Comparative Pharmacology
Head-to-head clinical analysis: SYNERA versus XYLOCAINE 4 PRESERVATIVE FREE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SYNERA versus XYLOCAINE 4 PRESERVATIVE FREE.
SYNERA vs XYLOCAINE 4% 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 through voltage-gated sodium channels, thereby blocking the initiation and propagation of action potentials, resulting in local anesthesia.
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.
Maximum 4.5 mg/kg (not to exceed 300 mg) via subcutaneous infiltration, epidural, or nerve block; repeat dosing after 30 minutes if needed.
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: ~1.5–2 hours (adults). Prolonged in hepatic impairment, congestive heart failure, or neonates.
Renal excretion of lidocaine and prilocaine metabolites: lidocaine <10% unchanged, prilocaine negligible unchanged. Metabolites primarily renal.
Renal: ~90% as metabolites (mostly 4-hydroxy-2,6-xylidine and conjugates); <10% unchanged. Biliary/fecal: minor.
Category C
Category C
Local Anesthetic
Local Anesthetic