Comparative Pharmacology
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE versus XYLOCAINE PRESERVATIVE FREE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE versus XYLOCAINE PRESERVATIVE FREE.
LIDOCAINE HYDROCHLORIDE AND EPINEPHRINE vs XYLOCAINE PRESERVATIVE FREE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Lidocaine is a sodium channel blocker that stabilizes neuronal membranes and inhibits action potentials, providing local anesthesia. Epinephrine is an alpha- and beta-adrenergic agonist that causes vasoconstriction, prolonging lidocaine's effect and reducing systemic absorption.
Lidocaine stabilizes the neuronal membrane by inhibiting sodium ion influx, thereby blocking impulse initiation and conduction. It binds to voltage-gated sodium channels in the inactivated state, preventing depolarization and propagation of action potentials.
Local anesthesia: 1% or 2% solution with epinephrine 1:100,000 or 1:200,000; maximum dose 7 mg/kg lidocaine (500 mg) in adults; administer by infiltration or nerve block, not to exceed 1 hour between doses.
Adult dose: 1-30 mL of 1% or 2% solution (10-600 mg) via subcutaneous infiltration, peripheral nerve block, or epidural; max 4.5 mg/kg (300 mg without epinephrine, 7 mg/kg [500 mg] with epinephrine) per 2-hour period.
None Documented
None Documented
Lidocaine: terminal elimination half-life is approximately 1.5–2.0 hours. With continuous infusion or hepatic impairment, half-life may be prolonged (up to 4–6 hours). Epinephrine: plasma half-life is about 2–3 minutes due to rapid uptake and metabolism.
Terminal elimination half-life approximately 1.5-2 hours in adults; prolonged in hepatic impairment (up to 3-4 hours) and congestive heart failure.
Lidocaine is primarily metabolized in the liver; approximately 90% of a dose is excreted in the urine as metabolites (including monoethylglycinexylidide and glycinexylidide), with less than 10% excreted unchanged. Epinephrine is metabolized by catechol-O-methyltransferase and monoamine oxidase, with metabolites excreted in urine.
Renal excretion of metabolites (90-95% as metabolites, <5% unchanged); biliary/fecal excretion minimal (<1%).
Category A/B
Category C
Local Anesthetic / Antiarrhythmic (Class Ib)
Local Anesthetic