Fexofenadine·HC1 is non-sedating histamine HI receptor antagonist that can he used for the treatment of seasonal allergic rhinitis. The objective of this study was to investigate whether the carriers of defonnable liposomes can enhance the transepithelial permeability of ferofenadine·HCl across the in vitro ALl human nasal monolay et model. Characterization of this model was achieved by bioelectric measurements and morphological studies. The passage 2 and 3 of cell monolayers exhibited the TEER value of 28521482 ohm x cm: on 11 days of seeding and maintained high TEER value for 3 days. The defonnable liposome of fexofenadine.HC1 was prepared with phosphatidylcholine (PC) and cholic acid using extruder method. The mean particle size was about 200 mn and the maximum entrapment efficiency of 33.0% was obtained in the formulation of 1% PC and 100 μg/ml ferofenadine·HC1. The toxicity of the defonnable liposome to human nasal monolayers was evaluated by MTT assay and TEER value change. MTT assay showed that it has no toxic effect on the nasal epithelial cells in 2-hour incubation when the PC concentration was below 1%. However. defonnable liposome could not enhance the transepithelial permeability (Pap,) and cellular uptake of ferofenadine·HC1. In conclusion. the in vitro model could be used in nasal drug transport studies and evaluation of transepithelial permeability of formulations.