Comparative Pharmacology
Head-to-head clinical analysis: SYNERA versus XYLOCAINE PRESERVATIVE FREE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SYNERA versus XYLOCAINE PRESERVATIVE FREE.
SYNERA vs XYLOCAINE PRESERVATIVE FREE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
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.
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.
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: 1.5–2 hours; prilocaine: 1–1.5 hours. Terminal half-life similar for both. Note: prolonged in hepatic impairment or neonates.
Terminal elimination half-life approximately 1.5-2 hours in adults; prolonged in hepatic impairment (up to 3-4 hours) and congestive heart failure.
Renal excretion of lidocaine and prilocaine metabolites: lidocaine <10% unchanged, prilocaine negligible unchanged. Metabolites primarily renal.
Renal excretion of metabolites (90-95% as metabolites, <5% unchanged); biliary/fecal excretion minimal (<1%).
Category C
Category C
Local Anesthetic
Local Anesthetic