This page shows what was measured, who it was measured in, and what that does not settle.
What Vancomycin does in the body
Serious infections caused by bacteria resistant to common antibiotics.
Most antibiotics of this kind jam the tool a bacterium uses to build its wall. Vancomycin does something different: it clamps onto the bricks themselves, so the tool has nothing it can pick up. That is why it still works against bacteria that have swapped their tool for one penicillins cannot grip. The molecule is far too big to be absorbed from the gut, so swallowing it treats only the bowel and injecting it treats everywhere else.
What happened in people
For resistant hospital pneumonia, linezolid produced more cures and less kidney injury, while deaths were unchanged.
✓ Reviewed first-read answer
Where this came from
A person wrote this and a reviewer approved it against this exact record. It carries no effect size.
A reviewer approved this against this record. The reviewed-claim record carrying the exact population and effect size does not exist yet.
No source is stored against this line.
The limit that matters most
The blood-level target used worldwide came from looking back at treatment records, not a direct comparison.
Where it acts
The outer face of the bacterial cytoplasmic membrane, where peptidoglycan precursors are assembled. Taken by mouth it stays in the gut lumen and goes nowhere else.
Kind of result
The kind of result is not recorded
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
Its recorded molecular formula is C66H75Cl2N9O24•HCl, weighing 1485.71 g/mol.
US prescribing information · b9a7c728-750b-467f-bf61-54dd836dba1b · read 2026-08-30
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.
The limit a reviewer approved as the one that matters most here.
The four opening statements run to 104 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.
Comparator
A comparator is whatever the treatment was measured against.
A picture of it, and where the picture fails
It is like the other runner in a race.
Where that stops being true. A race has one winner. A study can show both arms improved.
What people get wrong. Results are read without asking what the other group got. Beating nothing is not beating a treatment.
The control condition against which the experimental intervention is assessed.
Randomisation
Randomisation means chance decides who gets which treatment.
A picture of it, and where the picture fails
It is like a coin toss deciding the groups.
Where that stops being true. A coin toss is fair once. Fairness here comes from doing it for everyone.
What people get wrong. It is thought to make groups identical. It makes them similar on average, including on things nobody measured.
Allocation of participants to arms by a chance process, so that unmeasured factors are balanced in expectation.
Absolute difference
An absolute difference is how many more people in a hundred were affected.
A picture of it, and where the picture fails
It is like counting heads in two rooms of a hundred.
Where that stops being true. Heads are easy to count. Study results carry a margin of error too.
What people get wrong. It is confused with a percentage change, which can look far larger.
The arithmetic difference in event rates between arms.
Confidence interval
A confidence interval is the range the true answer is likely to sit in.
A picture of it, and where the picture fails
It is like a weather forecast giving a range rather than one number.
Where that stops being true. A forecast range covers tomorrow. This one covers what the study could resolve.
What people get wrong. The middle number is read as the answer. A range crossing zero means no change is still possible.
An interval estimate that would contain the true parameter in a stated proportion of repeated studies.
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.
Clinical outcome at end of study in evaluable per-protocol patients with MRSA nosocomial pneumonia
Vancomycin 46.6% (81 of 174) against linezolid 57.6% (95 of 165); 95% CI for the difference 0.5% to 21.6%, P=.042 in favour of linezolid
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. 1,184 patients were treated but only 448 entered the modified intention-to-treat and 348 the per-protocol population, so the primary result rests on under a third of those exposed. Sixty-day mortality was identical between arms, which is the outcome most readers care about and the one the trial did not separate.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed
Interval reported. 95% CI for the difference 0
Written into the record, not signed off as a reviewed claim.
Standard therapy 41.7% (48 of 115) against daptomycin 44.2% (53 of 120); absolute difference 2.4%, 95% CI -10.2 to 15.1, non-inferiority met
Repeated elsewhere
Partially Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. The comparator arm mixed vancomycin with antistaphylococcal penicillins and added initial low-dose gentamicin, so its 26.3% renal dysfunction rate cannot be attributed to vancomycin alone. Success rates in both arms were below 45%, which is the more striking number and is rarely quoted.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed
Interval reported. 95% CI -10
Written into the record, not signed off as a reviewed claim.
