Meet the Allergens

The allergic reaction is the eye’s inflammatory response to normally harmless environmental substances, the allergens.^3,18 Allergens are the substances that are capable of causing an allergic reaction.¹⁸ Many allergens such as dust or pollen are airborne particles.¹⁸

Allergens that cause most Ocular Allergies

Allergens belong to protein families. They are categorised as indoor, outdoor, plant/animal food, or injected allergens:¹⁹

• Indoor: dust mites, animals, cockroaches, moulds
• Outdoor: grass, tree and weed pollens, mould spores
• Plant/animal food: fruits, vegetables, nuts, milk, eggs, shellfish, fish
• Injected: insect venoms, some therapeutic proteins

Substances that come into contact with the skin are also causes of allergic reactions to the eyelids, identical to contact dermatitis.¹⁵ Eyelid allergies frequently cause rashes or swelling and inflammation of the skin around your eyes.¹⁴ Such allergens are preservatives, metals, nail polish and cosmetics and eye drops.¹⁴