Comparative Pharmacology
Head-to-head clinical analysis: EMLA versus XYLOCAINE 1 5 W DEXTROSE 7 5.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMLA versus XYLOCAINE 1 5 W DEXTROSE 7 5.
EMLA vs XYLOCAINE 1.5% W/ DEXTROSE 7.5%
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 an amide-type local anesthetic that blocks sodium channels, thereby inhibiting the propagation of action potentials in peripheral nerves, leading to local anesthesia.
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.
Spinal anesthesia: 1.5-2 mL (22.5-30 mg lidocaine) for lower extremity or perineal procedures; 2-3 mL (30-45 mg) for lower abdominal or urological procedures. Administered via lumbar puncture.
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 in adults with normal hepatic function; may be prolonged to 3–5 hours in patients with hepatic impairment or congestive heart failure.
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 (predominantly 4-hydroxy-2,6-xylidine and conjugates) accounts for >80% of elimination; less than 10% eliminated unchanged in urine. Biliary/fecal excretion of metabolites contributes <10%.
Category C
Category C
Local Anesthetic
Local Anesthetic