Vancomycin 85.8% against fidaxomicin 88.2% by modified intention to treat, non-inferiority met; recurrence 25.3% against 15.4%, 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. The primary endpoint was cure, on which the drugs matched. The recurrence difference, a secondary endpoint, is what changed practice, and it was concentrated in patients with non-NAP1 strains rather than distributed evenly.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
RNAWiki holds 3 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.
What 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
Vancomycin
What a person takes: Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed.
The measurement behind this step
The two routes are effectively two drugs. Intravenous vancomycin does not reach useful concentrations in the colonic lumen and does not treat Clostridioides difficile infection; oral vancomycin achieves high luminal concentrations with essentially no systemic exposure and treats nothing outside the gut. Intravenous administration must be given slowly diluted, over not less than 60 minutes, because rapid infusion causes direct histamine release.
Getting in
Two completely different drugs in one molecule
Injected, it treats infections anywhere in the body. Swallowed, it treats only the bowel, because the molecule is far too big to be absorbed. The same powder is two medicines depending on the route.
╌╌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
At 1,449 daltons vancomycin has negligible oral bioavailability. Oral capsules deliver high luminal colonic concentrations with essentially no systemic exposure, which is why they treat Clostridioides difficile infection and nothing else, and why the intravenous form does not treat it.
Some bacteria have an extra outer skin with small pores. Vancomycin is simply too large to fit through them, so it never reaches its target in those organisms. That is a physical limit, not a resistance mechanism.
╌╌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
Exclusion by the Gram-negative outer membrane is a size limitation, which is why the spectrum is Gram-positive only and why no Gram-negative organism has ever needed to evolve resistance to it.
Penicillins jam the tool that lays the bricks. Vancomycin grips the end of the brick itself, so no tool can pick it up. It does not matter which tool the bacterium has.
╌╌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 rigid cup of the heptapeptide aglycone forms five hydrogen bonds with the D-alanyl-D-alanine terminus of lipid II, the membrane-anchored peptidoglycan precursor. Sequestering the substrate blocks both transglycosylation and transpeptidation. Because MRSA’s resistance mechanism is an altered transpeptidase, and vancomycin does not touch transpeptidases, MRSA is fully susceptible.
With the building material locked up, the wall cannot be extended or repaired, and the growing bacterium fails.
╌╌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
Killing is slow relative to beta-lactams, time-dependent, and requires active growth. The comparatively slow bactericidal action is one proposed explanation for its underperformance against beta-lactams in methicillin-susceptible infection.
A bacterium cannot dodge vancomycin by changing a protein. It has to manufacture a different building block, which takes a whole set of borrowed genes. That is why resistance is common in enterococci and almost unheard of in Staphylococcus aureus.
╌╌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 vanA and vanB operons substitute D-alanyl-D-lactate for D-alanyl-D-alanine, losing one hydrogen bond and roughly a thousandfold of affinity. Acquisition requires horizontal transfer of a multi-gene operon with its regulatory system, not a point mutation.
Vancomycin can damage the kidneys, and rarely hearing, and the risk rises with how much drug the body is exposed to. That is why it is one of the few antibiotics whose blood level is measured routinely.
╌╌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 label states that systemic exposure may result in acute kidney injury and that risk increases as systemic exposure and serum levels increase; interstitial nephritis is also reported. Ototoxicity, transient or permanent, has occurred mostly with excessive exposure, pre-existing hearing loss or concomitant ototoxic agents. Nephrotoxicity was 18.2% against linezolid’s 8.4% in ZEPHyR. Infusion-rate reactions are separate and are direct histamine release rather than allergy.
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.
Hospitalised adults and children with serious Gram-positive infection, especially MRSA bloodstream infection and endocarditis. Taken by mouth, patients with Clostridioides difficile infection.
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: “Vancomycin hydrochloride for oral solution is indicated in pediatric patients less than 18 years of age for the treatment of C. difficile -associated diarrhea and enterocolitis caused by S. aureus (including methicillin-resistant strains) [ see Indications and Usage ( 1 ) and Dosage and Administration ( 2.3 ) ].”
US prescribing information · b9a7c728-750b-467f-bf61-54dd836dba1b · read 2026-08-30
On older people, the label states: “In clinical trials, 54% of vancomycin hydrochloride-treated subjects were > 65 years of age.”
