Comparative Pharmacology
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE PRESERVATIVE FREE versus POSIMIR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LIDOCAINE HYDROCHLORIDE PRESERVATIVE FREE versus POSIMIR.
LIDOCAINE HYDROCHLORIDE PRESERVATIVE FREE vs POSIMIR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Lidocaine is a local anesthetic that stabilizes the neuronal membrane by inhibiting sodium ion channels, thereby blocking the initiation and conduction of nerve impulses. It also exhibits cardiac effects as a class IB antiarrhythmic agent by modulating sodium channels in myocardial cells.
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.
1-4 mg/kg via intravenous bolus, not to exceed 300 mg; may be followed by continuous infusion of 1-4 mg/min.
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
1.5–2 hours (terminal) in healthy adults; prolonged in hepatic impairment (up to 5–7 hours), heart failure (up to 10 hours), or with continuous infusion (>24 h) due to accumulation. Context: requires monitoring in hepatic or cardiac dysfunction to avoid toxicity.
Terminal elimination half-life is approximately 27 hours (range 16-38 hours), supporting once-daily dosing in clinical use.
Renal: ~90% as metabolites (primarily monoethylglycinexylidide [MEGX] and glycinexylidide [GX]), <10% unchanged. Fecal: <1%.
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