The ear has multiple targets for allergic diseases (Table 9.1). The external ear may be afflicted with contact dermatitis to earrings or hearing aid molds, eczema, or sensitization to eardrops or fungus. The middle ear may be plagued with persistent effusion secondary to eustachian tube dysfunction or chronic inflammatory response to allergens. The inner ear may be troubled by Meniere’s disease and cochlear hydrops, both disorders with possible allergic bases.