Tetracaine Hydrochloride Topical Solution »Tetracaine Hydrochloride Topical Solution is an aqueous solution of Tetracaine Hydrochloride.It contains not less than 95.0percent and not more than 105.0percent of the labeled amount of C15H24N2O2·HCl.It contains a suitable antimicrobial agent. Packaging and storage— Preserve in tight,light-resistant containers. Labeling— Label it to indicate that the Topical Solution is not to be used if it contains crystals,or if it is cloudy or discolored. USP Reference standards á11ñ USP Tetracaine Hydrochloride RS. Identification— A:Ultraviolet Absorption á197Uñ Solutions: solutions of the Topical Solution employed for measurement of absorbance in the Assay. B: It responds to the tests for Chloride á191ñ. pHá791ñ: between 4.5and 6.0. Assay— Standard preparation— Prepare as directed in the Assayunder Tetracaine Hydrochloride in Dextrose Injection. Assay preparation— Using an accurately measured volume of Topical Solution,prepare as directed in the Assayunder Tetracaine Hydrochloride in Dextrose Injection. Procedure— Proceed as directed for Procedurein the Assayunder Tetracaine Hydrochloride in Dextrose Injection.Calculate the quantity,in mg,of C15H24N2O2·HCl in the volume of Topical Solution taken by the formula: C(AU/AS), in which Cis the concentration,in µg per mL,of USP Tetracaine Hydrochloride RSin the Standard preparation,and AUand ASare the absorbances of the Assay preparationand the Standard preparation,respectively. Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist Expert Committee:(PA1)Pharmaceutical Analysis 1 USP28–NF23Page 1883 Phone Number:1-301-816-8379