Comparative Pharmacology
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE.
Head-to-head clinical analysis: EMLA versus LIDOCAINE HYDROCHLORIDE.
EMLA vs LIDOCAINE HYDROCHLORIDE
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 hydrochloride is a sodium channel blocker that inhibits voltage-gated sodium channels in neuronal and cardiac cell membranes, stabilizing the membrane and preventing depolarization, thereby blocking nerve impulses and exerting local anesthetic and antiarrhythmic effects.
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.
IV: 1-1.5 mg/kg bolus, then 1-4 mg/min continuous infusion. Max: 3 mg/kg (300 mg) loading dose. For ventricular arrhythmias.
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 1.5–2 hours in adults. In patients with heart failure, hepatic cirrhosis, or those on CYP-inhibitors, half-life may be prolonged to ≥3 hours; in neonates, up to 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.
Primarily hepatic metabolism (90% CYP3A4, also CYP1A2) to inactive metabolites (monoethylglycinexylidide, glycinexylidide); <10% excreted unchanged in urine. Renal elimination accounts for the majority of metabolite clearance.
Category C
Category A/B
Local Anesthetic
Local Anesthetic / Antiarrhythmic (Class Ib)