Advances and Challenges in Buccal Drug Delivery Systems: A Comprehensive Review of Mucoadhesive Technologies, Novel Formulations, and Clinical Applications

Abstract

Buccal drug delivery offers a non-invasive route that bypasses first-pass metabolism and enhances patient compliance. This review highlights recent progress in mucoadhesive polymers, including both traditional and stimuli-responsive materials that improve drug retention and controlled release. Various dosage forms such as tablets, films, sprays, and advanced systems like microneedles and nanofibers are examined for their design and clinical potential. Nanocarrier integration has expanded buccal delivery to include peptides, proteins, and nucleic acids. Key challenges—such as enzymatic degradation, limited permeability, and patient adherence—are discussed alongside regulatory and market considerations. Future directions point toward smart, personalized systems and AI-driven formulation strategies.