This page shows what was measured, who it was measured in, and what that does not settle.
What Iohexol does in the body
Intrathecal, intra-arterial, intravenous, oral, rectal, intraarticular and body cavity imaging procedures
From the FDA-approved label: The iodine atoms in iohexol provide attenuation of X-rays in direct proportion to the concentration of iohexol. Since concentration changes over time, iohexol provides time-dependent image contrast which may assist in visualizing body structures.
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
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 · 4419T9MX03 · 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 62 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.
Enzyme
An enzyme is a protein that speeds up one chemical change.
A picture of it, and where the picture fails
An enzyme is like a machine on a production line doing one cut.
Where that stops being true. A machine is switched on and off by a person. Enzymes are controlled by the cell.
What people get wrong. Enzymes are thought to be used up. They are not; they work again and again.
A catalytic protein that lowers the activation energy of a specific reaction.
Receptor
A receptor is a part of a cell that a signal fits into.
A picture of it, and where the picture fails
A receptor is like a lock waiting for one key.
Where that stops being true. A lock either opens or does not. A receptor can be half-triggered, or worn out.
What people get wrong. Fitting a receptor is read as causing a benefit. It causes a step, and nothing more.
A protein that binds a specific ligand and converts that binding into a cellular response.
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 39 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
Blood sugar
∅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.
∅Nothing in the sources checkedNo registered study lists a symptom measure for this goal.
△Only a number moved1 registered test measure.
∅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.
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 reviewer1 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
Blood sugar
insulin sensitivity
Pain
pain intensity measure
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.
△ Only a number moved
1 registered test measure.
— Not recorded
Harms were not a registered measure for this goal.
… Waiting for a reviewer
Who was studied is listed further down the page.
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.
Glomerular Filtration Rate (GFR) estimated by iohexol clearance at Week 52 post kidney transplantation
✗ The study did not show it
Who was studied
NCT01363752
How many people
853
Study design
Phase 4
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
Adverse Events (AE)
✗ The study did not show it
Who was studied
NCT03197779
How many people
691
Study design
Phase 1
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
Performance for detection of adenomatous colonic polyps > 6mm
✗ The study did not show it
Who was studied
NCT01200303
How many people
605
Study design
Phase 2/Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
iGFR at the End of the Wash-out Period
✗ The study did not show it
Who was studied
NCT02017171
How many people
530
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
Image Quality of the CT Scans Using Different Contrast Agents
✗ The study did not show it
Who was studied
NCT01534975
How many people
513
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
Incidence of delayed graft function and/or one year acute rejection
✗ The study did not show it
Who was studied
NCT02727296
How many people
488
Study design
Phase 4
Compared against
Not recorded for this study
Kind of result
What a body can do day to day
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated
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. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Injection
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
What we know
RNAWiki holds 6 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.1 registered measure of this kind.
■A number that stands in for healthEvidence recorded. Cholesterol, blood sugar, bone density. A stand-in, not the thing itself.5 registered measures of this kind.
■A step measured inside a personEvidence recorded. Something measured in human tissue or human cells.1 registered measure inside human tissue.
■AnimalsEvidence recorded. Mice, rats, dogs. Useful for ideas, not proof about people.Stored records in Mouse. 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 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.
pain intensity measure
Measured
Things only a test, a scale or a device shows.
maximum observed plasma concentration
effective renal plasma flow
maximum observed plasma concentration of metformin
insulin sensitivity
mitochondrial function
urine sodium excretion
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 (32)
glomerular filtration rate
treatment emergent adverse events
pharmacokinetics renal clearance of metformin
auc from time 0 extrapolated to infinity
terminal elimination half life
terminal elimination rate constant
total body clearance
renal clearance
noncalcified coronary artery plaque volume
incidence of adverse events
incidence of serious adverse events
aes leading to discontinuation
clinically significant changes in vital signs
clinically significant changes in clinical laboratory tests
renal oxygenation
renal perfusion
renal oxygen consumption
arterial pressure
dose limiting toxicities
adequate bowel preparation
These are harms, study-process measures, or names the rules did not recognise. They are shown rather than dropped.
What it would be like to take◇Read from sources, not yet reviewed
How long anything takes
Nine different lengths of time that get confused with each other. None of them is worked out from another.
Before anything is noticed.RNAWiki does not store this separately, and never works it out from another figure on this page.
