This page shows what was measured, who it was measured in, and what that does not settle.
What ROPIVACAINE, (R)- does in the body
Ropivacaine blocks the same sodium gates in nerves that bupivacaine blocks, from the same place inside the channel.
Two things were changed on purpose. Only one of the two mirror-image forms is present, and it is the form that troubles the heart less. And the side chain is one carbon shorter, which makes the molecule less greasy, so less of it partitions into heart muscle and it washes out faster. The block is a little weaker as a result, which is the price of the design.
Why people take it. Numbing an area for surgery or childbirth, chosen when the drug will be given in large volumes and an accident would matter most
What happened in people
No QRS widening at doses where bupivacaine widens it, and depression of systolic but not diastolic left ventricular function
✎ 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.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
That the milligram-for-milligram toxicity advantage is the advantage available clinically — the potency ratio of 0.6 says a substantial part of it is spent buying equal analgesia
Where it acts
Inner pore of the sodium channel, in peripheral nerve axons and cardiac ventricular myocytes
Kind of result
What a body can do day to day
Supervision
RNAWiki has not recorded a supervision or regulatory status for this substance.
What the registries record it as
16 registered substances share the start of this name, which is why a search for it can return more than one thing.
FDA substance registry · A5H73K9U3W · read 2026-08-29
Where each sentence above came from
A person wrote this explanation into the record, with the studies named in the path below.
The recorded use, written for a reader without medical training. Not signed off.
A limit recorded against this substance. Not signed off as a reviewed claim.
The four opening statements run to 128 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.
Incidence of delirium in the first seven postoperative days, assessed twice daily by the Confusion Assessment Method for the Intensive Care Unit
✓ The study showed what it set out to show
Who was studied
Li randomised trial of combined epidural-general anaesthesia versus general anaesthesia in older patients (NCT01661907)
How many people
1802
Study design
Randomised open-label controlled trial
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Delirium 1.8% (15/857) versus 5.0% (43/863); relative risk 0.351, 95% CI 0.197 to 0.627, P<0.001, number needed to treat 31
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. Reported, and important: intraoperative systolic pressure below 80 mmHg in 49% versus 33% (relative risk 1.47, 95% CI 1.31 to 1.65, P<0.001) and vasopressor use in 58% versus 45%. The benefit and the harm are in the same paper and the same patients.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Maximum tolerated dose and unbound plasma concentration for central nervous system symptoms, with echocardiographic and electrophysiological change
✓ The study showed what it set out to show
Who was studied
Knudsen volunteer crossover of intravenous ropivacaine, bupivacaine and placebo
How many people
12
Study design
Randomised double-blind three-way crossover in volunteers
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Maximum tolerated unbound plasma concentration twice as high for ropivacaine (P<0.001); QRS widened by bupivacaine versus placebo (P<0.001) and versus ropivacaine (P<0.01)
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 dose difference itself did not reach significance: 95% confidence limits on the mean difference in maximum tolerated dose were -30 to 7 mg. The unbound concentration difference did.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Maximum tolerated intravenous dose to first definite central nervous system symptoms, with conduction and contractility measures
✓ The study showed what it set out to show
Who was studied
Scott volunteer comparison of acute toxicity of ropivacaine and bupivacaine
How many people
12
Study design
Randomised double-blind crossover in volunteers
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Ropivacaine at least 25% less toxic by tolerated dose; conduction and contractility depression appeared at lower dose and lower plasma concentration with bupivacaine
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. Twelve healthy men, infusion capped at 150 mg, endpoint defined as definite but not severe symptoms. The study is deliberately incapable of observing the cardiac events its result is used to reason about.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Median effective local analgesic concentration in 20 mL for first-stage labour epidural analgesia
✓ The study showed what it set out to show
Who was studied
Polley minimum local analgesic concentration study of epidural ropivacaine versus bupivacaine in labour
How many people
73
Study design
Randomised double-blind up-down sequential allocation study
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Ropivacaine 0.111% (95% CI 0.100 to 0.122) versus bupivacaine 0.067% (95% CI 0.052 to 0.082); potency ratio 0.6 (95% CI 0.49 to 0.74)
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. No difference in motor effects was observed at equipotent concentrations, which contradicts the differential-block marketing claim rather than supporting it.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
Interval reported. 95% CI 0
Written into the record, not signed off as a reviewed claim.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
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
ROPIVACAINE, (R)-
What a person takes: Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags.
