Comparative Pharmacology
Head-to-head clinical analysis: SYNERA versus TETRACAINE HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SYNERA versus TETRACAINE HYDROCHLORIDE.
SYNERA vs TETRACAINE HYDROCHLORIDE
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.
Tetracaine hydrochloride is a local anesthetic of the ester type that reversibly blocks nerve conduction by decreasing sodium ion permeability across the neuronal membrane, thereby stabilizing the membrane and preventing the initiation and transmission of nerve impulses.
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.
Topical: 0.5-2% solution or ointment applied to affected area up to 4 times daily as needed. Maximum single dose: 20 mL of 2% solution (400 mg). Spinal anesthesia: 0.5% solution, 2-3 mL (10-15 mg) injected intrathecally.
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 is approximately 1.5–3 minutes in plasma due to rapid hydrolysis; clinical effect duration is dose-dependent (15–30 minutes for topical anesthesia).
Renal excretion of lidocaine and prilocaine metabolites: lidocaine <10% unchanged, prilocaine negligible unchanged. Metabolites primarily renal.
Primarily metabolized by plasma pseudocholinesterase; renal excretion of metabolites accounts for >95% of elimination, with <2% excreted unchanged in urine. Biliary/fecal elimination is negligible.
Category C
Category C
Local Anesthetic
Local Anesthetic