Allergy occurs when a person develops hypersensitivity reactions to substances (allergens) in the environment that are harmless to most people [1]. Atopy is an exaggerated immunoglobulin (Ig) E-mediated immune response, which develops in persons with hereditary (genetic) tendency to develop allergic disease [1]. Some of the most common atopic conditions include atopic dermatitis (eczema), asthma and allergic rhinitis. Atopic conditions affect 28–32% of the population [2] with children and young adults being most commonly affected [3]. Allergic eye diseases include seasonal and perennial allergic conjunctivitis (AC), vernal keratoconjunctivitis (VKC), atopic keratoconjunctivitis (AKC), giant papillary conjunctivitis (GPC) and contact dermatoconjunctivitis [3]. VKC and AKC are similar yet distinct chronic allergic eye entities that can cause significant ocular surface complications and lead to vision loss due to corneal scarring [1, 2]. Type I and type IV (delayed, cell-mediated) hypersensitivity reactions play important pathophysiologic roles, with mast cell activation being implicated in both diseases [2, 4]; however, inflammatory cell-mediated immunopathologic changes with activation and migration of helper T cells likely drive the development of vision loss [2, 4]. Early diagnosis and appropriate treatment is essential to avoid sight-threatening complications, to reduce relapses and to enhance patient self-care [3].