Before a test result moves.RNAWiki does not store this separately, and never works it out from another figure on this page.
Before performance moves.RNAWiki does not store this separately, and never works it out from another figure on this page.
How long the result was watched.No finished study window is recorded for a study that tested this substance.
How long people took it.How long people actually took it is not stored. The study window is not the same thing.
How long people were followed.Follow-up length is not stored separately. It is never read off the study window, which would be a different thing.
How fast the body clears it. 12.6 hours hours
Read from the label, which states: “12.3 Pharmacokinetics Following the intravenous administration of iohexol (between 500 mg iodine/kg to 1,500 mg iodine/kg) to 16 adult subjects, apparent first-order terminal elimination half-life was 12.6 hours and total body clearance was 131 (98 to 165) mL/min.”
How long effects linger.RNAWiki does not store this separately, and never works it out from another figure on this page.
Beyond the studies. Nothing is recorded about the long term.
The longest finished study sets the edge of what anyone measured.
A study window is not how long people took it, and neither is how long they were followed. Where RNAWiki holds only one of the three, it shows one.
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.
Iohexol is a radiographic contrast agent indicated for intrathecal, intra-arterial, intravenous, oral, rectal, intraarticular and body cavity imaging procedures in adults and pediatric patients.
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 pediatric, the label states: “The safety and effectiveness of iohexol have not been established for intrathecal use in pediatric patients less than 2 weeks of age.”
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-30
On older people, the label states: “In clinical studies of iohexol for CT of the head and body, 52 (17%) of patients were 70 and over.”
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-30
On people who are pregnant, the label states: “Risk Summary Hysterosalpingography is contraindicated in pregnant women due to the potential risk to the fetus from an intrauterine procedure [see Contraindications (4) ].”
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-30
On people who are breastfeeding, the label states: “Risk Summary Published literature reports that breast feeding after intravenous iohexol administration to the mother would result in the infant receiving an oral dose of approximately 0.7% of the maternal intravenous dose; however, lactation studies have not been conducted with oral, intrathecal, or intracavity administration of iohexol.”
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-30
On people with reduced kidney function, the label states: “The clearance of iohexol decreases with increasing degree of renal impairment and results in delayed opacification of the urinary system.”
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · 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 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
Injection
✎ 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: S6.
No source is stored against this line.
What is in the pack
Sold as injectable, solution, for solution, injection, solution, given by the injection, injection, oral, rectal, 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 take∅Nothing 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.
Reports sent to a regulator
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.
Iohexol appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 3517 reaction mentions were counted. One report can name several reactions.
The recorded terms (10)
urticaria — 751 reaction mentions
pruritus — 592 reaction mentions
dyspnoea — 437 reaction mentions
erythema — 435 reaction mentions
sneezing — 316 reaction mentions
vomiting — 249 reaction mentions
hypersensitivity — 201 reaction mentions
chills — 192 reaction mentions
contrast media reaction — 175 reaction mentions
cough — 169 reaction mentions
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
Injection
✎ 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
21 products list this as an active ingredient in the United States drug directory. 21 of them contain it and nothing else.
FDA National Drug Code directory · 80830-2467 · read 2026-08-29
They are sold as injection, solution, powder and solution, taken intra-articular, intrathecal, intravascular and intravenous.
FDA National Drug Code directory · 80830-2467 · read 2026-08-29
The regulator's established pharmacologic class for it is radiographic contrast agent [epc] and x-ray contrast activity [moa].
FDA National Drug Code directory · 80830-2467 · read 2026-08-29
5 published labels name it as an active ingredient. 5 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · read 2026-08-29
Iohexol is intra-articular at 3 DOSAGE FORMS AND STRENGTHS Injection: Clear, colorless to pale yellow solution available in the following presentations: Dosage Form Concentration (mg of iodine/mL) Package Size Package Type Injection 300 50 mL, 75 mL…, recorded as fda label in effect 2026-06-30 in the United States.
US prescribing information · ff9456ef-c45a-450d-9004-a684af2bcc59 · 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 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 Iohexol 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
What nobody knows yet
Open questions, each with why it is open and what would close it.
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 Iohexol 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.
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4419T9MX03
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Recorded evidence blocks (11)
Q2
What did Iohexol's largest trial (3979 people) and its longest (8.3 years) measure?
