Development of an In-situ Nasal Gel Formulation of Bepotastine Besilate for the Treatment of Allergic Rhinitis

The objective of this research was to formulate and evaluate mucoadhesive in situ nasal gels as a novel delivery system for Bepotastine Besilate. Aiming to provide sustained drug release directly at the site of action, thereby reducing the need for frequent dosing due to the drug's rapid absorption and short half-life. A series of eight formulations were developed using varying ratios of Poloxamer 407 and Poloxamer 188. The formulations exhibited a visually clear sol phase, indicating uniform dispersion of ingredients, with gelling temperatures ranging from 33.3±0.41 to 36.7±0.73°C. The gelling time, an important parameter for user convenience and efficacy, ranged from 15.7±01.52 to 43.3±20.80 s, meeting practical application requirements. Furthermore, all formulations consistently achieved a drug content of over 95%, ensuring dosage uniformity and efficacy. The pH values of the formulations were within the acceptable range of 6.13±0.10 to 6.91±0.02, minimizing the risk of mucosal irritation upon application. Importantly, the mucoadhesive strength ranged from 1056±0.32 to 6456± 045 dyne/cm², indicating robust adhesion to nasal mucosa, which is critical for prolonged drug retention and sustained release. In vitro drug release studies demonstrated sustained release profiles exceeding 4 hours for all formulations, following Higuchi kinetics, suggesting controlled drug release from the gel matrix. Accelerated stability studies corroborated the formulations' stability over the test period, indicating their potential for long-term storage and commercial viability. Additionally, FTIR analysis revealed no evidence of drug-polymer interactions, confirming the compatibility of Bepotastine Besilate with the selected polymer matrix. These comprehensive findings support the potential of in situ nasal gels as an effective and promising strategy for enhancing the therapeutic efficacy of Bepotastine Besilate, thereby improving patient outcomes.