This page shows what was measured, who it was measured in, and what that does not settle.
What Mupirocin does in the body
No isoleucine gets loaded, protein production halts, and the bacterium stops.
To build a protein, a cell must first attach each amino acid to its matching carrier molecule, and a dedicated enzyme does that for each amino acid. Mupirocin is shaped almost exactly like isoleucine already joined to the cell’s energy currency — the fleeting intermediate that enzyme normally makes. It slots into the enzyme and will not leave. The equivalent human enzyme is built differently enough that the drug ignores it. The molecule is also destroyed within minutes in blood, which is why it exists only as an ointment.
Why people take it. Impetigo and small infected skin wounds, and clearing staph from the nose before surgery
What happened in people
Staphylococcus aureus surgical-site infection 2.3% on intranasal mupirocin against 2.4% on placebo in 3,864 randomised patients — primary endpoint not met
✎ 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.
2.3% on mupirocin against 2.4% on placebo — no significant reduction. In the 891-patient carrier subgroup, nosocomial S. aureus infection 4.0% against 7.7%, odds ratio 0.49 (95% CI 0.25 to 0.92), P=0.02
Repeated elsewhere
Partially Replicated
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 result this trial is cited for is a subgroup, and on a different endpoint from the primary one — all nosocomial S. aureus infections rather than surgical-site infections. Both facts are stated plainly in the paper and routinely lost in citation.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ointment 2%, cream 2%, and a separate nasal ointment
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
3.4% (17/504) against 7.7% (32/413), relative risk 0.42 (95% CI 0.23 to 0.75); deep surgical-site infection relative risk 0.21 (95% CI 0.07 to 0.62); time to onset shorter on placebo, P=0.005
Repeated elsewhere
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. All S. aureus strains identified in the trial were susceptible to both methicillin and mupirocin, which is stated in the results and constrains generalisability. There was no significant difference in all-cause in-hospital mortality. The intervention was two drugs, so the mupirocin contribution alone is not separable.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ointment 2%, cream 2%, and a separate nasal ointment
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
Cure rate, topical antibiotic against placebo and against comparators
✓ The study showed what it set out to show
Who was studied
Cochrane interventions for impetigo (CD003261)
How many people
5578
Study design
Systematic review and meta-analysis of 68 randomised controlled trials
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Topical antibiotic against placebo RR 2.24 (95% CI 1.61 to 3.13); mupirocin against fusidic acid RR 1.03 (95% CI 0.95 to 1.11); mupirocin against oral erythromycin RR 1.07 (95% CI 1.01 to 1.13)
Repeated elsewhere
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. Most studies did not provide enough information to assess risk of bias and only 15 reported blinding. Three review authors were authors of an included trial and two disclosed manufacturer funding for a retapamulin study added in the update.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ointment 2%, cream 2%, and a separate nasal ointment
Interval reported. 95% CI 1
Written into the record, not signed off as a reviewed claim.
Systematic review and meta-analysis of prevalence studies, 2000 to 2018
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
MuRSA 7.6% (95% CI 6.2 to 9.0); MuRMRSA 13.8% (95% CI 12.0 to 15.6); HLMuRSA 8.5% (95% CI 6.3 to 10.7); HLMuRMRSA 8.1% (95% CI 6.8 to 9.4)
Repeated elsewhere
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. Sample size counts included studies rather than isolates. Prevalence surveys are geographically uneven and reflect where surveillance is done rather than where resistance is.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ointment 2%, cream 2%, and a separate nasal ointment
Interval reported. 95% CI 6
Written into the record, not signed off as a reviewed claim.
RNAWiki holds 4 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 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
Mupirocin
What a person takes: Topical ointment 2%, cream 2%, and a separate nasal ointment.
The measurement behind this step
Topical only, and necessarily so: the ester bond in the molecule is hydrolysed to inactive monic acid within minutes in plasma, which rules out any systemic formulation. The original ointment used a polyethylene glycol base that is unsuitable for extensive denuded skin because the glycol is absorbed; the cream and paraffin-based ointment exist for that reason. The nasal preparation is formulated to persist in the anterior nares against mucociliary clearance.
Getting in
Applied to skin or to the front of the nose
The ointment goes where the bacteria are — on the crusted skin of impetigo, or just inside the nostril where staph lives quietly in about a quarter of people.
