Comparative Pharmacology
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE W EPINEPHRINE versus SYNERA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE W EPINEPHRINE versus SYNERA.
LIDOCAINE HYDROCHLORIDE W/ EPINEPHRINE vs SYNERA
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 is an amide-type local anesthetic that stabilizes neuronal membranes by inhibiting sodium ion influx, thereby blocking nerve impulse initiation and conduction. Tetracaine is an ester-type local anesthetic that similarly inhibits sodium channels. The combination provides local dermal 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.
Apply 1 patch (70 mg lidocaine and 70 mg tetracaine) to intact skin over the intended venipuncture site or superficial dermatologic procedure site 20-30 minutes prior to procedure; maximum 1 patch per procedure.
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.
Lidocaine: 1.5–2 hours; prilocaine: 1–1.5 hours. Terminal half-life similar for both. Note: prolonged in hepatic impairment or neonates.
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.
Renal excretion of lidocaine and prilocaine metabolites: lidocaine <10% unchanged, prilocaine negligible unchanged. Metabolites primarily renal.
Category A/B
Category C
Local Anesthetic / Antiarrhythmic (Class Ib)
Local Anesthetic