ABSTRACT
Advantages of stable nanoemulsions over coarse emulsions include the possibility to design versatile dosage forms due to their smaller droplet size and higher surface area without the inherent flocculation, coalescence and creaming that may be associated with macroemulsions. This chapter focuses on the potential therapeutic applications and formulation constituents of nanoemulsions for ocular and injectable administration. The cationic nanoemulsion achieved significantly higher drug levels than the anionic nanoemulsion and the commercial solution in the aqueous humor and the scleraretina. Different formulation approaches and nanoparticulate drug delivery systems including liposomes, nanoparticles, nanoemulsions and micellar solutions have been employed to solubilize and parenterally deliver poorly soluble drugs. Parenteral nanoemulsions, like all parenteral products, are required to meet pharmacopeial specifications. Preservatives like benzalkonium chloride and parabens may be included in ophthalmic emulsions to prevent microbial spoilage of multi-dose ophthalmic nanoemulsions. Particle size distribution is one of the most important characteristics of a nanoemulsion.
