Tetracaine Ophthalmic Ointment »Tetracaine Ophthalmic Ointment is a sterile ointment containing not less than 0.45percent and not more than 0.55percent of C15H24N2O2in White Petrolatum. Packaging and storage— Preserve in collapsible ophthalmic ointment tubes. USP Reference standards á11ñ USP Tetracaine Hydrochloride RS. Identification— A: The solution employed for measurement of absorbance in the Assayexhibits a maximum at 310±2nm. B: Dissolve 5g in 50mLof ether,extract the ether solution with 5mLof 3Nhydrochloric acid,and filter the extract.To the extract add 2mLof potassium thiocyanate solution (1in 2):a crystalline precipitate is formed,and when recrystallized from water and dried at 80for 2hours,it melts between 130and 132(see Melting Range or Temperature á741ñ). Sterility á71ñ: meets the requirements . Minimum fill á755ñ: meets the requirements. Metal particles— It meets the requirements of the test for Metal Particles in Ophthalmic Ointments á751ñ. Assay— Standard preparation— Prepare as directed in the Assayunder Tetracaine Ointment. Assay preparation— Using an accurately weighed portion of Ophthalmic Ointment,prepare as directed in the Assayunder Tetracaine Ointment. Procedure— Proceed as directed for Procedurein the Assayunder Tetracaine Ointment. Auxiliary Information— Staff Liaison:Karen A Russo,Ph.D.,Scientist Expert Committee:(PA1)Pharmaceutical Analysis 1 USP28–NF23Page 1880 Phone Number:1-301-816-8379