The measurement behind this step
Every presentation is preservative-free because the principal routes are epidural and major nerve block, where preservatives are unacceptable. Infusion bags exist because continuous epidural infusion over days is the use case ropivacaine was best suited to, and drawing repeated syringes from ampoules for a multi-day infusion is an error source. Unlike lidocaine and bupivacaine, ropivacaine is not routinely co-formulated with epinephrine, partly because it has intrinsic vasoconstrictor activity at clinical concentrations.
Getting in
Injected into the epidural space or around a major nerve
This drug is chosen where the volume is large — an epidural, a whole limb's nerve supply — because that is where an accident would matter most.
╌╌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
Lower lipid solubility than bupivacaine means less sequestration in local fat and a slightly shorter block, and it means less partitioning into myocardium if the drug reaches the circulation. Ropivacaine also produces vasoconstriction at low concentrations in some vascular beds, which slows its own systemic absorption and is one of the few pharmacological differences that works in its favour without a potency caveat.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Only the electrically neutral form gets through the fatty sheath. Inside the nerve it picks up a proton, and the charged form does the blocking.
──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 pKa near 8.1 is essentially identical to bupivacaine's, so the neutral fraction available at physiological pH is the same and onset time is similar. The difference between the two molecules is not in getting in; it is in how much is available in plasma to reach other tissues, where ropivacaine's higher protein binding and lower partition coefficient both reduce the free fraction.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Only one mirror image is present, and it is the gentler one
Bupivacaine is a half-and-half mixture of two mirror-image molecules and one of them accounts for most of the heart trouble. Ropivacaine ships only the other kind.
╌╌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 sodium channel is itself chiral, so the two enantiomers bind the cardiac channel with different affinity and different off-rates while blocking neuronal conduction comparably. Ropivacaine is manufactured and released as the S-enantiomer with a chiral specification, and enantiomeric purity is a release test rather than a nice-to-have.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
One fewer carbon means less of it reaches the heart
The side chain is three carbons instead of four. That small change makes the molecule less greasy, so less of it dissolves into heart muscle and more of it stays bound to proteins in the blood.
──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
Reduced lipid solubility lowers myocardial partitioning and speeds unbinding from the cardiac sodium channel relative to bupivacaine. The measured consequence in volunteers is a maximum tolerated unbound plasma concentration twice as high, with no QRS widening at doses where bupivacaine widens it. The same reduction in lipid solubility is why the drug is less potent, and the two effects cannot be separated because they have the same cause.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Conduction fails in the target nerve for four to eight hours
The nerve goes quiet in the usual order — pain first, then temperature, then touch, then position sense, then muscle power — and comes back in reverse.
╌╌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
Block is state-dependent and accumulates in fibres that are firing, so small unmyelinated C and small myelinated A-delta fibres are affected at lower concentrations than large A-beta and A-alpha fibres. At equal analgesic effect, Polley found no measurable difference in motor block between ropivacaine and bupivacaine; differential block is a concentration phenomenon common to the class rather than a property unique to this molecule.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
The liver breaks it down and it leaves. Because less of it hides in fat and muscle, the concentration in the blood falls more predictably during a long infusion.
╌╌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
Elimination is hepatic, principally by CYP1A2 to 3-hydroxyropivacaine with a smaller CYP3A4 route to the N-dealkylated metabolite, which matters because CYP1A2 inhibition by fluvoxamine substantially reduces clearance. Systemic clearance and terminal half-life are more favourable than bupivacaine's for continuous infusion, which is part of why the drug is preferred where an epidural will run for days rather than hours.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
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 having epidural analgesia in labour, caesarean sections under epidural, major peripheral nerve blocks for limb surgery, and continuous infusions for postoperative pain.
