Bioadhesive Buccal Delivery Systems

The buccal route offers a viable alternative to conventional drug delivery methods by enabling non-invasive administration, circumventing hepatic first-pass metabolism, and improving patient adherence. These benefits are attributed to the rich vascularisation, accessibility, and permeability of the buccal mucosa. This chapter presents an overview of the anatomical and physiological features of the oral cavity, with a focus on the buccal mucosa and the key factors influencing buccal drug absorption. Emphasis is placed on the critical role of bio-/mucoadhesive polymers in enhancing dosage form retention on the mucosal surface, thereby improving both local and systemic therapeutic outcomes. A wide range of mucoadhesive buccal delivery systems – including gels, tablets, films, and patches – are covered, exploring both conventional fabrication methods and advanced technologies such as 3D printing, electrospinning, and nanotechnology. The in vitro and in vivo performance of these drug delivery systems is highlighted, particularly their mucoadhesive, drug release, permeation, and pharmacokinetic properties. The chapter also explores the development of hybrid formulations, such as nanoparticle-embedded gels and patches, which integrate multiple delivery strategies. These advancements in formulation and fabrication technologies hold considerable promise for addressing the limitations of conventional buccal delivery systems and improving the efficacy and precision of drug delivery.