Background: Effective brain drug delivery remains a significant challenge due to the restrictive nature of the blood-brain barrier (BBB). This review article examines the mechanisms and recent advancements in brain drug delivery systems, addressing the challenges and factors influencing successful therapeutic interventions.

Objective: To provide a comprehensive overview of current technologies and strategies for enhancing drug delivery to the brain, with a focus on nasal-to-brain delivery systems.

Methods: We analyzed recent literature on various drug delivery systems, including nanoparticle-based formulations, liposomal technologies, and chemical permeation enhancers. We also evaluated the impact of factors such as drug properties, formulation characteristics, and physiological conditions on delivery efficacy.

Results: Advances in drug delivery systems have demonstrated significant progress in overcoming the BBB. Nanoparticle-based systems and liposomal formulations have shown enhanced permeability and targeted delivery capabilities. The nasal-to-brain route has emerged as a promising non-invasive strategy, utilizing the olfactory and trigeminal nerve pathways to facilitate direct access to the central nervous system. Formulations utilizing mucoadhesive polymers have improved drug solubility, stability, and residence time in the nasal cavity, leading to increased therapeutic effectiveness.

Conclusion: Understanding the mechanisms influencing brain drug delivery is crucial for developing effective treatments for neurological disorders. This review highlights the critical advancements in delivery systems, emphasizing the need for ongoing research to optimize strategies that enhance drug penetration across the BBB. Future studies should focus on refining these technologies to improve patient outcomes and address the growing burden of central nervous system diseases