A compound, process and method for increasing external auditory canal patency while simultaneously preventing the occurrence of otitis externa is disclosed wherein an aerosolized mixture of lipid crystals comprised of a mixture of one or more lipids surfactants and one or more spreading agents selected from the group consisting of sterols, lipids, fatty acids, cholesteryl esters, phospholipids, carbohydrates, nucleic acids and proteins, in powder form, and one or more fluorocarbon propellants is administered directly to the external auditory canal. Upon administration, the propellant(s) are evaporated from the mixture and the lipid crystals are deposited upon an air/liquid interface resident upon epithelial tissue lining the external auditory canal. Upon contact of said lipid crystals with the epithelial lining, an amorphous spread film is formed thereupon so as to form a barrier against exogenous water while simultaneously and substantially decreasing the surface tension of said lining so as to increase the patency thereof. In a second preferred embodiment, a therapeutically active agent effective in the treatment of otitis externa is added to the mixture of lipid crystals and upon administration of said aerosol mixture, the amorphous spread film formed thereby carries said therapeutically active agent throughout the epithelium of the outer ear canal so as to improve the patency thereof by both reducing surface tension of said epithelial lining and by efficiently treating the inflammatory process. In an alternate preferred embodiment, the afore-mentioned reduction of surface tension and delivery of therapeutically active agents is provided by a mixture of lipid crystals comprised of surfactant(s), therapeutically active agents and a propellant in which such other components are not soluble. In an alternate preferred embodiment, the afore-mentioned reduction of surface tension and delivery of therapeutically active agents is provided by a mixture of lipid crystals comprised of surfactant(s), therapeutically active agents and a propellant in which such other components are not soluble.