US prescribing information · b9a7c728-750b-467f-bf61-54dd836dba1b · read 2026-08-30
On people who are pregnant, the label states: “Risk Summary There are no available data on vancomycin hydrochloride for oral solution use in pregnant women to inform a drug-associated risk of major birth defects or miscarriage.”
US prescribing information · b9a7c728-750b-467f-bf61-54dd836dba1b · read 2026-08-30
On people who are breastfeeding, the label states: “Risk Summary There are insufficient data to inform the levels of vancomycin in human milk.”
US prescribing information · b9a7c728-750b-467f-bf61-54dd836dba1b · read 2026-08-30
Where the result stopped carrying
It lost the only large head-to-head trial in MRSA nosocomial pneumonia on clinical success, though not on mortality
It relapses roughly ten percentage points more often than fidaxomicin in Clostridioides difficile infection despite matching it on cure
Success in Staphylococcus aureus bacteraemia was under 45% in both arms of the randomised trial — the disease remains poorly treated by any agent
Early preparations were impure enough to be nicknamed Mississippi mud, and much of the drug’s toxicity reputation was formed against material no modern specification would pass
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
Given by a clinician
❝ 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
Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed
✎ 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: S3.
No source is stored against this line.
What is in the pack
The two routes are effectively two drugs.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on how this is sold. The rest of the recorded wording: Intravenous vancomycin does not reach useful concentrations in the colonic lumen and does not treat Clostridioides difficile infection; oral vancomycin achieves high luminal concentrations with essentially no systemic exposure and treats nothing outside the gut. Intravenous administration must be given slowly diluted, over not less than 60 minutes, because rapid infusion causes direct histamine release.
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
Rapid bolus administration may cause exaggerated hypotension including shock and rarely cardiac arrest; the characteristic flushing of the upper body is an infusion-rate reaction rather than an allergy, and mislabelling it as one costs patients an option they may need. Systemic exposure may cause acute kidney injury, with risk rising as exposure rises; interstitial nephritis is also reported. Ototoxicity, transient or permanent, has occurred mostly with excessive exposure, pre-existing hearing loss or concomitant ototoxic drugs. Severe dermatologic reactions including toxic epidermal necrolysis, Stevens-Johnson syndrome, DRESS, acute generalised exanthematous pustulosis and linear IgA bullous dermatosis have been reported. Reversible neutropenia has been reported, usually a week or more into therapy.
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
Intravenous infusion for systemic infection; oral capsules and solution for Clostridioides difficile infection, which are not absorbed
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form used in the studies cited on this page.
No source is stored against this line.
What is sold
A recorded note compares this form with the others that are sold. It is kept below, word for word.
§ A fixed RNAWiki sentence
Where this came from
Wording RNAWiki always uses, not a finding about this substance.
The recorded note, unchanged: Intravenous vancomycin does not reach useful concentrations in the colonic lumen and does not treat Clostridioides difficile infection; oral vancomycin achieves high luminal concentrations with essentially no systemic exposure and treats nothing outside the gut. Intravenous administration must be given slowly diluted, over not less than 60 minutes, because rapid infusion causes direct histamine release.
No source is stored against this line.
What is recorded as being sold
173 products list this as an active ingredient in the United States drug directory. 173 of them contain it and nothing else.
FDA National Drug Code directory · 72162-2305 · read 2026-08-29
They are sold as capsule, injection, powder, for solution, injection, powder, lyophilized, for solution, injection, solution, powder and powder, for solution, taken intravenous, intravitreal and oral.
FDA National Drug Code directory · 72162-2305 · read 2026-08-29
The regulator's established pharmacologic class for it is glycopeptide antibacterial [epc] and glycopeptides [cs].
FDA National Drug Code directory · 72162-2305 · read 2026-08-29
79 published labels name it as an active ingredient. 79 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 86950e7c-0114-47e9-8891-e09e595c48c3 · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · 86950e7c-0114-47e9-8891-e09e595c48c3 · read 2026-08-29
Vancomycin Hydrochloride is powder for injection (vials) at 500 mg vial and 1 gram vial (equivalent to vancomycin), recorded as prescription product; fda label in effect 2026-01-30 in the United States.