╌╌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
The anterior nares are the principal reservoir of Staphylococcus aureus and the source of most endogenous surgical site infections: 23.1% of completers in the Perl trial carried it. Nasal decolonisation depends on maintaining local concentration against mucociliary clearance rather than on systemic exposure, of which there is none.
To build a protein, a bacterium first joins each amino acid to the cell’s energy currency for a fraction of a second. Mupirocin is shaped like that fleeting pairing, made permanent.
╌╌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
Mupirocin is a structural mimic of isoleucyl-adenylate, the transient enzyme-bound intermediate formed from isoleucine and ATP. It competes with both substrates for the active site of bacterial isoleucyl-tRNA synthetase and binds reversibly with high affinity.
The enzyme is jammed and isoleucine is never loaded
With the enzyme occupied, no isoleucine gets attached to its carrier. Every protein that needs isoleucine — which is nearly all of them — stalls.
╌╌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
Inhibition of isoleucyl-tRNA synthetase depletes charged tRNA-Ile, halting translation and triggering the stringent response. No other clinically used antibiotic class inhibits an aminoacyl-tRNA synthetase this way, so cross-resistance with other classes does not arise.
Human cells are untouched, and so is the bloodstream
The human version of the same enzyme is built differently and ignores the drug. And blood destroys the molecule within minutes, so it cannot be given any other way than on a surface.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
The eukaryotic isoleucyl-tRNA synthetase active site differs and is not inhibited. The ester linking monic acid to 9-hydroxynonanoic acid is rapidly hydrolysed in plasma to inactive monic acid, which is why no systemic formulation exists or can exist.
On skin, cure rates roughly double compared with placebo. In the nose, treating screened carriers cut hospital staph infections from about eight per cent to about three.
╌╌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
Impetigo: topical antibiotic against placebo RR 2.24 (95% CI 1.61 to 3.13). Decolonisation of screened carriers: S. aureus infection 3.4% against 7.7%, RR 0.42 (95% CI 0.23 to 0.75), with deep surgical-site infection RR 0.21 (95% CI 0.07 to 0.62).
The decolonisation trial counted infections, not deaths, and found no difference in deaths. And every organism in it was susceptible to the drug, which is no longer true everywhere.
╌╌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
No significant difference in all-cause in-hospital mortality in the Bode trial. All strains identified in that trial were susceptible to methicillin and mupirocin. Pooled resistance now stands at 7.6% for S. aureus overall, 13.8% among MRSA and 8.5% for high-level resistance, which is plasmid-borne and transmissible.
No suggested links are held for this record, so nothing is hidden from this path.
What we know
The record describes 6 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 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.
People with impetigo or a small infected wound, and surgical patients found to carry Staphylococcus aureus in the nose.
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 mupirocin cream have been established in the age-groups 3 months to 16 years.”
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-30
On older people, the label states: “In 2 adequate and well‑controlled trials, 30 subjects older than 65 years were treated with mupirocin cream.”
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-30
On people who are pregnant, the label states: “Risk Summary There are insufficient human data to establish whether there is a drug-associated risk with mupirocin cream in pregnant women.”
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-30
On people who are breastfeeding, the label states: “Risk Summary It is not known whether mupirocin is present in human milk, has effects on the breastfed child, or has effects on milk production.”
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-30
Where the result stopped carrying
The largest randomised prophylaxis trial missed its primary endpoint outright and is cited for a subgroup on a different endpoint
All-cause in-hospital mortality did not differ in the trial that established screen-and-decolonise
Against oral erythromycin the advantage was RR 1.07 with a lower bound of 1.01 — statistically present, clinically slight
High-level, plasmid-borne mupirocin resistance is rising globally in the organism the drug exists to eradicate
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 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 (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 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
Topical ointment 2%, cream 2%, and a separate nasal ointment
✎ 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
Topical only, and necessarily so: the ester bond in the molecule is hydrolysed to inactive monic acid within minutes in plasma, which rules out any systemic formulation. The original ointment used a polyethylene glycol base that is unsuitable for extensive denuded skin because the glycol is absorbed; the cream and paraffin-based ointment exist for that reason. The nasal preparation is formulated to persist in the anterior nares against mucociliary clearance.
