Comparative Pharmacology
Head-to-head clinical analysis: EMLA versus EXPAREL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMLA versus EXPAREL.
EMLA vs EXPAREL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
EMLA is a eutectic mixture of lidocaine 2.5% and prilocaine 2.5%. Lidocaine and prilocaine are amide-type local anesthetics that block sodium ion channels in neuronal membranes, inhibiting the initiation and conduction of nerve impulses, thereby producing local analgesia.
Liposomal bupivacaine is a local anesthetic that blocks sodium channels in nerve cell membranes, inhibiting nerve impulse conduction and providing prolonged analgesia.
Apply a thick layer of cream (approximately 2.5 g per 20 cm²) to intact skin under an occlusive dressing for at least 1 hour for minor procedures; for dermal procedures on larger areas, apply up to 60 minutes before procedure, maximum single application area of 600 cm² in adults.
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.
None Documented
None Documented
After topical application, the terminal elimination half-life of lidocaine is approximately 1.5-2 hours; prilocaine half-life is approximately 1.5 hours. In neonates, half-life may be prolonged due to immature hepatic function. Clinical context: Steady state is achieved within 12-24 hours with repeated application.
Terminal elimination half-life is 12-48 hours (mean ~24 hours), reflecting prolonged release from the multivesicular liposome depot.
Lidocaine and prilocaine are metabolized in the liver; lidocaine metabolites (primarily 4-hydroxyxylidine) and prilocaine metabolites (primarily o-toluidine) are excreted renally. Less than 5% of unchanged lidocaine and prilocaine are excreted unchanged in urine. Fecal excretion is negligible.
Renal (approximately 96% as metabolites, <10% unchanged). Biliary/fecal excretion is negligible.
Category C
Category C
Local Anesthetic
Local Anesthetic