Ropivacaine
Naropin
Amide local anesthetic, long-acting
S-enantiomer of propivacaine. Less lipid-soluble than bupivacaine → less cardiotoxicity but slightly less potency.
Indications
- •Peripheral nerve blocks
- •Epidural
- •Wound infiltration
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Epidural | 0.2–0.5% bolus; 0.1–0.2% infusion | — |
| Peripheral block | 0.5–0.75% 20–40 mL | — |
| Local infiltration | Max 3 mg/kg plain | — |
Maximum dose
3 mg/kg plain (absolute max 200 mg)
Max-dose calculator
single-injection infiltration / blockPlain
200 mg
Capped at absolute max 200 mg
| Concentration | Max volume (plain) |
|---|---|
| 0.2% (2 mg/mL) | 100 mL |
| 0.5% (5 mg/mL) | 40 mL |
| 0.75% (7.5 mg/mL) | 26.7 mL |
| 1% (10 mg/mL) | 20 mL |
Intrinsic vasoconstriction — epinephrine adds little, so no separate epi max. Education only — confirm against the package insert. Max doses are not additive across agents; account for total LA when mixing.
Pharmacokinetics
Onset 5–15 min. Duration 4–8 h. Hepatic CYP1A2 + CYP3A4.
Side effects
- !LAST (less than bupivacaine but still possible)
- !Motor-sparing at low concentrations (useful for OB labor + ambulatory)
Contraindications
- ×Bier block
Clinical pearls
- ★Better motor/sensory differential than bupivacaine — preferred for labor epidurals at 0.0625–0.1%.
- ★Slightly less potent than bupivacaine — may need 1.2–1.5× dose for equivalent block.
Other drugs in Local Anesthetics
- Lidocaine
Blocks voltage-gated Na⁺ channels in nerves (LA) and cardiac myocytes (antiarrhythmic).
- Bupivacaine
Voltage-gated Na⁺ channel blocker. Higher protein binding and lipid solubility than lidocaine → longer duration but greater cardiotoxicity.
- Tetracaine
Blocks voltage-gated Na⁺ channels. Long-acting ester, metabolized by plasma cholinesterase. High potency + toxicity.
- Chloroprocaine
Na⁺-channel blocker. Extremely rapid plasma-cholinesterase metabolism (half-life seconds) → lowest systemic toxicity of the LAs, ideal for OB epidural top-up.
- Procaine
Na⁺-channel blocker; prototype ester LA. Plasma-cholinesterase metabolized to PABA.
- Prilocaine
Na⁺-channel blocker. Metabolized to o-toluidine → oxidizes hemoglobin → methemoglobinemia at high doses.
- Levobupivacaine
The S(−)-enantiomer of bupivacaine → similar block with LESS cardiotoxicity + CNS toxicity than racemic bupivacaine.
- Articaine
Amide LA that uniquely also has a thiophene ester group → partial plasma-esterase metabolism → shorter systemic half-life. Excellent bone/tissue penetration in dentistry.
Browse all classes: /reference/drugs
Suggested reading
- •Stoelting & Hines, Pharmacology & Physiology in Anesthetic Practice, 6e
- •FDA package insert
- •ASRA LAST checklist, 2020