✎ 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◇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
Well tolerated. In the impetigo review, reported side effects were low and mostly mild, and were more common with oral than with topical treatment, the difference driven mainly by gastrointestinal effects. Local burning, stinging and itching are the usual complaints. Systemic exposure is negligible because the molecule is destroyed in plasma. The cream’s indication is bounded by lesion size — up to 10 cm in length or 100 cm2 in area — because that is the population it was tested in, and the polyethylene glycol vehicle of the original ointment is a specific caution on large open areas.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
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
Topical ointment 2%, cream 2%, and a separate nasal ointment
✎ 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
The original ointment used a polyethylene glycol base that is unsuitable for extensive denuded skin because the glycol is absorbed; the cream and paraffin-based ointment exist for that reason. The nasal preparation is formulated to persist in the anterior nares against mucociliary clearance.
✎ 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 which forms are sold and how they compare.
No source is stored against this line.
What is recorded as being sold
56 products list this as an active ingredient in the United States drug directory. 56 of them contain it and nothing else.
FDA National Drug Code directory · 85766-207 · read 2026-08-29
They are sold as cream, ointment and powder, taken topical.
FDA National Drug Code directory · 85766-207 · read 2026-08-29
The regulator's established pharmacologic class for it is rna synthetase inhibitor antibacterial [epc] and rna synthetase inhibitors [moa].
FDA National Drug Code directory · 85766-207 · read 2026-08-29
43 published labels name it as an active ingredient. 43 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-29
MUPIROCIN is topical at 3 DOSAGE FORMS AND STRENGTHS Mupirocin cream USP, 2% is a white to off white cream that contains 20 mg (2% w/w) of mupirocin per gram in an oil-and water-based emulsion, supplied in 15-gram and 30-gram tubes., recorded as fda label in effect 2025-03-18 in the United States.
US prescribing information · 0580458d-7178-4031-8ac7-0cda281ade8b · read 2026-08-30
Recorded price in US: 0.14537–0.90747 USD per one gram, across 20 priced products whose strengths and pack forms differ, as of 2026-08-26, paid by retail pharmacies buying the product, as surveyed by the Centers for Medicare & Medicaid Services. It is not a list price, an insurance price, or what anyone pays at a counter..
Recorded source · 2026-08-26 · read 2026-08-28
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.
RNAWiki could not confidently classify this substance, so no self-experiment plan is offered.
Questions worth asking
Which of the trials of Mupirocin 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 2002 trial demonstrated mupirocin prevents surgical-site infection — its primary endpoint was 2.3% against 2.4%
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 decolonisation result obtained where every strain was susceptible transfers to settings where 13.8% of MRSA is resistant
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 decolonisation reduces mortality, when the trial that established it found no difference in in-hospital deaths
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 the benefit shown by mupirocin plus chlorhexidine belongs to mupirocin, when the two were given together and never separately
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.
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 Mupirocin 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.
The 4,030-patient prophylaxis trial missed its primary endpoint
In plain words
The largest randomised trial of nasal mupirocin before surgery found no difference in surgical wound infections: 2.3 per cent on the drug and 2.4 per cent on placebo. The result the trial is remembered for came from a subgroup analysis.
What was measured
Staphylococcus aureus surgical-site infection, 2.3% against 2.4% in 3,864 patients
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
Perl and colleagues randomised 4,030 patients undergoing general, gynaecologic, neurologic or cardiothoracic surgery to intranasal mupirocin or placebo, with 3,864 in the intention-to-treat analysis. Overall, 2.3% of mupirocin recipients and 2.4% of placebo recipients had Staphylococcus aureus infections at surgical sites — the primary endpoint, not met. Among the 891 patients (23.1% of completers) who carried S. aureus in the anterior nares, 4.0% of mupirocin recipients had nosocomial S. aureus infections against 7.7% on placebo (odds ratio 0.49, 95% CI 0.25 to 0.92, P=0.02). The authors state the conclusion precisely: prophylactic intranasal mupirocin did not significantly reduce surgical-site S. aureus infections overall, but did significantly decrease all nosocomial S. aureus infections among carriers. Note that the subgroup result is also on a different endpoint from the primary one.
Written into the record, not signed off as a reviewed claim
Screening first, then treating only carriers, cut infections by more than half
In plain words
A later trial screened everyone on admission with a rapid genetic test and treated only the carriers. Infections fell from 7.7 per cent to 3.4 per cent, and deep wound infections by nearly eighty per cent. Deaths did not change.
