Comparative Pharmacology
Head-to-head clinical analysis: LIDOCAINE VISCOUS versus POSIMIR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LIDOCAINE VISCOUS versus POSIMIR.
LIDOCAINE VISCOUS vs POSIMIR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Lidocaine is an amide-type local anesthetic that blocks voltage-gated sodium channels (Nav1.7, Nav1.8) in neuronal membranes, inhibiting depolarization and propagation of action potentials, thereby producing local anesthesia. It also has antiarrhythmic properties (class IB) by blocking sodium channels in cardiac myocytes.
Bupivacaine, the active ingredient in POSIMIR, is an amide-type local anesthetic that blocks voltage-gated sodium channels in nerve cell membranes, inhibiting the generation and conduction of nerve impulses. POSIMIR is a bupivacaine extended-release liposomal formulation designed for sustained release at the surgical site.
15 mL (300 mg) orally every 3 hours as needed for pain; maximum 8 doses per 24 hours.
Posimir (bupivacaine) is administered as a single intra-articular injection into the subacromial space following arthroscopic shoulder surgery. The recommended adult dose is 5 mL (66 mg) of the 1.32% solution.
None Documented
None Documented
Terminal elimination half-life is 1.5–2 hours (up to 3 hours in hepatic impairment). Clinically, redistribution half-life (~6 min) determines duration of action after short infusions.
Terminal elimination half-life is approximately 27 hours (range 16-38 hours), supporting once-daily dosing in clinical use.
Renal excretion of unchanged drug and metabolites accounts for >90% of elimination; <10% biliary/fecal. Metabolites include monoethylglycinexylidide (MEGX) and glycinexylidide (GX).
Primarily hepatic metabolism via CYP3A4 and CYP1A2 to inactive metabolites; <5% excreted unchanged in urine. Biliary/fecal excretion accounts for >90% of total clearance.
Category A/B
Category C
Local Anesthetic / Antiarrhythmic (Class Ib)
Local Anesthetic