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 efficacy of ropivacaine hydrochloride injection in pediatric patients have not been established.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
On older people, the label states: “Of the 2,978 subjects that were administered ropivacaine hydrochloride injection in 71 controlled and uncontrolled clinical studies, 803 patients (27%) were 65 years of age or older which includes 127 patients (4%) 75 years of age and over. ropivacaine hydrochloride injection was found to be safe and effective in the patients in these studies.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
On people who are pregnant, the label states: “Risk Summary There are no available human data on use of ropivacaine hydrochloride Injection in pregnant women to evaluate a drug associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
On people who are breastfeeding, the label states: “Risk Summary One publication reported that ropivacaine is present in human milk at low levels following administration of ropivacaine in women undergoing cesarean section.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
On people with reduced liver function, the label states: “Because amide-type local anesthetics such as ropivacaine are metabolized by the liver, these drugs, especially repeat doses, should be used cautiously in patients with hepatic disease.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
On people with reduced kidney function, the label states: “This drug and its metabolites are known to be excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function.”
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
Where the result stopped carrying
The differential motor-sparing claim, when tested at equipotent rather than equal concentrations
The implication that the molecule removes rather than widens the risk of local anaesthetic cardiac arrest, contradicted by published resuscitated cases
Levobupivacaine, the rival enantiomer product that would have made the potency argument moot, was withdrawn from the United States market for commercial rather than scientific reasons
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
Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
✎ 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
Every presentation is preservative-free because the principal routes are epidural and major nerve block, where preservatives are unacceptable.
✎ 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: Infusion bags exist because continuous epidural infusion over days is the use case ropivacaine was best suited to, and drawing repeated syringes from ampoules for a multi-day infusion is an error source. Unlike lidocaine and bupivacaine, ropivacaine is not routinely co-formulated with epinephrine, partly because it has intrinsic vasoconstrictor activity at clinical concentrations.
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
The same class risks apply and the argument for the drug is that they apply at higher plasma concentrations. Inadvertent intravascular or intrathecal injection can cause seizures, cardiovascular collapse and total spinal anaesthesia. Cardiac arrest after ropivacaine nerve block has been reported and successfully resuscitated. The class methaemoglobinaemia warning applies. Continuous epidural technique carries its own hazards independent of the drug — the trial that showed a delirium benefit also showed 50% more intraoperative hypotension and more vasopressor use. Nothing on this page is dosing or technique guidance.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Acute toxicity of ropivacaine compared with that of bupivacaine. Anesth Analg 1989;69:563-569 (26… · a recorded source, not a stored snapshot
Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.
Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
What is missing or unclear◇Read from sources, not yet reviewed
Does the exact form matter?
Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.
The form that was studied
Preservative-free sterile solution for epidural, caudal, major peripheral nerve block and infiltration use, in single-dose ampoules, single-dose vials and ready-to-use infusion bags
✎ 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: Infusion bags exist because continuous epidural infusion over days is the use case ropivacaine was best suited to, and drawing repeated syringes from ampoules for a multi-day infusion is an error source. Unlike lidocaine and bupivacaine, ropivacaine is not routinely co-formulated with epinephrine, partly because it has intrinsic vasoconstrictor activity at clinical concentrations.
No source is stored against this line.
What is recorded as being sold
95 products list this as an active ingredient in the United States drug directory. 95 of them contain it and nothing else.
FDA National Drug Code directory · 83854-013 · read 2026-08-29
They are sold as injection, injection, solution and powder, taken epidural, infiltration and perineural.
FDA National Drug Code directory · 83854-013 · read 2026-08-29
The regulator's established pharmacologic class for it is amide local anesthetic [epc], amides [cs] and local anesthesia [pe].
FDA National Drug Code directory · 83854-013 · read 2026-08-29
28 published labels name it as an active ingredient. 28 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-29
Ropivacaine hydrochloride is epidural at 3 DOSAGE FORMS AND STRENGTHS Ropivacaine Hydrochloride Injection USP is a clear, colorless, preservative-free solution available as: Ropivacaine Hydrochloride Injection Single-Dose, Ready-to-Use, Polypropylene Flexible…, recorded as fda label in effect 2022-08-22 in the United States.
US prescribing information · 643c1729-096e-459c-80c1-78b78e698da6 · read 2026-08-30
Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.