What was measured
Hospital-associated Staphylococcus aureus infection in screened carriers, 3.4% against 7.7%
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Bode and colleagues screened 6,771 patients on admission with a real-time PCR assay; 1,270 swabs from 1,251 patients were positive and 917 entered the intention-to-treat analysis, of whom 88.1% underwent surgery. Treatment was mupirocin nasal ointment plus chlorhexidine soap against placebo. Staphylococcus aureus infection occurred in 3.4% (17 of 504) against 7.7% (32 of 413), relative risk 0.42 (95% CI 0.23 to 0.75). The effect was most pronounced for deep surgical-site infections, relative risk 0.21 (95% CI 0.07 to 0.62). Time to onset of nosocomial infection was shorter in the placebo group (P=0.005). There was no significant difference in all-cause in-hospital mortality. Registered as ISRCTN56186788.
Written into the record, not signed off as a reviewed claim
Every organism in that trial was susceptible, and the paper says so
In plain words
The trial that made decolonisation standard practice was run where no strain in it was resistant to either methicillin or mupirocin. That is stated in the results, and it is exactly the condition that no longer holds in much of the world.
What was measured
That a decolonisation result obtained where every strain was mupirocin-susceptible transfers to settings where a substantial minority are not — the condition is stated in the trial’s own results and is not met globally
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The Bode trial reports: "All the S. aureus strains identified on PCR assay were susceptible to methicillin and mupirocin." The trial was conducted in Dutch hospitals between October 2005 and June 2007, in a country with an aggressive search-and-destroy MRSA policy and correspondingly low prevalence. Transporting a relative risk of 0.42 into a setting where a pooled 13.8% of MRSA isolates are mupirocin-resistant and 8.1% carry high-level resistance requires assuming the intervention works the same way when a meaningful fraction of target organisms cannot be eradicated by it. The trial also found no difference in all-cause in-hospital mortality, so the demonstrated benefit is on infection counts rather than on survival.
Written into the record, not signed off as a reviewed claim
Impetigo: better than placebo, level with fusidic acid, barely ahead of a tablet
In plain words
Across 68 trials in more than five thousand people, topical antibiotics roughly doubled the cure rate against placebo. Mupirocin and fusidic acid could not be told apart. Against an oral antibiotic mupirocin came out ahead by seven per cent relative, an interval that only just clears no difference.
What was measured
Pooled cure rate ratios for topical antibiotic against placebo, against fusidic acid and against oral erythromycin
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The 2012 Cochrane review of interventions for impetigo included 68 trials with 5,578 participants reporting on 50 different treatments. Topical antibiotic treatment beat placebo (pooled RR 2.24, 95% CI 1.61 to 3.13; 6 studies, 575 participants). Mupirocin and fusidic acid were indistinguishable (RR 1.03, 95% CI 0.95 to 1.11; 4 studies, 440 participants). Topical mupirocin was slightly superior to oral erythromycin (pooled RR 1.07, 95% CI 1.01 to 1.13; 10 studies, 581 participants), with no significant differences against other oral antibiotics. Topical antibiotics beat disinfecting treatments (RR 1.15, 95% CI 1.01 to 1.32; 2 studies, 292 participants). Reported side effects were low and mostly mild, and more common with oral than topical treatment, the difference driven mainly by gastrointestinal effects. Most studies did not provide enough information to assess risk of bias, and only 15 reported blinding of participants and outcome assessors.
Written into the record, not signed off as a reviewed claim
Resistance is now measurable and rising, including the high-level kind
In plain words
The drug that hospitals rely on to clear staph from noses is losing ground. Pooling studies from 2000 to 2018, about one staph isolate in thirteen was mupirocin-resistant, rising to about one MRSA isolate in seven.
What was measured
That mupirocin remains uniformly effective for decolonisation — pooled resistance is 7.6% overall and 13.8% among MRSA, with high-level plasmid-borne resistance rising over time
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
A meta-analysis of studies published between 2000 and 2018 found pooled prevalences of mupirocin-resistant Staphylococcus aureus at 7.6% (95% CI 6.2 to 9.0) from 30 studies, mupirocin-resistant MRSA at 13.8% (95% CI 12.0 to 15.6) from 63 studies, high-level mupirocin-resistant S. aureus at 8.5% (95% CI 6.3 to 10.7) from 27 studies and high-level mupirocin-resistant MRSA at 8.1% (95% CI 6.8 to 9.4) from 60 studies. The authors report a global increase in high-level resistance over time, with a significant increase specifically in mupirocin-resistant MRSA. High-level resistance is conferred by mupA, a plasmid-borne second copy of the isoleucyl-tRNA synthetase gene (ileS-2) whose product the drug does not bind; low-level resistance arises from point mutations in the native enzyme. Because they are transmissible and non-transmissible respectively, the distinction matters more than the numbers do.
