DESCRIPTION

Xylocaine (lidocaine HCl) Injections are sterile, nonpyrogenic, aqueous solutions that contain a local anesthetic agent with or without epinephrine and are administered parenterally by injection. See INDICATIONS for specific uses.

Xylocaine solutions contain lidocaine HCl, which is chemically designated as acetamide, 2-(diethylamino)-N-(2,6- dimethylphenyl)-, monohydrochloride and has the molecular wt. 270.8. Lidocaine HCl (C14H22N2O • HCl) has the following structural formula:

Lidocaine Chemical Structure

Epinephrine is (-) -3, 4-Dihydroxy-α-[(methylamino) methyl] benzyl alcohol and has the molecular wt. 183.21. Epinephrine (C9H13NO3) has the following structural formula:

Epinephrine Chemical Structure

Dosage forms listed as Xylocaine-MPF indicate single dose solutions that are Methyl Paraben Free (MPF).

Xylocaine MPF is a sterile, nonpyrogenic, isotonic solution containing sodium chloride. Xylocaine in multiple dose vials: Each mL also contains 1 mg methylparaben as antiseptic preservative. The pH of these solutions is adjusted to approximately 6.5 (5.0-7.0) with sodium hydroxide and/or hydrochloric acid.

Xylocaine MPF with Epinephrine is a sterile, nonpyrogenic, isotonic solution containing sodium chloride. Each mL contains lidocaine hydrochloride and epinephrine, with 0.5 mg sodium metabisulfite as an antioxidant and 0.2 mg citric acid as a stabilizer. Xylocaine with Epinephrine in multiple dose vials: Each mL also contains 1 mg methylparaben as antiseptic preservative. The pH of these solutions is adjusted to approximately 4.5(3.3-5.5) with sodium hydroxide and/or hydrochloric acid. Filled under nitrogen.

CLINICAL PHARMACOLOGY

Mechanism of Action:

Lidocaine HCl stabilizes the neuronal membrane by inhibiting the ionic fluxes required for the initiation and conduction of impulses thereby effecting local anesthetic action.

Hemodynamics:

Excessive blood levels may cause changes in cardiac output, total peripheral resistance, and mean arterial pressure. With central neural blockade these changes may be attributable to block of autonomic fibers, a direct depressant effect of the local anesthetic agent on various components of the cardiovascular system, and/or the beta-adrenergic receptor stimulating action of epinephrine when present. The net effect is normally a modest hypotension when the recommended dosages are not exceeded.