What it would be like to take◇Read from sources, not yet reviewed
What you could measure
This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.
RNAWiki could not confidently classify this substance, so no self-experiment plan is offered.
Questions worth asking
Which of the trials of ROPIVACAINE, (R)- 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 milligram-for-milligram toxicity advantage is the advantage available clinically — the potency ratio of 0.6 says a substantial part of it is spent buying equal analgesia
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 ropivacaine spares motor function beyond what its lower potency explains — no difference in motor effects at equipotent concentrations
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 wider margin in healthy volunteers translates into fewer cardiac arrests in practice; the event is far too rare for any trial to have measured it, and cardiac arrest with ropivacaine is on record
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 delirium benefit of a combined epidural technique is a property of ropivacaine rather than of epidural analgesia, of lower opioid exposure, or of the blunted stress response
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 ROPIVACAINE, (R)- 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.
Volunteers tolerate twice the free plasma concentration before symptoms
In plain words
Twelve healthy men were infused with each drug on separate days and told to stop the infusion when they first felt definite symptoms. They could take about twice as much unbound ropivacaine in the blood as unbound bupivacaine, and only bupivacaine distorted their ECG.
What was measured
Maximum tolerated unbound arterial plasma concentration, QRS width and echocardiographic ventricular function during controlled intravenous infusion
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Knudsen and colleagues ran a randomised double-blind crossover of ropivacaine, bupivacaine and placebo infused at 10 mg per minute in 12 volunteers previously familiarised with lignocaine's central effects. The maximum tolerated dose was higher on ropivacaine in nine of 12 subjects, with 95% confidence limits on the mean difference of -30 to 7 mg — a difference in dose that did not itself reach significance. The maximum tolerated unbound arterial plasma concentration, which is the pharmacologically meaningful quantity, was twice as high for ropivacaine (P<0.001), with thresholds near 0.6 and 0.3 mg/L free drug respectively. Muscular twitching was more frequent after bupivacaine (P<0.05) and symptoms resolved faster after ropivacaine (P<0.05). Bupivacaine widened QRS against placebo (P<0.001) and against ropivacaine (P<0.01), and depressed both systolic and diastolic left ventricular function; ropivacaine depressed systolic function only.
Written into the record, not signed off as a reviewed claim
The original 1989 tolerance study: at least 25% less toxic by tolerated dose
In plain words
The first human comparison, eight years earlier, used the same design and found volunteers could take at least a quarter more ropivacaine before symptoms, with conduction and contractility effects appearing later and at lower plasma levels for bupivacaine.
What was measured
Maximum tolerated intravenous dose to first definite central nervous system symptoms, with electrocardiographic and echocardiographic change
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Scott and colleagues infused ropivacaine and bupivacaine at 10 mg per minute to a maximum of 150 mg in 12 healthy men, randomised, double-blind, at least seven days apart, with a preliminary lidocaine injection to familiarise subjects with the symptoms. Ropivacaine caused fewer central nervous system symptoms and was at least 25% less toxic in terms of the dose tolerated. Both drugs raised heart rate and arterial pressure and reduced stroke volume and ejection fraction with no change in cardiac output, but depression of conductivity and contractility appeared at lower doses and lower plasma concentrations with bupivacaine. This study is where the ropivacaine safety claim originates, and it is an equal-milligram comparison, which is the point audited below.
Source
Scott DB, Lee A, Fagan D, Bowler GM, Bloomfield P, Lundh R. Anesth Analg 1989;69:563-569 (PMID 2679230)
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
A measured potency ratio of 0.6 eats into the safety margin as usually quoted
In plain words
The safety studies gave both drugs by the milligram. But it takes about 1.7 times as much ropivacaine to produce the same pain relief, so comparing equal milligrams compares unequal blocks and flatters the newer drug.
