Comparative Pharmacology
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE W EPINEPHRINE versus XYLOCAINE.
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE W EPINEPHRINE versus XYLOCAINE.
LIDOCAINE HYDROCHLORIDE W/ EPINEPHRINE vs XYLOCAINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Lidocaine is a sodium channel blocker that inhibits voltage-gated sodium channels, preventing depolarization and conduction of nerve impulses. Epinephrine is an alpha- and beta-adrenergic agonist that causes vasoconstriction, reducing systemic absorption of lidocaine and prolonging local anesthetic effect.
Lidocaine binds to and inhibits voltage-gated sodium channels in the neuronal membrane, stabilizing the membrane and preventing the initiation and conduction of nerve impulses, thereby producing local anesthesia.
Local anesthesia: 1-5 mL of 1% or 2% solution with epinephrine 1:100,000 or 1:200,000; maximum dose 7 mg/kg lidocaine (500 mg without epinephrine, 7 mg/kg with epinephrine) per procedure. Intravenous: 1-1.5 mg/kg bolus for ventricular arrhythmias, followed by continuous infusion 1-4 mg/min.
1-5 mg/kg (max 300 mg) local infiltration; epidural: 1-2% solution, 5-20 mL.
None Documented
None Documented
Terminal half-life 1.5-2 hours (single dose), prolonged to 2-3 hours with continuous infusion; in heart failure or hepatic cirrhosis, half-life may exceed 5 hours.
Terminal elimination half-life is approximately 1.5 to 2 hours in adults, prolonged to 2-3 hours in patients with hepatic impairment, and may exceed 5 hours in neonates or patients with heart failure.
Renal: unchanged drug <10%, major metabolites (MEGX and GX) ~70% renal; biliary: <10% fecal; total clearance ~10-20 mL/min/kg. Renal impairment prolongs elimination of metabolites.
Hepatic metabolism (primarily by CYP1A2 and CYP3A4) to metabolites, mainly monoethylglycinexylidide (MEGX) and glycinexylidide (GX); less than 10% excreted unchanged in urine. Renal excretion of metabolites: MEGX (70-80%) and GX (10-20%). Biliary/fecal elimination is minimal.
Category A/B
Category C
Local Anesthetic / Antiarrhythmic (Class Ib)
Local Anesthetic