Topic overview

Start with the big picture

This topic introduces formulation strategies for improving ocular and nasal drug delivery. For ocular products, it explains how tear turnover, the corneal barrier, and drainage limit bioavailability, then surveys approaches to extend precorneal residence or support targeted delivery. These include in-situ gels, mucoadhesive polymers, particulate carriers, and controlled-release implants, alongside key formulation considerations such as sterility, pH, isotonicity, and absorption-enhancing excipients. The nasal section covers systemic and nose-to-brain delivery, particle-size considerations, dosage forms, formulation specifications, and absorption enhancers. It also examines nasal barriers—including mucociliary clearance and enzymatic degradation—and how targeted carriers may use olfactory pathways for central nervous system delivery.