US prescribing information · 00946db3-d6c5-4534-a870-1ec6e63eda43 · read 2026-08-27
Recorded price in US: 0.39487–2.90936 USD per one millilitre, across 14 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
Recorded price in US: 1.41225–2.7041 USD per one unit as the pricing file counts it — a tablet, capsule, patch or single item, across 29 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.
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 Vancomycin 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 achieving a specific exposure-to-MIC ratio improves outcomes across all the infections vancomycin treats — derived retrospectively from one respiratory cohort and never randomised
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 exposure-guided monitoring prevents kidney injury, supported by pooled observational data the reviewers themselves graded low certainty
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 26.3% renal dysfunction rate in the bacteraemia trial is attributable to vancomycin, when the arm also contained beta-lactams and gentamicin
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 sixty years of safe use implies the drug is well characterised; most of what is known about how to use it was worked out after approval, without trials
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 Vancomycin 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.
ZEPHyR: 46.6% clinical success against linezolid’s 57.6% in MRSA pneumonia
In plain words
In the only large head-to-head trial of vancomycin against linezolid in hospital-acquired MRSA pneumonia, with vancomycin doses adjusted by blood levels, fewer than half the vancomycin patients were counted as successes. More than twice as many had kidney injury. The same proportion of each group was alive at sixty days.
What was measured
Clinical outcome at end of study in the per-protocol population, and nephrotoxicity incidence
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
ZEPHyR was a prospective, double-blind, controlled, multicentre trial in hospitalised adults with hospital-acquired or healthcare-associated MRSA pneumonia. Of 1,184 patients treated, 448 entered the modified intention-to-treat population and 348 the per-protocol population. Clinical success at end of study in the per-protocol population was 95 of 165 (57.6%) with linezolid against 81 of 174 (46.6%) with vancomycin — 95% confidence interval for the difference 0.5% to 21.6%, P=.042. All-cause 60-day mortality was similar at 15.7% and 17.0%, and overall adverse event rates were similar. Nephrotoxicity was more frequent with vancomycin, 18.2% against 8.4%. Vancomycin dosing was adjusted on trough levels, so this is not a comparison against under-dosed vancomycin.
Written into the record, not signed off as a reviewed claim
The exposure target the world monitors it against is retrospective
In plain words
Vancomycin is one of the very few antibiotics whose blood level is routinely measured, and the number those levels are aimed at was worked out by looking back at what happened to patients who happened to receive different amounts. No trial randomised anyone to different targets and counted the outcomes.
What was measured
That achieving a specific area-under-the-curve to minimum-inhibitory-concentration ratio improves clinical outcome across the range of infections vancomycin treats — extrapolated from one retrospective respiratory-infection cohort and never tested by randomising patients to different targets
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The pharmacodynamic index used for vancomycin is the ratio of the 24-hour area under the concentration-time curve to the minimum inhibitory concentration, and the threshold value in general use derives from Moise-Broder and colleagues’ retrospective pharmacokinetic and pharmacodynamic analysis of patients with Staphylococcus aureus lower respiratory tract infections. That is an observational exposure-response analysis in a single infection type, generalised since to bloodstream infection, endocarditis, bone infection and skin infection, none of which it studied. The 2020 revised consensus guideline from the Infectious Diseases Society of America, the Society of Infectious Diseases Pharmacists, the American Society of Health-System Pharmacists and the Pediatric Infectious Diseases Society is built on this index, and it states its own evidence base rather than concealing it. No randomised trial has compared clinical outcomes between exposure targets.
Written into the record, not signed off as a reviewed claim
Monitoring moved from a single trough value to total exposure in 2020
In plain words
For years vancomycin was monitored by one blood level taken just before the next dose, because it was easy. In 2020 the guideline moved to estimating total drug exposure instead. The evidence for the change is a set of observational comparisons rated low-certainty, not a trial.
What was measured
That trough-guided monitoring was causing avoidable kidney injury and exposure-guided monitoring prevents it — supported by pooled observational comparison at low certainty, and adopted worldwide on that basis
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The 2020 revised consensus guideline replaced trough-only monitoring with area-under-the-curve-guided monitoring for serious MRSA infection. A systematic review and meta-analysis of 10 studies in 4,231 patients found area-under-the-curve-guided strategies associated with significantly less vancomycin-induced acute kidney injury than trough-guided strategies: odds ratio 0.625 (95% CI 0.469 to 0.834, p=0.001, I2 25.5%), and 0.475 (95% CI 0.261 to 0.863, p=0.015) in the three studies reporting adjusted odds ratios. Stratified by definition, the association reached significance using the guideline definition of acute kidney injury (OR 0.552, 95% CI 0.341 to 0.894, p=0.016) and not using the alternatives. The authors graded the overall certainty as low and named confounding bias and inconsistent injury definitions as the limitations. The change was made on this evidence, which is better than what preceded it and is not a randomised comparison.
