Formulation and Evaluation of Mucoadhesive Microspheres of Desloratadine for Nasal Delivery in Allergy Management

Introduction:: Desloratadine, a widely used antihistamine, suffers from limited oral bioavailability due to significant first-pass metabolism. Nasal delivery offers a promising alternative for rapid onset and improved therapeutic efficacy. Methods:: Desloratadine microspheres were prepared using the emulsificationcrosslinking technique with glutaraldehyde as a cross-linking agent and Span 80 as a stabilizer. Seven batches were formulated by varying polymer and excipient concentrations. Pre-formulation studies included solubility, partition coefficient, micromeritic properties, and FTIR/UV analysis. Post-formulation evaluations covered entrapment efficiency, drug release, particle size, mucoadhesion, and stability. Results:: UV and FTIR confirmed drug identity and compatibility. Desloratadine was poorly water-soluble but showed good solubility in ethanol and methanol. A log P of 1.20 indicated moderate lipophilicity. Particle sizes ranged from 86.1 to 98.4 μm. Batch 7 showed the highest entrapment (85%) and drug loading (31.48%), while Batch 5 exhibited the fastest release (99.2% in 4 h). Batch 6 demonstrated the best mucoadhesion (85.7%) and sustained release. Stability studies showed minimal degradation under stress conditions. Discussion:: Batch 6 achieved an optimal balance, showing sustained release and strong mucoadhesion suitable for nasal retention. The stability results suggest formulation robustness. Overall, nasal microspheres of desloratadine can overcome first-pass metabolism, improve bioavailability, and provide prolonged therapeutic action, supporting their potential as an effective nasal drug delivery system. Conclusion:: Mucoadhesive microspheres of desloratadine provide a stable, effective nasal delivery system with improved retention, drug release, and patient compliance. Batch 6 is optimal for further development.