prescribing information · 5138e347-665b-4dd6-b9f8-12f4a807ed4e · read 2026-08-30
Where the result stopped carrying
- 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 takeRead 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.
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.
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 (11)
- It was studied for a different goal
- The studies measured something else entirely. Nothing in this record points to this reason.
- 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 takeRead 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
Oral
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
RNAWiki has not recorded a supervision or regulatory status for this substance.
Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
No register row and no identity class settled the question.
No source is stored against this line.
What is in the pack
Sold as capsule, given by the oral route.
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 and what that means for what is in the pack.
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 takeNothing found in the sources checked
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.
Nothing found in the sources checked
No harm is recorded against this substance in the sources RNAWiki checked. Finding nothing is not the same as showing there is nothing.
The sources listed were searched and held nothing. That is not the same as nothing existing.
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 unclearRead 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
Oral
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
Not recorded.
Nothing recorded
Where this came from
RNAWiki holds nothing here and says so rather than guessing.
Nothing further is recorded about which forms are sold.
No source is stored against this line.
What is recorded as being sold
3 products list this as an active ingredient in the United States drug directory. 3 of them contain it and nothing else.
FDA National Drug Code directory · 0071-0525 · read 2026-08-29
They are sold as capsule and powder, taken oral.
FDA National Drug Code directory · 0071-0525 · read 2026-08-29
The regulator's established pharmacologic class for it is anti-epileptic agent [epc] and decreased central nervous system disorganized electrical activity [pe].
FDA National Drug Code directory · 0071-0525 · read 2026-08-29
2 published labels name it as an active ingredient. 2 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 5138e347-665b-4dd6-b9f8-12f4a807ed4e · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · 5138e347-665b-4dd6-b9f8-12f4a807ed4e · read 2026-08-29
Methsuximide is oral at HOW SUPPLIED Methsuximide Capsules, USP are supplied as pale yellow colored, size "1" hard gelatin capsules, imprinted 228 on the cap and 300 mg on the body in black ink filled with white to off-white powder with each c…, recorded as fda label in effect 2023-05-03 in the United States.
US prescribing information · 5138e347-665b-4dd6-b9f8-12f4a807ed4e · read 2026-08-30
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 takeRead 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.
RNAWiki could not confidently classify this substance, so no self-experiment plan is offered.
Questions worth asking
- Which of the trials of Mesuximide 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 unclearRead from sources, not yet reviewed
What nobody knows yet
Open questions, each with why it is open and what would close it.
How much did people take in the studies?
The sources RNAWiki checked hold nothing for this field.
Why it matters. A result belongs to an amount. Without the amount the result floats free.
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 Mesuximide 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 peopleRead 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.
Where else this substance is registered
- FDA substance identifier (UNII)
- 0G76K8X6C0
- RxNorm concept
- 197949
Checks this page had to pass
Passed
Identity resolved
no open identity hold
Passed
No unresolved merge across substance families
no quarantine open
Passed
Every public sentence names a source
The opening statement carries the origin: Written into the record, not signed off.
Not passed
Trial roles classified for highlighted evidence
No registered study is classified as testing this substance.
Passed
No internal keys in reader text
enforced by the copy-contract test over the rendered page
Not passed
Safety mode resolved
No register row and no identity class settled the question.
Passed
Canonical metadata present
slug and display name present
What is missing or unclearRead 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
2 approved applications cover products containing this substance. The earliest was NDA010596, approved 19570208 to PARKE DAVIS.
Drugs@FDA application register · NDA010596 · read 2026-08-29
Marketing status on the register: discontinued and prescription.
Drugs@FDA application register · NDA010596 · read 2026-08-29
The earliest marketing start date recorded for a listed product is 19570208.
FDA National Drug Code directory · 0071-0525 · read 2026-08-29
What is missing or unclearRead from sources, not yet reviewed
What to learn next
Ordered by what would most change how you read this page, starting with what is easiest to misunderstand.
- Were people like me actually studied?
- How close is this evidence to something I would notice?
- What does nobody know about this yet?
- What is a biomarker?
This order is fixed in code and does not count clicks or time on the page.
What is not here
10 questions this page could not answer
These sections were prepared and left out because there was nothing to put in them. They are listed rather than hidden, so the gaps in this record are visible.
- What was measured, goal by goal — found nothing in the sources checked.
- What happened in people — found nothing in the sources checked.
- How close this is to real life — found nothing in the sources checked.
- The path through the body — found nothing in the sources checked.
- Felt, measured, or meaningful — found nothing in the sources checked.
- 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.
