Simultaneous assaying of famotidine, calcium carbonate and magnesium hydroxide in the extemporaneously prepared suspension

Abstract

INTRODUCTION: The share of extemporaneously prepared drugs on the pharmaceutical market has been on the increase lately. The suspension of famotidine with calcium carbonate and magnesium hydrox- ide is one of such drugs. AIM: The aim of our study is to develop the assay methods for each component in the simultaneous sample of the suspension in order to decrease the volume of the medical form and the time for analysis. MATERIALS AND METHODS: The object of study is the extemporaneously prepared suspension with the content of active substances per 5 ml: famotidine 10 mg; calcium carbonate 400 mg; magnesium hydrox- ide 120 mg. Tablets with famotidine content (20 mg) were used for suspension preparation. The substance of famotidine was used as the working standard sample (WSS). The `Evolution 60S` spectro- photometer, the AB 204 S/A Mettler Toledo analytical balances, class A measuring vessels as well as reagents that meet the requirements of the State Pharmacopeia of Ukraine were used in the study. RESULTS: Complexometric titration for calcium carbonate and magnesium hydroxide using murexide and Eriochrome Black T as indicators and UV-spectrophotometric determination of famotidine at I»max=265 nm wavelength were carried out in the simultaneous sample of the suspension. The metrological character- istics confirm the correctness of the proposed methods. CONCLUSIONS: The developed methods can be used to determine the active compounds in the simultane- ous sample of the suspension. The uncertainty of the average results for calcium carbonate quantitative de- termination was 0.94%, for magnesium hydroxide - 1.14%, and for famotidine - 0.75%.