Written into the record, not signed off as a reviewed claim
Reducing infection counts is not the same as saving lives
In plain words
The trial that showed decolonisation works measured infections. It also measured deaths in hospital, and found no difference between the groups.
What was measured
That nasal decolonisation reduces deaths — the trial that established it measured in-hospital mortality and found no significant difference, and was not powered to
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The Bode trial states that there was no significant difference in all-cause in-hospital mortality between the mupirocin-chlorhexidine group and placebo. The Perl trial did not demonstrate an effect on its primary infection endpoint at all. Neither trial was powered for mortality, and a reduction in deep surgical-site infection from a relative risk of 0.21 is a clinically meaningful outcome in its own right. But the step from fewer infections to fewer deaths is an inference here, not a measurement, and decolonisation programmes are frequently justified in the stronger terms.
Written into the record, not signed off as a reviewed claim
A target no other antibiotic uses, and a molecule blood destroys in minutes
In plain words
Mupirocin blocks an enzyme no other antibiotic class touches, so bacteria resistant to everything else are usually still sensitive to it. It is also broken down almost instantly in blood, which is why it can only ever be a cream.
What was measured
Mechanism of action and route restriction as stated in the approved label and reflected in the absence of any systemic formulation
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Mupirocin is a structural analogue of isoleucyl-adenylate and reversibly inhibits bacterial isoleucyl-tRNA synthetase, competing with both isoleucine and ATP. No other clinically used antibiotic class targets an aminoacyl-tRNA synthetase in this way, so cross-resistance with other classes does not occur. The eukaryotic enzyme is not inhibited. The ester bond joining the monic acid moiety to 9-hydroxynonanoic acid is hydrolysed rapidly in plasma to inactive monic acid, which precludes systemic administration entirely — an unusual case where a molecule’s metabolic fragility is the reason its indication is confined to a surface.
Source
Mupirocin Cream 2% United States prescribing information, Indications and Usage and Microbiology sections, as held on the record
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
Where else this substance is registered
FDA substance identifier (UNII)
D0GX863OA5
CAS registry number
12650-69-0
PubChem compound
446596
ChEMBL
CHEMBL719
ChEBI
34858
WHO international nonproprietary name list entry
5276
RxNorm concept
42372
EMA substance identifier
100000092377
DrugBank
DB00410
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 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
16 approved applications cover products containing this substance. The earliest was NDA050591, approved 19871231 to GLAXOSMITHKLINE.
This order is fixed in code and does not count clicks or time on the page.
What is not here
7 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.
How close this is to real life — 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.
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.
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 Pseudomonas natural product that mimics isoleucine locked onto ATP and jams the bacterial enzyme that loads isoleucine onto tRNA — better than placebo for impetigo (RR 2.24, 95% CI 1.61 to 3.13) and indistinguishable from fusidic acid, but its 4,030-patient surgical prophylaxis trial missed its primary endpoint (2.3% against 2.4%) and is remembered for a carrier subgroup, with pooled high-level resistance now at 8.5%.
Recorded evidence blocks (9)
Q1
On the Mupirocin label: indicated for what?
"Mupirocin Ointment USP, 2% is indicated for the topical treatment of impetigo due to susceptible isolates of Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes) . Mupirocin Ointment USP, 2% is an RNA synthetase inhibitor antibacterial indicated for the topical treatment of impetigo due to…": indications and usage on Mupirocin's label. DailyMed label · 831060e6-17ef-b0a0-e053-2991aa0aeb4f · 2026-08-20
Q2
47 registered trials of Mupirocin — at which phases?
Registered studies posting no result
28 of 47
47 registered studies of Mupirocin: 17 na, 12 phase4, 7 phase2, 6 phase3, 3 early phase1, 3 phase1, 1 na or unstated. CLINICALTRIALS_SNAPSHOT · 2026-09-01
229 with a PubMed record
Show the evidence
na
17
phase4
12
phase2
7
phase3
6
early phase1
3
phase1
3
7 more recorded rows
na or unstated
1
completed
34
unknown
6
terminated
4
active not recruiting
1
not yet recruiting
1
withdrawn
1
recorded 2026-09-01 · last checked 2026-09-04
Q3
5 of Mupirocin's trials stopped: futility/efficacy, accrual/recruitment?
