COMPARATIVE IN VITRO EVALUATION OF BRANDS OF CLOTRIMAZOLE CREAM FORMULATIONS MARKETED IN ETHIOPIA

Abstract

The aim of present work was to undertake comparative in vitro quality evaluation of six marketed clotrimazole cream formulations in Ethiopia with respect to physico-chemical properties like viscosity, spreadability, extrudability, pH and drug content. In vitro clotrimazole release from cream formulations was also studied using synthetic cellulose acetate membrane at 37 ºC in a solvent containing methanol and PBS 7.4 in the ratio of 75:25 as receiver medium. The cumulative amounts of the drug released over 12 h (µg mm-2) were analyzed. All clotrimazole cream formulations showed good and smooth homogeneous appearance with white color. The pH of clotrimazole cream formulations ranged from 4-7, which is a physiologically acceptable pH range and in principle devoid of any skin irritation. Clotrimazole content ranged from 90-110%, ensuring the uniformity of the drug content in all formulations. The increase in diameter of clotrimazole cream formulations following the spreadability test was found to range from 4-6 cm. Cream formulation D (Clotri-Denk) exhibited highest viscosity values than other formulations, whereas formulation E (Chinese Clotrimazole BP) showed lowest viscosity value. Cream formulation F (Mycoril) showed better extrudability and spreadability as compared to other formulations. Drug release from all formulations was slow in the first 6 hrs. After the 6 th hr, steady drug release continued for formulation D and E. Fast drug release was observed in formulations A (Candid) and B (Candigen), whereas for the formulations C (Canesten), D and E, steady drug release pattern was observed after the 6 th hr. It can be concluded that all clotrimazole cream formulations fulfilled the quality criteria of in-house and pharmacopeias specifications.