Intranasal drug delivery: an alternative for the administration of central acting drugs in horses: Administración intranasal de fármacos

The intranasal route is recognized as a very promising route for the systemic and cerebral administration of drugs in human medicine. It is a painless, noninvasive, economical, and practical administration route. Due to its characteristics, it is very useful for the application of drugs in noncooperative patients, as well as those with oral alterations or diarrhoea or, being a potential direct route to the central nervous system (CNS). However, its use in veterinary medicine is very rare, except for the administration of local treatments. Even though there are no complete and thorough studies on the anatomophysiological characteristics of the nasal cavity in the equine species, its large surface area and irrigation and consequent potential absorption area suggest a promising alternative for the systemic administration of drugs. In the present article, the characteristics of the nasal cavity of horses in relation to the various routes of systemic absorption and nose-brain passage of drugs are discussed, as well as the potential applications of this route of administration.