Written into the record, not signed off as a reviewed claim
Renal dysfunction in 26.3% of the standard-therapy arm against 11.0% on daptomycin
In plain words
In the randomised trial of bloodstream infection and heart-valve infection caused by Staphylococcus aureus, roughly a quarter of the patients on the older regimen — which was vancomycin or an antistaphylococcal penicillin, plus gentamicin — developed clinically significant kidney problems. On the newer drug it was about one in nine.
What was measured
Clinically significant renal dysfunction and 42-day treatment success in randomised Staphylococcus aureus bacteraemia
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The trial randomised 124 patients with Staphylococcus aureus bacteraemia with or without endocarditis to daptomycin and 122 to initial low-dose gentamicin plus either an antistaphylococcal penicillin or vancomycin. Success at 42 days after end of therapy in the modified intention-to-treat analysis was 53 of 120 (44.2%) against 48 of 115 (41.7%) — absolute difference 2.4%, 95% CI -10.2 to 15.1, meeting the pre-specified non-inferiority criteria. Clinically significant renal dysfunction occurred in 11.0% on daptomycin against 26.3% on standard therapy, P=.004. The comparator arm mixes vancomycin with beta-lactams and adds gentamicin, so the renal figure is not attributable to vancomycin alone — but gentamicin was low-dose and brief, and the direction is consistent with ZEPHyR’s 18.2% against 8.4%.
Written into the record, not signed off as a reviewed claim
For bowel infection it cures as well as fidaxomicin and relapses far more often
In plain words
Swallowed vancomycin treats a completely different disease from injected vancomycin, because none of it is absorbed. In the head-to-head trial for that disease it cured just as many people as the newer drug and then had them come back with it roughly ten percentage points more often.
What was measured
Clinical cure and 4-week recurrence of Clostridioides difficile infection, oral vancomycin against fidaxomicin
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
A phase 3 trial randomised 629 adults with acute Clostridioides difficile infection and a positive stool toxin test to oral fidaxomicin or oral vancomycin for 10 days, with 548 evaluable per protocol. Clinical cure with fidaxomicin was non-inferior in both the modified intention-to-treat analysis (88.2% against 85.8%) and the per-protocol analysis (92.1% against 89.8%). Recurrence within four weeks was significantly lower with fidaxomicin in both: 15.4% against 25.3% (P=0.005) and 13.3% against 24.0% (P=0.004). The recurrence advantage was seen in patients with non-NAP1 strains rather than uniformly. Adverse event profiles were similar. The likely explanation is spectrum: vancomycin suppresses the surrounding colonic flora that would otherwise resist recolonisation, and fidaxomicin disturbs it less.
Written into the record, not signed off as a reviewed claim
Resistance requires rebuilding the target, which is why it took so long
In plain words
Vancomycin does not attack an enzyme, it grabs the building material. A bacterium cannot escape by tweaking a protein — it has to manufacture a different brick. That is a much bigger genetic undertaking, and it is why sixty years of heavy use has produced widespread resistance in enterococci and almost none in Staphylococcus aureus.
What was measured
Fold change in binding affinity between the D-Ala-D-Ala and D-Ala-D-Lac ligands
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The vanA and vanB operons encode a set of enzymes that replace the D-alanyl-D-alanine terminus of the peptidoglycan precursor with D-alanyl-D-lactate. That single substitution removes one of the five hydrogen bonds vancomycin makes with its ligand and reduces binding affinity by roughly three orders of magnitude. Acquiring it requires horizontal transfer of a multi-gene operon plus the regulatory machinery to switch it on, not a point mutation — which is the structural reason vancomycin-resistant enterococci are common while fully vancomycin-resistant Staphylococcus aureus remains vanishingly rare despite decades of exposure.
Source
Vancomycin Hydrochloride for Injection United States prescribing information, Microbiology; mechanism as characterised in the glycopeptide resistance literature
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
How many documents were read
80 documents were read for this substance.