- Claims that go past the evidence — found nothing in the sources checked.
- What changed on this page — found nothing in the sources checked.
The record as stored
The full record, for auditing
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.
Recorded evidence blocks (6)
On the Mesuximide label: indicated for what?
"Celontin is indicated for the control of absence (petit mal) seizures that are refractory to other drugs.": indications and usage on Mesuximide's label. DailyMed label · 64a6ee88-c6b1-4e13-8208-b6772ef65a74 · 2026-04-07
1 registered trial of Mesuximide — at which phase?
- Registered studies posting no result
- 1 of 1
1 registered study of Mesuximide: 1 na or unstated. CLINICALTRIALS_SNAPSHOT · 2026-09-01
1 with a PubMed record
Show the evidence
- na or unstated1
- completed1
recorded 2026-09-01 · last checked 2026-09-04
Which one trial of Mesuximide posted no result?
- Posted no result
- 1 of 1 completed trials
- Registrations
- NCT03196466
- Completion dates
- oldest 2023-06-15
Show the evidence
- Trial NCT031964662023-06-15
At the median, Mesuximide's trials enrolled 753 people — anything larger?
- Median enrolment
- 753
- Largest enrolment
- 753
- Registered trials counted
- 1
What do 36 spontaneous reports say about Mesuximide — 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.
Mesuximide appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 36 reaction mentions were counted: thrombocytopenia 7; somnolence 6; hospitalisation 5; convulsion 4. FAERS via Open Targets · CHEMBL697 · 2026-06-24
Show the evidence
- thrombocytopenia7
- somnolence6
- hospitalisation5
- convulsion4
- seizure4
- bradyphrenia2
4 more recorded rows
- poor quality product administered2
- resting tremor2
- secretion discharge2
- obesity2
recorded 2026-06-24 · last checked 2026-09-04
Which 10 reactions does Mesuximide's label not list?
bradyphrenia, convulsion and hospitalisation and 7 more reported for Mesuximide, absent from its label. FAERS via Open Targets · CHEMBL697 · 2026-06-24
3 label terms; 10 reported and unlisted; 64a6ee88-c6b1-4e13-8208-b6772ef65a74
Show the evidence
- bradyphreniacount not stated
- convulsioncount not stated
- hospitalisationcount not stated
- obesitycount not stated
- poor quality product administeredcount not stated
- resting tremorcount not stated
4 more recorded rows
- secretion dischargecount not stated
- seizurecount not stated
- somnolencecount not stated
- thrombocytopeniacount not stated
recorded 2026-06-24 · last checked 2026-09-04
Where it is registered
Identifiers, relations and other names
The exact record
- UNII
- 0G76K8X6C0
- ChEMBL id
- CHEMBL697
- PubChem CID
- 6476
- CAS number
- 77-41-8
- RxCUI
- 47858
- InChIKey
- AJXPJJZHWIXJCJ-UHFFFAOYSA-N
- Also called
- METHSUXIMIDE, Mesuximida, 2,5-PYRROLIDINEDIONE,1,3-DIMETHYL-3-PHENYL-, (±)-, MESUXIMIDE [MART.], METHSUXIMIDE [HSDB], METHSUXIMIDE [MI], METHSUXIMIDE [ORANGE BOOK], METHSUXIMIDE [USP MONOGRAPH], METHSUXIMIDE [USP-RS], METHSUXIMIDE [VANDF], Mesuximide [WHO-DD]
- Trade name
- Celontin
- Development code
- NSC-760075
Sources (5)
Sources
- chembl+drugsfda chembl+drugsfda ·
- CLINICALTRIALS_SNAPSHOT K1:0G76K8X6C0 ·
- DailyMed label 64a6ee88-c6b1-4e13-8208-b6772ef65a74 ·
- FAERS via Open Targets CHEMBL697 ·
- Drugs@FDA K1:0G76K8X6C0 ·
ChEMBL 37 — CC BY-SA 3.0 Unported · ChEMBL ATC CC BY-SA · ClinicalTrials.gov — US Government work · Open Targets 26.06 — CC0 · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md · openFDA / DailyMed — US Government work
How these records are assembled · Which registers were checked
Index-quality checks
- identity passed: no open identity hold
- required summary fields resolved: 4 required field(s) not terminal: Why people use it, Best-supported result, Biggest unanswered question, Human evidence
- public claims reviewed: 0 reviewed claim(s); drafts are never rendered
- source coverage passed: 5 source rows
- no critical contamination: no quarantine open
- canonical metadata passed: slug and display name present
- no raw internal fields: enforced by the copy-contract test over the rendered page
This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.