What was measured
That the milligram-for-milligram toxicity difference measured in volunteers is the safety advantage available in clinical use, when the two drugs differ in analgesic potency by a measured factor of 0.6
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Polley and colleagues determined minimum local analgesic concentration by up-down sequential allocation in 73 labouring women at 7 cm dilation or less, using 20 mL epidural test solutions and a visual analogue score of 10 mm or less within 30 minutes as the definition of effect. Ropivacaine's minimum local analgesic concentration was 0.111% weight/volume (95% CI 0.100 to 0.122) against bupivacaine's 0.067% (95% CI 0.052 to 0.082), a potency ratio of 0.6 (95% CI 0.49 to 0.74). Against levobupivacaine by the same method the ratio was 0.83. The correct comparison for a safety claim is a therapeutic index — toxic concentration divided by effective concentration — and the equal-milligram volunteer studies do not supply one. This audit does not say the advantage is imaginary: Knudsen measured a genuine twofold difference in tolerated free concentration. It says the advantage is smaller than the raw dose comparison implies, and that the difference between those two statements is the single most common overreach in this drug's literature.
Written into the record, not signed off as a reviewed claim
The motor-sparing claim did not survive an equipotent comparison
In plain words
Ropivacaine is widely described as blocking pain while leaving muscle power alone. In the study that compared the two drugs at the concentrations that give equal pain relief, there was no difference in motor effects.
What was measured
That ropivacaine has an intrinsic motor-sparing property beyond what its lower potency explains
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
The differential-block claim originates in comparisons at equal concentrations, where ropivacaine, being less potent, produces less of every effect including motor block. Polley's up-down study reported explicitly that no difference in motor effects was observed between the groups when each drug was given at its own minimum local analgesic concentration. The mechanistic story usually attached to the claim — that lower lipid solubility spares large myelinated motor fibres preferentially — is a plausible account of a difference that the equipotent comparison did not find. Differential block between sensory and motor fibres is real and concentration-dependent for every drug in this class; that it is greater for ropivacaine than for bupivacaine at equal effect is the part that failed.
Written into the record, not signed off as a reviewed claim
Safer is not safe: cardiac arrest after a ropivacaine nerve block is on record
In plain words
The drug was designed to make cardiac arrest from local anaesthetic less likely. It has still happened, been published, and been resuscitated from.
What was measured
Not recorded
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
Chazalon and colleagues reported cardiac arrest following a peripheral nerve block with ropivacaine, with successful resuscitation, in Anesthesiology in 2003. A single case report is not an incidence and this page does not present it as one. It is included because the ropivacaine literature is dominated by margin-of-safety measurements in healthy volunteers stopped well short of a cardiac endpoint, and a reader is entitled to know that the endpoint those measurements are used to reason about has occurred in practice. The design goal was to widen a margin, not to remove a risk, and the drug did what it was designed to do rather than what it is sometimes described as doing.
Written into the record, not signed off as a reviewed claim
Epidural ropivacaine cut delirium by two thirds in 1,720 older patients — and caused 50% more hypotension
In plain words
Adding an epidural of ropivacaine to a general anaesthetic in older people having major surgery reduced confusion afterwards from five percent to under two. The same trial found half again as many episodes of dangerously low blood pressure during the operation.
What was measured
Incidence of delirium in the first seven postoperative days, and incidence of intraoperative systolic pressure below 80 mmHg
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Li and colleagues randomised 1,802 patients aged 60 to 90 having major non-cardiac thoracic or abdominal surgery expected to last two hours or more, 1:1, to combined epidural-general anaesthesia with 0.375% to 0.5% epidural ropivacaine and postoperative patient-controlled epidural analgesia, or to general anaesthesia with intravenous morphine analgesia. Of these, 1,720 completed and were analysed by intention to treat. Delirium, assessed twice daily for seven days with the Confusion Assessment Method for the Intensive Care Unit, occurred in 15 of 857 (1.8%) in the epidural group against 43 of 863 (5.0%) in the general anaesthesia group — relative risk 0.351, 95% CI 0.197 to 0.627, P<0.001, number needed to treat 31. In the same patients, intraoperative systolic pressure below 80 mmHg occurred in 421 (49%) versus 288 (33%) — relative risk 1.47, 95% CI 1.31 to 1.65, P<0.001 — and more epidural patients received vasopressors, 495 (58%) versus 387 (45%), relative risk 1.29, 95% CI 1.17 to 1.41, P<0.001. This is a rare thing on this file: a genuine patient-relevant benefit for a local anaesthetic, reported alongside its cost in the same population.
