Quality Standard for Diphenhydramine and Ephedrine Nasal Drops

Objective To establish a method for quality control of Diphenhydramine and Ephedrine Nasal Drops. Methods The chromatographic conditions included the CN column( 200 mm × 4. 6 mm,5 μm) and acetonitrilewater-triethylamine( 50∶ 50∶ 0. 5)( the pH was adjusted to 6. 5 with glacial acetic acid) as the mobile phase,The flow rate was 1. 0 ml·min- 1and monitored at 258 nm. Results Diphenhydramine hydrochloride and ephedrine hydrochloride were identified by chemical reaction methods and HPLC. They were well separated. The calibration curve of diphenhydramine hydrochloride and ephedrine hydrochloride was linear in the range of 0. 0499- 0. 3996 mg·ml- 1( r =0. 9999,n = 5) and 0. 2000- 1. 6002 mg·ml- 1( r =0.9999,n =5). The average recovery was 100.0% with an RSD of 0. 4%( n = 9) and 99. 68% with an RSD of 0. 4%( n = 9) respectively. Conclusion This method is accurate and reproducible. It can be used as a reliable method for quality control of Diphenhydramine and Ephedrine Nasal Drops.