Comparative Pharmacology
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE 0 4 IN DEXTROSE 5.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE 0 4 IN DEXTROSE 5.
EMLA vs LIDOCAINE HYDROCHLORIDE 0.4% IN DEXTROSE 5%
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.
Lidocaine is a class IB antiarrhythmic agent that blocks voltage-gated sodium channels, inhibiting phase 0 depolarization and decreasing automaticity in ventricular myocardial cells. It also has local anesthetic properties by blocking nerve impulse conduction.
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.
Intravenous infusion: 1-4 mg/min (0.25-1 mL/min of 0.4% solution) after a loading dose of 1-1.5 mg/kg IV bolus for ventricular arrhythmias. Maximum total dose: 3 mg/kg.
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 approximately 1.5-2 hours (mean 1.8 h) in healthy adults. In patients with hepatic impairment or heart failure, half-life may be prolonged to >3 hours. In neonates, half-life can be 3-6 hours.
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 metabolites (primarily monoethylglycinexylidide and glycinexylidide) accounts for >90% of elimination. Less than 10% excreted unchanged in urine. Biliary/fecal excretion is negligible.
Category C
Category A/B
Local Anesthetic
Local Anesthetic / Antiarrhythmic (Class Ib)