Comparative Pharmacology
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE IN PLASTIC CONTAINER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE IN PLASTIC CONTAINER.
EMLA vs LIDOCAINE HYDROCHLORIDE IN PLASTIC CONTAINER
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.
Blocks voltage-gated sodium channels, inhibiting action potential propagation in neurons and cardiac myocytes.
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.
1-1.5 mg/kg IV bolus, then 0.5-0.75 mg/kg IV bolus every 5-10 min to a max of 3 mg/kg total loading dose; maintenance infusion 1-4 mg/min IV. For epidural: 5-10 mL of 1-2% solution.
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: 1.5–2 hours (single dose); prolonged to 2–3 hours with repeated dosing or in heart failure, liver disease, or elderly. Context: Effective for 1–2 hours after IV bolus, requiring infusion for sustained effect.
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 excretion of unchanged drug and metabolites: ~90% as metabolites (e.g., monoethylglycinexylidide, glycinexylidide), <10% unchanged. Biliary/fecal: minimal (<1%).
Category C
Category A/B
Local Anesthetic
Local Anesthetic / Antiarrhythmic (Class Ib)