Menthol in Combination with Iontophoresis Promotes Natamycin Penetration through the Cornea: In Vitro and In Vivo Studies

We studied whether menthol can promote penetration of natamycin, a representative antifungal macrolide agent, through the cornea. Natamycin penetration was examined using an in vitro iontophoresis system that simulates clinical scenario; menthol (0.1-0.3%, w/v) was added to the donor reservoir of a standard Franz diffusion chambers. In vivo effects of menthol on natamycin penetration were examined in a set of bioassays using rabbits inoculated with Aspergillus fumigatus in the right eye. Potential irritation to the rabbit eye was examined using a standard test. Menthol significantly ( p