Abstract
The present study aimed to evaluate the potential usefulness of nasal route for brain delivery of poorly soluble drug, dexamethasone. Dexamethasone was solubilized using water-soluble cyclodextrin (W-CD), mono-maltosyl-β-cyclodextrin (GCD), and high concentration of dexamethasone (1.57%) was prepared. Nasal absorption study was conducted in rats using an improved in situ nasal deposit method. The serum dexamethasone concentration increased rapidly following nasal administration of GCD based formulation and the bioavailability of dexamethasone was equal to that of intravenous administration. In addition, brain edema caused by a cryogenic brain injury was more significantly improved by nasal administration of the dexamethasone-GCD formulation than by intravenous administration, suggesting that dexamethasone was delivered to the brain via nasal route. The nasal delivery of dexamethasone using a cyclodextrin inclusion formulation may have potential for an alternative therapeutic strategy for the brain edema therapy.
