Neomycin Sulfate and Dexamethasone Sodium Phosphate Ophthalmic Ointment
» Neomycin Sulfate and Dexamethasone Sodium Phosphate Ophthalmic Ointment is a sterile ointment containing Neomycin Sulfate and Dexamethasone Sodium Phosphate. It contains the equivalent of not less than 90.0 percent and not more than 135.0 percent of the labeled amount of neomycin, and the equivalent of not less than 90.0 percent and not more than 110.0 percent of the labeled amount of dexamethasone phosphate (C22H30FO8P).
[noteWhere Neomycin Sulfate and Dexamethasone Sodium Phosphate Ophthalmic Ointment is prescribed without reference to the quantity of neomycin or dexamethasone phosphate contained therein, a product containing 3.5 mg of neomycin and 0.5 mg of dexamethasone phosphate per g shall be dispensed. ]
Packaging and storage Preserve in collapsible ophthalmic ointment tubes.
USP Reference standards 11
USP Neomycin Sulfate RS
A: It meets the requirements for neomycin under Thin-Layer Chromatographic Identification Test 201BNP.
B: The Assay preparation, prepared as directed in the Assay for dexamethasone phosphate, meets the requirements for the Identification test under Dexamethasone Sodium Phosphate Cream.
Sterility 71: meets the requirements.
Minimum fill 755: meets the requirements.
Water, Method I 921: not more than 1.0%, 20 mL of a mixture of toluene and methanol (7:3) being used in place of methanol in the titration vessel.
Metal particles It meets the requirements of the test for Metal Particles in Ophthalmic Ointments 751.
Assay for neomycin Proceed as directed under AntibioticsMicrobial Assays 81, using an accurately weighed portion of Ophthalmic Ointment shaken in a separator with about 50 mL of ether, and extracted with four 20-mL portions of Buffer No. 3. Combine the aqueous extracts, and dilute with Buffer No. 3 to an appropriate volume to obtain a stock solution. Dilute this stock solution quantitatively and stepwise with Buffer No. 3 to obtain a Test Dilution having a concentration assumed to be equal to the median dose level of the Standard.
Assay for dexamethasone phosphate
Alcoholaqueous phosphate buffer, 0.05 M Phosphate buffer, Mobile phase, Standard preparation, and Chromatographic system Prepare as directed in the Assay under Dexamethasone Sodium Phosphate Cream.
Assay preparation Using an accurately weighed portion of Ophthalmic Ointment, prepare as directed in the Assay under Dexamethasone Sodium Phosphate Cream.
Procedure Proceed as directed for Procedure in the Assay under Dexamethasone Sodium Phosphate Cream. Calculate the quantity, in mg, of dexamethasone phosphate (C22H30FO8P) in the portion of Ophthalmic Ointment taken by the formula:
0.1C(rU / rS).
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USP35NF30 Page 4012Pharmacopeial Forum: Volume No. 28(4) Page 1154