Hydrocortisone Acetate and Neomycin Ear Drops

Hydrocortisone and Neomycin Ear Drops

Corticosteroid + Aminoglycoside antibacterial.

Hydrocortisone Acetate and Neomycin Ear Drops are a suspension of Hydrocortisone Acetate in a solution of Neomycin Sulfate in Purified Water.

The ear drops comply with the requirements stated under Ear Preparations and with the following requirements.

90.0 to 110.0% w/v of the stated amount.

A. Comply with test A for Identification described under Hydrocortisone and Neomycin Cream using the following solutions. For solution (1) add 10 mL of chloroform to a quantity of the ear drops containing 5 mg of Hydrocortisone Acetate in a separating funnel, shake for 2 to 3 minutes and allow the layers to separate. Filter if necessary and use the chloroform layer. Solution (2) contains 0.05% w/v of hydrocortisone acetate BPCRS in chloroform.

B. In the Assay for hydrocortisone acetate the chromatogram obtained with solution (3) shows a peak with the same retention time as the peak due to hydrocortisone acetate in the chromatogram obtained with solution (1).

C. Comply with test C for Identification described under Hydrocortisone and Neomycin Cream. For solution (1) dilute a volume containing 3500 IU of Neomycin Sulfate with water to 2.5 mL, shake with 3 mL of chloroform, centrifuge and use the clear, upper layer.

pH, 6.5 to 8.0, Appendix V L.

Comply with the test described under Hydrocortisone and Neomycin Cream. For solution (1) dilute a volume containing 3500 IU of Neomycin Sulfate with 2.5 mL of water, shake gently with 3 mL of chloroform, centrifuge and use the aqueous layer.

Comply with the test described under Hydrocortisone and Neomycin Cream but using as solution (2) a solution prepared in the following manner. Dilute the ear drops with 0.02m sodium tetraborate to contain 700 IU per mL. To 0.5 mL of the resulting solution add 1.5 mL of a freshly prepared 2% w/v solution of 1-fluoro-2,4-dinitrobenzene in methanol, heat in a water bath at 60° for 1 hour, cool and dilute the solution to 25 mL with the mobile phase; allow to stand and use the clear, lower layer.

Carry out the method for liquid chromatography, Appendix III D, using the following solutions. Solution (1) contains 0.020% w/v of hydrocortisone acetate BPCRS and 0.016% w/v of fluoxymesterone BPCRS (internal standard) in chloroform. For solution (2) shake a quantity of the ear drops containing 10 mg of Hydrocortisone Acetate with 25 mL of a 0.032% w/v solution of fluoxymesterone BPCRS in chloroform, add 25 mL of chloroform, mix and filter through anhydrous sodium sulfate.

The chromatographic procedure may be carried out using (a) a stainless steel column (30 cm × 3.9 mm) packed with silica gel for chromatography (10 µm) (µPorasil is suitable), (b) a mixture of 425 volumes of butyl chloride, 425 volumes of butyl chloride saturated with water, 70 volumes of tetrahydrofuran, 35 volumes of methanol and 30 volumes of glacial acetic acid as the mobile phase with a flow rate of 1 mL per minute and (c) a detection wavelength of 254 nm.

Calculate the content of C₂₃H₃₂O₆ in the ear drops using the declared content of C₂₃H₃₂O₆ in hydrocortisone acetate BPCRS.

Dilute a volume containing 3500 IU to 50 mL with sterile phosphate buffer pH 8.0, dilute 10 mL of the resulting solution to 100 mL with the same solvent and carry out the microbiological assay of antibiotics, Appendix XIV A. The precision of the assay is such that the fiducial limits of error are not less than 95% and not more than 105% of the estimated potency. The upper fiducial limit of error is not less than 90.0% and the lower fiducial limit of error is not more than 115.0% of the stated number of IU per mL.

The strength with respect to Neomycin Sulfate is stated as the number of IU (Units) per mL.