RNAWiki source record
14 of them state the same volumeOfDistribution, and they agree.
RNAWiki source record
Where else this substance is registered
FDA substance identifier (UNII)
71WO621TJD
CAS registry number
1404-90-6
PubChem compound
14969
RxNorm concept
11124
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Suppression classes recorded: S3.
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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.
Withdrawn in United States, 2024, for "Superpotent Drug: Due to overfilling of drug powder" (openFDA drug enforcement Class I recall)
Withdrawn in United States, 2017, for "Presence of Particulate Matter: glass particulate found in vial" (openFDA drug enforcement Class I recall)
Withdrawn in United States, 2022, for "Presence of Particulate Matter: Glass particulate matter detected in injectable." (openFDA drug enforcement Class I recall)
What the approval register records
68 approved applications cover products containing this substance. The earliest was ANDA060180, approved 19641106 to STERISCIENCE.
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.
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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 glycopeptide that binds the bacterial wall’s building block rather than the enzyme that assembles it, so resistance requires rebuilding the block itself — in the head-to-head MRSA pneumonia trial it achieved clinical success in 46.6% of per-protocol patients against linezolid’s 57.6% (P=.042) with nephrotoxicity in 18.2% against 8.4%, and the exposure target the entire world monitors it against comes from a retrospective pharmacokinetic analysis rather than a randomised trial.
Recorded evidence blocks (10)
Q2
On the Vancomycin label: indicated for what?
"TYZAVAN is a glycopeptide antibacterial indicated for the treatment of the following infections in adult and pediatric patients (1 month and older) for whom appropriate dosing with this formulation can be achieved: Septicemia ( 1.1 ) Infective Endocarditis ( 1.2 ) Skin and Skin Structure Infections ( 1.3 ) Bone…": indications and usage on Vancomycin's label. DailyMed label · 72e9c5e2-07cc-4a8b-ba64-b2e7619ea560 · 2026-08-19
Q3
299 registered trials of Vancomycin — at which phases?
Registered studies posting no result
197 of 299
299 registered studies of Vancomycin: 82 phase4, 75 phase2, 65 phase3, 43 na, 31 phase1, 17 na or unstated, 4 early phase1. CLINICALTRIALS_SNAPSHOT · 2026-09-01
"See Detailed Description"; 56 of 299 registered studies
Show the evidence
Trial
NCT00108433
terminated; "See Detailed Description"
NCT00384527
terminated; "Study was terminated early due to slow recruitment."
NCT00435305
terminated; "difficulties by enrolling patients fundings consumed, no staff could be recruited and payed to continue enrolling patients,"
NCT00543608
terminated; "Trial terminated due to financial resource limitations"
NCT00695903
terminated; "terminated due to lack of enrollment"
NCT00925093
withdrawn; "Primary investigator left institution"
14 further recorded trials
NCT01104662
terminated; "Cubist has reached an agreement with the FDA that enrollment in the DAP-RENSE-08-05 study can stop."
NCT01133600
terminated; "Lack of patient enrollment"
NCT01157533
terminated; "Low Accrual."
NCT01175707
terminated; "Business decision"
NCT01196169
terminated; "The study is closed to accrual. Enrollment of new patients stopped at the request of CUBIST Pharmaceuticals due to slow rate of enrollment."
NCT01199783
terminated; "Patient number to be enrolled not reachable in prospected time frame, decision to stop the study prematurely was made."
terminated; "Technical issues with catheter placement; researcher left institution"
NCT01509339
withdrawn; "Lab unable to measure vancomycin levels in Sputum"
NCT01734694
terminated; "Independent biostatistician recommended early termination of the trial due to low probability of success."
NCT01756924
terminated; "This study has been terminated; alternative study designs are being considered. Fusidic acid remains available under an Expanded Access Protocol."
