Lidocaine Hydrochloride Oral Topical Solution
»Lidocaine Hydrochloride Oral Topical Solution contains not less than 95.0percent and not more than 105.0percent 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.
Identification— Place in a separator a volume of Oral Topical Solution,equivalent to about 300mg of lidocaine hydrochloride,and extract with four 15-mLportions of chloroform,discarding the chloroform extracts.Add 2mLof 2Nsodium hydroxide to the aqueous solution remaining in the separator,and extract with four 15-mLportions 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 24hours:the residue so obtained responds to Identificationtest Aunder Lidocaine.
pHá791ñ: between 5.0and 7.0.
Assay—
Mobile phase,Standard preparation,andResolution preparation— Prepare as directed in the Assay for lidocaine hydrochlorideunder Lidocaine and Epinephrine Injection.
Assay preparation— Transfer an accurately measured volume of Oral Topical Solution,equivalent to about 100mg of lidocaine hydrochloride,to a 50-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.
Procedure— Proceed as directed for Procedurein the Assay for lidocaine hydrochlorideunder Lidocaine and Epinephrine Injection.Calculate the quantity,in mg,of lidocaine hydrochloride (C14H22N2O·HCl)in each mLof the Oral Topical Solution taken by the formula:
(270.80/234.34)(50)(C/V)(rU/rS),
in which Vis the volume,in mL,of Oral Topical Solution taken;and the other terms are as defined therein.
Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 1131
Phone Number:1-301-816-8379