Comparative Pharmacology
Head-to-head clinical analysis: EXPAREL versus LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EXPAREL versus LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE.
EXPAREL vs LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Liposomal bupivacaine is a local anesthetic that blocks sodium channels in nerve cell membranes, inhibiting nerve impulse conduction and providing prolonged analgesia.
Lidocaine is a sodium channel blocker that stabilizes neuronal membranes and inhibits action potentials, providing local anesthesia. Epinephrine is an alpha- and beta-adrenergic agonist that causes vasoconstriction, prolonging lidocaine's effect and reducing systemic absorption.
Local infiltration: up to 266 mg (20 mL) as a single dose; interscalene brachial plexus block: up to 133 mg (10 mL); femoral nerve block: up to 133 mg (10 mL). Maximum dose 266 mg. Administer via slow injection with frequent aspiration.
Local anesthesia: 1% or 2% solution with epinephrine 1:100,000 or 1:200,000; maximum dose 7 mg/kg lidocaine (500 mg) in adults; administer by infiltration or nerve block, not to exceed 1 hour between doses.
None Documented
None Documented
Terminal elimination half-life is 12-48 hours (mean ~24 hours), reflecting prolonged release from the multivesicular liposome depot.
Lidocaine: terminal elimination half-life is approximately 1.5–2.0 hours. With continuous infusion or hepatic impairment, half-life may be prolonged (up to 4–6 hours). Epinephrine: plasma half-life is about 2–3 minutes due to rapid uptake and metabolism.
Renal (approximately 96% as metabolites, <10% unchanged). Biliary/fecal excretion is negligible.
Lidocaine is primarily metabolized in the liver; approximately 90% of a dose is excreted in the urine as metabolites (including monoethylglycinexylidide and glycinexylidide), with less than 10% excreted unchanged. Epinephrine is metabolized by catechol-O-methyltransferase and monoamine oxidase, with metabolites excreted in urine.
Category C
Category A/B
Local Anesthetic
Local Anesthetic / Antiarrhythmic (Class Ib)