Red and itchy eyelids result from a variety of causes, the most common of which include allergies and infectious or inflammatory conditions of the eyelids such as blepharitis, chalazion and styes, as Healthgrades explains. Other common causes include lack of sleep, the common cold and conjunctivitis.
Eye allergies, also known as ocular allergies or allergic conjunctivitis, affect one in five Americans, according to WebMD. An eye allergy is an immune reaction that occurs when the eye of a sensitive person makes contact with an allergen such as pollen, dander or smoke, causing the body to release histamines, as explained by Healthline. The treatment of allergic conjunctivitis includes avoiding allergy triggers, sterile saline rinses and eye lubricants to help remove irritants, decongestant eye drops to curb eye redness, and taking oral antihistamines such as loratadine and cetirizine, according to WebMD.
Blepharitis, or irritation of the eyelids, is caused by bacterial or skin conditions such as dandruff of the scalp or acne rosacea. It is characterised by red, itchy eyelids and the crusting of the eyelids. Its treatment involves frequent scalp and face washing. Patients with blepharitis should also limit eye make up application and soak the eyelids with warm compresses, according to the American Optometric Association.