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.
The safer mirror-image of bupivacaine with one carbon removed: volunteers tolerate roughly twice the unbound plasma concentration before symptoms appear and it does not widen the QRS complex where bupivacaine does, but it is also measurably weaker — a minimum local analgesic concentration of 0.111% against bupivacaine's 0.067%, a potency ratio of 0.6 — so a milligram-for-milligram safety comparison overstates the advantage.
Recorded evidence blocks (8)
Q1
On the ROPIVACAINE, (R)- label: indicated for what?
"NAROPIN is indicated for the production of local or regional anesthesia for surgery and for acute pain management. Surgical Anesthesia : epidural block for surgery including cesarean section; major nerve block; local infiltration Acute Pain Management : epidural continuous infusion or intermittent bolus, e.g.,…": indications and usage on ROPIVACAINE, (R)-'s label. DailyMed label · cb6583ff-cde4-4280-aa5b-0bea2b844792 · 2026-07-17
Q2
624 registered trials of ROPIVACAINE, (R)- — at which phases?
Registered studies posting no result
489 of 624
624 registered studies of ROPIVACAINE, (R)-: 230 phase4, 216 na, 87 phase3, 61 phase2, 20 phase1, 19 na or unstated, 14 early phase1. CLINICALTRIALS_SNAPSHOT · 2026-09-01
14 ± 7 minutes; The half-lives of the 2 phases, (mean ± SD) are 14 ± 7 minutes and 4.2 ± 0.9 h, respectively.
metabolismpharmacokinetics
Metabolism Ropivacaine is extensively metabolized in the liver, predominantly by aromatic hydroxylation mediated by cytochrome P4501A to 3-hydroxy ropivacaine.
recorded 2026-07-17 · last checked 2026-09-04
Q6
Which 240 trials of ROPIVACAINE, (R)- posted no result?
Posted no result
240 of 240 completed trials
Registrations
NCT00626977, NCT00150865, NCT00552864, NCT00358280, NCT01054547 and NCT01307969, and 234 more
Completion dates
oldest 2001-12; newest 2024-08-30
Show the evidence
Trial
NCT00626977
2001-12
NCT00150865
2002-03
NCT00552864
2005-06
NCT00358280
2006-09
NCT01054547
2007-04
NCT01307969
2007-06
14 further recorded trials
NCT00433316
2007-10
NCT00910013
2008-03
NCT00567450
2008-09
NCT00603083
2008-10
NCT00573963
2008-11
NCT00529425
2008-12
NCT00620490
2009-03
NCT01247857
2009-03
NCT01248819
2009-05
NCT00724035
2009-07
NCT01512914
2009-09
NCT00769054
2009-10
NCT00702416
2009-11
NCT00295945
2009-12
Q7
At the median, ROPIVACAINE, (R)-'s trials enrolled 60 people — anything larger?
Median enrolment
60
Largest enrolment
22435
Registered trials counted
624
Q8
ROPIVACAINE, (R)- and CYP1A2 and CYP3A4: shared by which compounds?
In vivo, the plasma clearance of ropivacaine was reduced by 70% during coadministration of fluvoxamine (25 mg bid for 2 days), a selective and potent CYP1A2 inhibitor.
drug_interactions
Caution should be exercised when CYP1A2 inhibitors are coadministered.
drug_interactions
Possible interactions with drugs known to be metabolized by CYP1A2 via competitive inhibition such as theophylline and imipramine may also occur.
drug_interactions
Coadministration of a selective and potent inhibitor of CYP3A4, ketoconazole (100 mg bid for 2 days with ropivacaine infusion administered 1 hour after ketoconazole) caused a 15% reduction in in vivo plasma clearance of ropivacaine.
ROPIVACAINE HYDROCHLORIDE MONOHYDRATE IMPURITY G [EP IMPURITY], ROPIVACAINE RELATED COMPOUND B FREE BASE ANHYDROUS, ROPIVACAINE RELATED COMPOUND B [USP IMPURITY]
ClinicalTrials.gov — US Government work · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md · openFDA / DailyMed — US Government work · openFDA enforcement — 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.