Edition: BP 2025 (Ph. Eur. 11.6 update)
General Notices
Action and use
Adrenoceptor agonist.
DEFINITION
Ephedrine Nasal Drops are a solution of Ephedrine Hydrochloride in a suitable aqueous vehicle.
The nasal drops comply with the requirements stated under Nasal Preparations and with the following requirements.
Content of ephedrine hydrochloride, C10H15NO,HCl
95.0 to 105.0% of the stated amount.
IDENTIFICATION
A. To a quantity of the nasal drops containing 0.1 g of Ephedrine Hydrochloride add 2 mL of 2M hydrochloric acid, shake with two 20 mL quantities of chloroform and discard the chloroform. Add 5M ammonia until the aqueous layer is alkaline, extract with two 30 mL quantities of a mixture of 3 volumes of chloroform and 1 volume of ethanol, dry the combined extracts over anhydrous sodium sulfate, filter and evaporate to dryness at a pressure of 2 kPa, heating gently to remove the last traces of solvent. The infrared absorption spectrum of the residue, Appendix II A, is concordant with the reference spectrum of ephedrine (RS 121).
B. In the test for Related substances, the principal spot in the chromatogram obtained with solution (2) corresponds to that in the chromatogram obtained with solution (4).
TESTS
Acidity or alkalinity
pH, 4.0 to 7.0, Appendix V L.
Related substances
Carry out the method for thin-layer chromatography, Appendix III A, using a silica gel precoated plate (Merck silica gel 60 plates are suitable) and a mixture of 80 volumes of propan-2-ol, 15 volumes of 13.5M ammonia and 5 volumes of chloroform as the mobile phase. Apply separately to the plate 20 µL of each of the following solutions. For solution (1) use the nasal drops diluted, if necessary, with water to contain 0.5% w/v of Ephedrine Hydrochloride. For solution (2) dilute 1 volume of solution (1) to 5 volumes with methanol. For solution (3) dilute 1 volume of solution (1) to 200 volumes with water. Solution (4) contains 0.1% w/v of ephedrine hydrochloride BPCRS in methanol. After removal of the plate, allow it to dry in air, spray with ninhydrin solution and heat at 100° for 5 minutes. Any secondary spot in the chromatogram obtained with solution (1) is not more intense than the spot in the chromatogram obtained with solution (3). Disregard any spot of lighter colour than the background and any spot remaining on the line of application.
ASSAY
Carry out the method for liquid chromatography, Appendix III D, using the following solutions. Solution (1) is a 0.1% w/v solution of ephedrine hydrochloride BPCRS in methanol (65%). For solution (2) dilute the nasal drops with methanol (80%) to contain 0.1% w/v of Ephedrine Hydrochloride.
The chromatographic procedure may be carried out using (a) a stainless steel column (20 cm × 4.6 mm) packed with end-capped octadecylsilyl silica gel for chromatography (10 µm) (Nucleosil C18 is suitable), (b) 0.005M dioctyl sodium sulfosuccinate in a mixture of 65 volumes of methanol, 35 volumes of water and 1 volume of glacial acetic acid as the mobile phase with a flow rate of 2 mL per minute and (c) a detection wavelength of 263 nm.
Calculate the content of C10H15NO,HCl in the nasal drops using the declared content of C10H15NO,HCl in ephedrine hydrochloride BPCRS.
When ephedrine nasal drops are prescribed or demanded no strength being stated, nasal drops containing 0.5% w/v of ephedrine hydrochloride shall be dispensed or supplied.
