Penetration enhancers for the development of intranasal formulations for use in equines

Abstract

The aim of this review is to assess penetration enhancers, such as cyclodextrins, chitosan and their derivatives, surfactants, bileacids, their salts and derivatives, sodium taurodihidrydrofusidate, and phospholipids used in the development of intranasalformulations with a potential application in horses. In the last few years, the interest in the intranasal administration routein humans has grown because it is bloodless, noninvasive, and painless and represents a direct path toward the centralnervous system. However, in equine medicine, the use of this administration route is scarce. Since equines have a nasal cavitywith large surface area and blood irrigation, a high bioavailability of intranasal administered drugs is expected. Nowadays,the development of formulations for intranasal administration in equines is a challenge. The present review proposes theassessment of the characteristics and potential effects of the most important penetration enhancers in the development ofintranasal formulations for use in equines.