Formulation, Development and Evaluation of pH Sensitive In-Situ Fexofenadine Hydrochloride gel for Nasal Administration

Nasal mucosa has been considered as a potential administration route to achieve faster and higher levels of drug absorption because it is permeable to more compounds than the gastrointestinal tract. It is an attractive route of administration due to lack of pancreatic and gastric enzymatic activity, neutral pH of the nasal mucus and less dilution by gastrointestinal contents. In-situ gel forming systems have been developed to prolong the nasal residence time of a drug and improve nasal bioavailability. Fexofenadine hydrochloride is one of the most widely used drugs for allergic rhinitis. It is an anti-histaminic and is available in oral dosage forms. The present work is aimed at designing a gel formula for nasal administration. To enhance therapeutic effect of the nasal formulation of fexofenadine hydrochloride pH sensitive polymers were used. Xanthan gum and Carbopol 934 were selected as independent variables in the factorial design. Solubility of the drug in the formulation was enhanced by using Tween 80. Evaluation parameters of the formulation like pH, clarity; rheological study both formulation i.e. solution and performed gel, gelling time, drug content, in-vitro drug diffusion study, stability studies were performed. The formulations so designed shall enhance bioavailability of drug and offer better therapeutic outcomes, offer aesthetically appealing dosage form to increase patient compliance and shall overcome side effects and limitations of other dosage forms of marketed preparations.