The magnitudes of these reported incidences of allergic conjunctivitis and dry eye disease suggest that there could be significant comorbidity.5,6 The variable nature of dry eye pathophysiology has in large part prevented epidemiological studies on its coexistence in patients with allergic conjunctivitis. Dry eye and allergic conjunctivitis share signs and symptoms, complicating a differential diagnosis.5,6 Inflammation is a key feature in dry eye,7 and is known to be an important component of chronic ocular allergy.8–11 The tear film insufficiency and ocular surface inflammation present in dry eye disease might be expected to facilitate allergen entry and exacerbate allergic ocular signs and symptoms in a sensitized individual, but no studies have yet shown this association.