QUALITY BY DESIGN APPROACH FOR THE DEVELOPMENT AND OPTIMIZATION OF CETIRIZINE HYDROCHLORIDE EMULGEL: FORMULATION, CHARACTERIZATION, AND IN VITRO EVALUATION

Abstract

Emulgels combine the formulation attributes of emulsions and gels and are increasingly investigated as topical drug delivery systems because their rheological and release properties can be tuned through excipient selection. Cetirizine hydrochloride is a second-generation H1-antihistamine that is often used orally. Using Carbopol 940, HPMC K100M, and xanthan gum as gelling agents, the current work created and assessed cetirizine hydrochloride emulgels. A Design of Experiments (DoE) method was then used to optimize the xanthan gum-based system. Preformulation comprised DSC, FTIR, and solubility. The initial emulgels were evaluated for viscosity, drug content, spreadability, extrudability, pH, appearance, and in vitro release. The evaluation of Tween 80, liquid paraffin, and xanthan gum as formulation factors was done using a 2³ factorial design with a single central point, with responses being cumulative drug release and viscosity. Cetirizine hydrochloride and xanthan gum were found to be compatible by FTIR and DSC analysis. The xanthan gum formulation (F3) had the highest drug concentration (91.3 ± 0.50%) and the largest cumulative release over a 6-hour period (94.48 ± 0.45%) among the initial formulations. Xanthan gum concentration was found to be the primary factor influencing both responses by DoE analysis. pH 6.8 ± 0.1, viscosity 9327 ± 12 mPa•s, spreadability 6.4 ± 0.2 g•cm/s, extrudability 172 ± 3 g/cm², drug content 98.2 ± 0.4%, and cumulative drug release 85.3 ± 0.5% were all observed in the stated optimal formulation (F9). During the reported 60-day accelerated stability assessment, the formulation maintained its physical stability. Overall, the results indicate that Cetirizine hydrochloride emulgel based on xanthan gum is a suitable formulation platform.