3979 people in Iohexol's largest registered study, 8.3 years in its longest registered window, measuring Relationship between TFV pharmacology, iGFR,and frailty score in older versus younger adults. ClinicalTrials.gov · 2026-09-01
19 phase1, 17 na or unstated, 13 na, 11 phase4, 6 phase2, 4 phase3, 2 early phase1; NCT02276066; 2023-05-20. Last human test completed 2026, NCT06709521.
Interpretation These counts include studies where Iohexol 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
phase1
19
na or unstated
17
na
13
phase4
11
phase2
6
phase3
4
2 more recorded rows
early phase1
2
Last recorded human testNCT06709521
2026-07-02
recorded 2026-09-01 · last checked 2026-09-04
Q3
From mouse to human: where has Iohexol shown healthspan?
Interpretation Relationship between TFV pharmacology, iGFR,and frailty score in older versus younger adults — the recorded outcome words.
Show the evidence
mouse
mechanism-only
humanNCT02304263
healthspan; Relationship between TFV pharmacology, iGFR,and frailty score in older versus younger adults; 69
recorded 2026-09-01 · last checked 2026-09-04
Q4
9 of Iohexol's trials stopped: safety, futility/efficacy, accrual/recruitment, funding/business, other?
safety (1), futility/efficacy (1), accrual/recruitment (2), funding/business (2) and other (3): Iohexol's stop wording, clustered. ClinicalTrials.gov · 2026-09-01
"Business decision"; 9 of 69 registered studies
Show the evidence
Trial
NCT01188486
terminated; "Business decision"
NCT01839526
terminated; "Enrollment period not extended and screening stopped for slow recruitment and in accordance with provisions of the protocol. Not linked to any safety concern"
NCT02928458
withdrawn; "Inadequate enrollment"
NCT03545087
withdrawn; "Stopped for futility. Phase 3 studies not likely to meet primary endpoints."
NCT03631771
withdrawn; "It was determined that a study is no longer required because the clinical question posed by the study has been answered through published literature"
NCT04199754
terminated; "Slow accrual rate due to national contrast shortage"
3 further recorded trials
NCT04504331
terminated; "Drug manufacturer decision to terminate development."
NCT04627831
withdrawn; "Internal decision"
NCT05580250
withdrawn; "The sponsor made a business decision to withdraw the trial."
recorded 2026-09-01 · last checked 2026-09-04
Q5
Human studies of Iohexol used Iohexol Inj 300 MG/ML — over how long?
5 recorded entries; human; also "Iohexol Inj 300 MG/ML", "Iohexol Inj 300 mg/mL", "Omnipaque 300mg/mL Solution for Injection"
Show the evidence
human
NCT03584217
Iohexol Inj 300 MG/ML
NCT03618420
Iohexol Inj 300 mg/mL
NCT04199754
Omnipaque 300mg/mL Solution for Injection
NCT05065372
Iohexol 300 Mg/mL Injectable Solution
NCT05319990
Iohexol Inj 300 MG/ML Diagnostic aid/agent used to measure glomerular filtration rate (GFR)
recorded 2026-09-01 · last checked 2026-09-04
Q6
Iohexol's half-life is 12.6 hours — which schedules were studied?
12.6 hours, the half-life Iohexol's label states. openfda-label · ff9456ef-c45a-450d-9004-a684af2bcc59 · 2026-08-30
Show the evidence
half life
12.6 hours hours; 12.3 Pharmacokinetics Following the intravenous administration of iohexol (between 500 mg iodine/kg to 1,500 mg iodine/kg) to 16 adult subjects, apparent first-order terminal elimination half-life was 12.6 hours and total body clearance was 131 (98 to 165) mL/min.
metabolism
Distribution In 16 adult subjects (receiving between 500 mg iodine/kg to 1,500 mg iodine/kg intravenous iohexol) the plasma volume of distribution was 165 (108 to 219) mL/kg. In five adult patients receiving 16 mL to 18 mL of iohexol (180 mg iodine/mL) by lumbar intrathecal injection the plasma volume of distribution was 559 (350 to 849) mL/kg. Elimination Metabolism No significant metabolism,…
recorded 2026-08-30 · last checked 2026-09-04
Q7
Which of adequate bowel preparation, aes leading to discontinuation and arterial pressure did Iohexol's trials measure?
adequate bowel preparation, aes leading to discontinuation and arterial pressure lead 39 outcome terms across Iohexol's trials. ClinicalTrials.gov · 2026-09-01
maximum observed plasma concentration, auc from time 0 extrapolated to infinity, terminal elimination half life, terminal elimination rate constant, total body clearance and renal clearance follow.