"Interim review showed a statistically significant treatment effect and the DMC recommended that the study be stopped with ongoing follow-up of enrolled subjects"; 5 of 47 registered studies
Show the evidence
Trial
NCT01349192
terminated; "Interim review showed a statistically significant treatment effect and the DMC recommended that the study be stopped with ongoing follow-up of enrolled subjects"
NCT01408056
withdrawn; "Difficulty with recruitment"
NCT02099240
terminated; "Not enough patient enrollment and lack of staffing"
NCT02127658
terminated; "Unable to recruit all planned participants prior to end of funding"
NCT03173053
terminated; "Results interim-analysis"
recorded 2026-09-01 · last checked 2026-09-04
Q4
Human studies of Mupirocin used Mupirocin 2% in Polyethylene Glycol (PEG) Ointment — over how long?
Human studies of Mupirocin used "Mupirocin 2% in Polyethylene Glycol (PEG) Ointment". ClinicalTrials.gov · 2026-09-01
9 recorded entries; human; also "2% Mupirocin Ointment", "Mupirocin 2% Ointment", "2% mupirocin ointment"
Show the evidence
human
NCT00108160
Mupirocin 2% in Polyethylene Glycol (PEG) Ointment
NCT00731783
2% Mupirocin Ointment
NCT01408056
Mupirocin 2% Ointment
NCT01814371
2% mupirocin ointment
NCT01876550
Mupirocin Calcium Cream, 2%
NCT02029872
Mupirocin calcium 2 % ointment
3 more recorded rows
humanNCT02963129
Mupirocina 2% ointment
humanNCT06368856
Mupirocin (50 mg)
humanNCT06368856
Mupirocin (500 mg)
recorded 2026-09-01 · last checked 2026-09-04
Q5
Mupirocin's half-life is 20 to 40 minutes — which schedules were studied?
20 to 40 minutes, the half-life Mupirocin's label states: "Elimination In a trial conducted in 7 healthy adult male subjects, the elimination half-life after intravenous administration of mupirocin was 20 to 40 minutes for mupirocin and 30 to 80 minutes for monic acid." DailyMed label · 831060e6-17ef-b0a0-e053-2991aa0aeb4f · 2026-08-20
Show the evidence
half lifepharmacokinetics
20 to 40 minutes; Elimination In a trial conducted in 7 healthy adult male subjects, the elimination half-life after intravenous administration of mupirocin was 20 to 40 minutes for mupirocin and 30 to 80 minutes for monic acid.
metabolismpharmacokinetics
Metabolism: Following intravenous or oral administration, mupirocin is rapidly metabolized.
recorded 2026-08-20 · last checked 2026-09-04
Q6
Which 13 trials of Mupirocin posted no result?
Posted no result
13 of 13 completed trials
Registrations
NCT00289588, NCT00406913, NCT00400595, NCT01949935, NCT01820455 and NCT01302210, and 7 more
Completion dates
oldest 2005-12; newest 2023-07-15
Show the evidence
Trial
NCT00289588
2005-12
NCT00406913
2006-11
NCT00400595
2010-06
NCT01949935
2013-05
NCT01820455
2014-03
NCT01302210
2014-11
7 further recorded trials
NCT01269541
2015-05-01
NCT04287777
2016-11
NCT02619773
2018-12
NCT01876550
2019-05-06
NCT04047914
2021-07-12
NCT05839158
2022-12-31
NCT06046937
2023-07-15
Q7
At the median, Mupirocin's trials enrolled 80 people — anything larger?
Median enrolment
80
Largest enrolment
23005
Registered trials counted
47
Q8
What do 310 spontaneous reports say about Mupirocin — 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.
Mupirocin appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 310 reaction mentions were counted: macular degeneration 110; drug hypersensitivity 33; pruritus 26; rash 26. FAERS via Open Targets · CHEMBL3989715 · 2026-06-24
Show the evidence
macular degeneration
110
drug hypersensitivity
33
pruritus
26
rash
26
erythema
25
pain
24
4 more recorded rows
toxic epidermal necrolysis
18
staphylococcal infection
17
therapeutic product effect incomplete
16
cheilitis
15
recorded 2026-06-24 · last checked 2026-09-04
Q9
Which 10 reactions does Mupirocin's label not list?
ChEMBL 37 — CC BY-SA 3.0 Unported · 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
✗ 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: 6 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.