Lidocaine Hydrochloride Oral Topical Solution
» Lidocaine Hydrochloride Oral Topical Solution contains not less than 95.0 percent and not more than 105.0 percent of the labeled amount of lidocaine hydrochloride (C14H22N2O·HCl). It contains a suitable flavor and/or sweetening agent.
Packaging and storage— Preserve in tight containers.
USP Reference standards 11—
USP Lidocaine RS Click to View Structure
Identification— Place in a separator a volume of Oral Topical Solution, equivalent to about 300 mg of lidocaine hydrochloride, and extract with four 15-mL portions of chloroform, discarding the chloroform extracts. Add 2 mL of 2 N sodium hydroxide to the aqueous solution remaining in the separator, and extract with four 15-mL portions of chloroform. Combine the chloroform extracts, and evaporate with the aid of a current of warm air to dryness. Dissolve the crystals so obtained in solvent hexane, evaporate with the aid of warm air, and dry the residue in vacuum over silica gel for 24 hours: the residue so obtained responds to Identification test A under Lidocaine.
pH 791: between 5.0 and 7.0.
Assay—
Mobile phase, Standard preparation, and Resolution preparation— Prepare as directed in the Assay for lidocaine hydrochloride under Lidocaine and Epinephrine Injection.
Assay preparation— Transfer an accurately measured volume of Oral Topical Solution, equivalent to about 100 mg of lidocaine hydrochloride, to a 50-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay for lidocaine hydrochloride under Lidocaine and Epinephrine Injection. Calculate the quantity, in mg, of lidocaine hydrochloride (C14H22N2O·HCl) in each mL of the Oral Topical Solution taken by the formula:
(270.80 / 234.34)(50)(C / V)(rU / rS)
in which V is the volume, in mL, of Oral Topical Solution taken; and the other terms are as defined therein.
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Topic/Question Contact Expert Committee
Monograph Mary S. Waddell
Scientific Liaison
1-301-816-8124		 (SM42010) Monographs - Small Molecules 4
Reference Standards RS Technical Services
1-301-816-8129
rstech@usp.org
USP35–NF30 Page 3684