NCT01775397
terminated; "Study terminated due to difficulty in enrollment"
recorded 2026-09-01 · last checked 2026-09-04
Q5
Human studies of Vancomycin used 250 mg Vancomycin * — over how long?
studies of Vancomycin used the recorded amount. ClinicalTrials.gov · 2026-09-01
5 recorded entries; human; by mouth; also "250 mg Vancomycin *", "Vancomycin 125mg by mouth every 6 hours for 10 days", "Vancomycin 250Mg Capsule"
Show the evidence
human
NCT01798537
250 mg Vancomycin *
NCT01818141
by mouth; Vancomycin 125mg by mouth every 6 hours for 10 days
NCT03403972
Vancomycin 250Mg Capsule
NCT05363462
Vancomycin 1000 MG
NCT06126731
Vancomycin 125mg
recorded 2026-09-01 · last checked 2026-09-04
Q6
Vancomycin's half-life is 4 to 6 hours — which schedules were studied?
4 to 6 hours; The mean elimination half-life of vancomycin from plasma is 4 to 6 hours in subjects with normal renal function.
metabolismpharmacokinetics
Metabolism There is no apparent metabolism of the vancomycin.
recorded 2026-08-19 · last checked 2026-09-04
Q7
Which running trial of Vancomycin could settle lifespan?
NCT05137119 measures All-cause mortality at 90 days after platform entry, reading out 2028-12-01.
1 open trial; n 8000; "Staphylococcus Aureus Network Adaptive Platform Trial"
Show the evidence
TrialNCT05137119
"Staphylococcus Aureus Network Adaptive Platform Trial"; n 8000; "All-cause mortality at 90 days after platform entry"; 2028-12-01
Q8
Which 62 trials of Vancomycin posted no result?
Posted no result
62 of 62 completed trials
Registrations
NCT00035425, NCT00572559, NCT00037050, NCT00228982, NCT00251017 and NCT00295178, and 56 more
Completion dates
oldest 2002-11; newest 2024-03-01
Show the evidence
Trial
NCT00035425
2002-11
NCT00572559
2005-01
NCT00037050
2005-07
NCT00228982
2005-12
NCT00251017
2006-06
NCT00295178
2006-08-09
14 further recorded trials
NCT00612469
2006-10
NCT00304811
2007-01
NCT00281281
2007-04
NCT00442832
2007-05
NCT00324922
2007-05-01
NCT00454272
2007-08
NCT00426933
2007-09
NCT00175370
2007-12
NCT00355602
2008-12
NCT00462878
2009-04
NCT01867138
2011-01
NCT01363271
2012-05
NCT01174212
2012-07
NCT01222702
2012-11-12
Q9
At the median, Vancomycin's trials enrolled 80 people — anything larger?
Median enrolment
80
Largest enrolment
38000
Registered trials counted
298
Q10
What do 8376 spontaneous reports say about Vancomycin — 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.
Vancomycin appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 8376 reaction mentions were counted: acute kidney injury 1553; drug hypersensitivity 1223; drug reaction with eosinophilia and systemic symptoms 1089; pyrexia 1081. FAERS via Open Targets · CHEMBL1200628 · 2026-06-24
Show the evidence
acute kidney injury
1553
drug hypersensitivity
1223
drug reaction with eosinophilia and systemic symptoms
1089
pyrexia
1081
rash
852
pruritus
653
4 more recorded rows
renal failure acute
538
thrombocytopenia
486
blood creatinine increased
466
renal tubular necrosis
435
recorded 2026-06-24 · last checked 2026-09-04
Q11
Which 10 reactions does Vancomycin's label not list?
2 label terms; 10 reported and unlisted; 72e9c5e2-07cc-4a8b-ba64-b2e7619ea560
Show the evidence
acute kidney injury
count not stated
blood creatinine increased
count not stated
drug hypersensitivity
count not stated
drug reaction with eosinophilia and systemic symptoms
count not stated
pruritus
count not stated
pyrexia
count not stated
4 more recorded rows
rash
count not stated
renal failure acute
count not stated
renal tubular necrosis
count not stated
thrombocytopenia
count not stated
recorded 2026-06-24 · last checked 2026-09-04
Where it is registered
Where it’s registered
Withdrawn in United States, 2024, for "Superpotent Drug: Due to overfilling of drug powder" (openFDA drug enforcement Class I recall)
Withdrawn in United States, 2017, for "Presence of Particulate Matter: glass particulate found in vial" (openFDA drug enforcement Class I recall)
Withdrawn in United States, 2022, for "Presence of Particulate Matter: Glass particulate matter detected in injectable." (openFDA drug enforcement Class I recall)
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 · openFDA enforcement — US Government work
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