Show the evidence
glomerular filtration rate
1
treatment emergent adverse events
1
pharmacokinetics renal clearance of metformin
1
maximum observed plasma concentration
1
auc from time 0 extrapolated to infinity
1
terminal elimination half life
1
14 more recorded rows
terminal elimination rate constant
1
total body clearance
1
renal clearance
1
effective renal plasma flow
1
noncalcified coronary artery plaque volume
1
maximum observed plasma concentration of metformin
1
incidence of adverse events
1
incidence of serious adverse events
1
aes leading to discontinuation
1
clinically significant changes in vital signs
1
clinically significant changes in clinical laboratory tests
1
renal oxygenation
1
renal perfusion
1
renal oxygen consumption
1
recorded 2026-09-01 · last checked 2026-09-04
Q8
Which of Iohexol's 13 ongoing trials reports first?
Effective renal plasma flow (ERPF); Accuracy of achieving the targeted carboplatin area under the curve (AUC); latest 2028-06-30
Show the evidence
Trial
NCT03584217
"Renal HEIR Study: Renal Hemodynamics, Energetics and Insulin Resistance in Youth Onset Type 2 Diabetes Study"; n 100; "Effective renal plasma flow (ERPF)"; 2023-10-30
NCT03997370
"Evaluation of Dosing Procedures of Chemotherapy Treatment (Carboplatin) With the Contrast Agent Iohexol"; n 350; "Accuracy of achieving the targeted carboplatin area under the curve (AUC)"; 2028-03-14
NCT04126824
"Effect of Addition of Steroids on Duration of Analgesia"; n 28; "Change in Pain Intensity Measure (mm)"; 2027-08-02
NCT05008276
"Puberty, Diabetes, and the Kidneys, When Eustress Becomes Distress (PANTHER Study)"; n 100; "Effective renal plasma flow (ERPF)"; 2027-12-01
NCT05065372
"MANATEE-T1D: Metformin ANd AutomaTEd Insulin Delivery System Effects on Renal Vascular Resistance, Insulin Sensitivity, and Cardiometabolic Function in Youth With Type 1 Diabetes"; n 60; "Renal vascular resistance"; 2027-07-31
NCT05319990
"Pathogenesis of Kidney Disease in Type 1 Diabetes: a Modern Kidney Biopsy Cohort (The PANDA Study)"; n 100; "Renal Oxygenation"; 2027-12-31
7 further recorded trials
NCT05442463
"Hormone Therapy and Angiotensin-Dependent Arterial and Renal Vasoconstriction in Humans"; n 200; "First association in transgender women and cis women"; 2025-11-30
NCT05694624
"Investigations Into Sepsis-associated Acute Kidney Injury"; n 20; "Hemodynamics"; 2026-12-31
NCT07174440
"Contrast and Anesthetic Level With Lumbar Erector Spinae Plan (ESP) Block"; n 32; "Verbal pain score as measured by the numerical rating scale (NRS)"; 2027-01-25
NCT07339722
"A Study of LY4515100 in Healthy Participants"; n 123; "Number of participants with one or more serious adverse event(s) (SAEs) of LY4515100 in Parts A and B"; 2027-03
NCT07349797
"MediBeacon® Transdermal GFR System for the Evaluation of Kidney Function in Adults With Heart Failure"; n 15; "Correlation of Transdermal Derived Glomerular Filtration Rate (tGFR) to the Plasma-derived Indexed Glomerular Filtration Rate (nGFR)"; 2027-01
NCT07450534
"The Practicality and Utility of Measured vs Estimated GFR in adCKD"; n 150; "Iohexol measured glomerular filtration rate"; 2027-02
NCT07643467
"Fluorescent Probe for Assessment of Renal Elimination"; n 200; "Transdermal Glomerular Filtration Rate (tGFR) Monitoring Accuracy"; 2028-06-30
recorded 2026-09-01 · last checked 2026-09-04
Q9
Which 23 trials of Iohexol posted no result?
