nanocapsules emulsion h nanoparticles t �� famotidine routes of administeration microparticles fig indomethacin concentrations attained in the aqueous humor following the topical application, in rabbits, of indomethacinloaded carriers and a control drug solution mean values � sd, n = , p famotidine routes of administeration compared with indocollyre p compared with colloidal suspensions reprinted from ref , with permission from pharmaceutical press immunosuppressive peptide cyclosporin a interestingly, following topical administration of pecl nanocapsules containing cyclosporin a, we observed metronidazole diareah corneal levels of the drug which were five times higher than those provided by an oily solution topical formulation of cyclosporin typically used these high levels were not, however, translated into high drug concentrations in the aqueous humor a result that was attributed famotidine routes of administeration to the important hydrophobicity of this peptide and its tendency to associate with lypophylic components famotidine routes of administeration therefore, at present, there is a proofofconcept of famotidine routes of administeration the efficacy of polyester nanocapsules for enhancing the concentration of topically applied drugs in the corneal epithelium whether this enhanced concentration may famotidine routes of administeration or may not lead to a favored accumulation famotidine routes of administeration of the drug in the inner eye famotidine routes of administeration is expected to be largely dependent on the physicochemical characteristics of the drug polysaccharidebased nanoparticles the polyester polymers described above are hydrophobic polymers famotidine routes of administeration that need to be biodegraded into hydrophilic oligomers in order to be eliminated from the body a very different class of polymers, famotidine routes of administeration which has only received attention in the last few years, is the one represented by the hydrophilic polysaccharides hyaluronic acid and chitosan are two types of polysaccharides which have opened famotidine routes of administeration new prospects in the ocular drug delivery area the choice of hyaluronic acid has been famotidine routes of administeration justified by its bioadhesive character, but also by its well known safety profile in fact, hyaluronic acid is already being used as a famotidine routes of administeration substitute for vitreous humor in intraocular surgery, since it constitutes a basic component of the famotidine routes of administeration vitreous body on the other hand, chitosan is a polycationic biopolymer which exhibits several favorable biological properties for ocular drug administration these properties include mucoadhesiveness biodegradability in the rich lysozyme containing mucus ie ocular mucosa, and also wound healing and antimicrobial activity despite the number of articles showing the efficacy of hyaluronic famotidine routes of administeration acid solutions for improving the retention of drugs applied topically onto the eye, the only particulate formulation that has been tested in vivo was composed of microparticles zm rather than nanoparticles these hyaluronate microparticles were shown to increase famotidine routes of administeration the residence time of the model drug methylprednisolone at the ocular surface of the rabbit famotidine routes of administeration eye taking into account the reported influence of the size on the interaction of particles with the ocular mucosa, we have recently designed famotidine routes of administeration nanoparticles consisting of hyaluronic acid and chitosan famotidine routes of administeration at present, we know that these nanoparticles are stable upon incubation in simulated lachrymal fluids famotidine routes of administeration and in vivo studies are in progress in order to evaluate their mechanism of interaction with the ocular mucosa chitosan has also received significant attention in the ophthalmic field one famotidine routes of administeration of the chitosanbased systems that has exhibited an interesting behavior following topical ocular administration, is famotidine routes of administeration the one consisting of chitosan nanoparticles these nanoparticles have been tested on the rabbit model for their ability to enhance the concentration of cyclosporin a at the level of the ocular mucosa as expected, the results showed that famotidine routes of administeration the chitosan nanoparticles were able to increase famotidine routes of administeration the concentrations of cyclosporin a in the external ocular tissues cornea and conjunctiva significantly for up to hr postinstillation fig despite this enhanced retention of the drug in the external tissues, the levels attained in the internal ocular famotidine routes of administeration structures ie aqueous humor, iris and ciliary body and in the blood were negligible consequently, these results suggested the utility of this new formulation for the treatment of surface eye diseases, ie dry eye or inflammatory diseases famotidine routes of administeration these high drug concentrations restricted to the periocular tissues were later explained by a high corneal and conjunctival surface retention of chitosan nanoparticles famotidine routes of administeration indeed, in a study consisting of evaluating the concentration of fluorescent chitosan, either in the famotidine routes of administeration form of nanoparticles or as a solution, in cornea and conjunctiva, we could conclude that the affinity of chitosan for the ocular surface is greater when it is in a particulate form this conclusion invites interesting prospects with regard to the potential of chitosan nanoparticles famotidine routes of administeration as drug carriers for topical ocular administration keeping this in mind, we tested the acute famotidine routes of administeration tolerance of chitosan nanoparticles following topical instillation famotidine routes of administeration to rabbits very recently the results gave evidence famotidine routes of administeration of an excellent tolerance, without any sign of irritation or damage of the ocular surface famotidine routes of administeration structures cya concentration in the cornea ng cyag cornea ?