Posted no result
23 of 23 completed trials
Registrations
NCT00734825, NCT01214993, NCT01984411, NCT02522338, NCT02342925 and NCT01545531, and 17 more
Completion dates
oldest 2010-09; newest 2024-08-27
Show the evidence
Trial
NCT00734825
2010-09
NCT01214993
2010-11
NCT01984411
2013-08
NCT02522338
2013-12
NCT02342925
2015-05
NCT01545531
2016-01
14 further recorded trials
NCT02050269
2016-06
NCT02304263
2016-09
NCT03095391
2017-09-20
NCT03415997
2018-11-09
NCT02133599
2019-02-27
NCT03826602
2019-03-15
NCT03869983
2019-06-15
NCT04156750
2020-08-03
NCT04008992
2021-01-04
NCT05179564
2021-02-07
NCT04742816
2021-12-31
NCT04407481
2022-10-13
NCT02961478
2022-11-11
NCT04074668
2022-11-15
Q10
At the median, Iohexol's trials enrolled 50 people — anything larger?
Median enrolment
50
Largest enrolment
3979
Registered trials counted
69
Q11
What do 3517 spontaneous reports say about Iohexol — 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.
Iohexol appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 3517 reaction mentions were counted: urticaria 751; pruritus 592; dyspnoea 437; erythema 435. open-targets-adr · CHEMBL1200455 · 2026-06-24
Show the evidence
urticaria
751
pruritus
592
dyspnoea
437
erythema
435
sneezing
316
vomiting
249
4 more recorded rows
hypersensitivity
201
chills
192
contrast media reaction
175
cough
169
recorded 2026-06-24 · last checked 2026-09-04
Q12
What is recorded about Iohexol and AMPK?
"HMGB1 silencing was able to inhibit overactivation of AMPK/Beclin-1 axis during CI-AKI, and iohexol-downregulated protein expressions of GPX4 and SLC7A11 were reversed in kidneys of AMPK knockout mice." — where Iohexol and AMPK appear together. Europe PMC · pathway abstract search · 2025-08-31
"HMGB1 silencing was able to inhibit overactivation of AMPK/Beclin-1 axis during CI-AKI, and iohexol-downregulated protein expressions of GPX4 and SLC7A11 were reversed in kidneys of AMPK knockout mice."
autophagy
PMID 34228649
"In mice with iohexol-induced AKI, ALDH2 knockdown in RTECs using AAV-shRNA impaired autophagy activation and aggravated renal injury."
PMID 34228649
"In human renal proximal tubular epithelial HK-2 cells exposed to iohexol, ALDH2 activation potentiated autophagy and attenuated apoptosis."
AMPK
PMID 31560952
"Furthermore, febuxostat enhanced AMPK phosphorylation and inhibited Nox1, Nox2, and HIF-1α expression in iohexol-exposed HK-2 cells."
PMID 31560952
"AMPK inhibition using small interfering RNA blunted the antioxidative effects of febuxostat in iohexol-treated HK-2 cells."
sirtuin
PMID 29035878
"SIRT1 inhibition using siRNA in tubular cells accentuated the decrease of cell viability by iohexol."
PMID 31402864
"For <i>in vitro</i> experiments, renal tubular epithelial (HK-2) cells subjected to high glucose conditions were treated with resveratrol, Ex527, an SIRT1 inhibitor, or 2-methoxyestradiol (2-MeOE2), HIF-1α inhibitor, before treatment with iohexol."
PMID 29368247
"Human proximal tubular epithelial cells (HK-2) were cultured in DMEM/F12 medium in vitro and then randomly divided into appropriate experimental groups: normal group (N), dimethyl sulfoxide (DMSO), iohexol group (I), iohexol + (1.0, 10.0 μmol/L) astaxanthin group (I + LAST; I + HAST), iohexol + SIRT1 inhibitors (nicotinamide) group (NA) and iohexol + si-RNA FOXO3a group (si-RNA FOXO3a); when…"
autophagyPMID 28944925
"These results provided evidence to suggest that autophagy is activated in response to iohexol‑induced cell injury and apoptosis, and may exert a renoprotective role in HK‑2 cells."
recorded 2025-08-31 · last checked 2026-09-04
Where it is registeredIdentifiers, relations and other names
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 · openFDA / DailyMed — US Government work
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