Conjunctiva is a transparent film covering the whites of eyes and the inside of eyelids. When this film is inflamed, it is conjunctivitis. When the eyes are irritated by allergens, microorganisms and irritants in the environment, the blood vessels in this membrane will swell and make the eyes red. This disease is called allergic conjunctivitis. Allergic conjunctivitis is a disease caused by the excessive immune response of the immune system to allergens, and then spread to the conjunctiva.

Causes of allergic conjunctivitis

Allergic conjunctivitis is one of the most common diseases in ophthalmology outpatient department, including seasonal allergic conjunctivitis and perennial allergic conjunctivitis. Symptoms include itchy eyes, redness and swelling of eyelids and conjunctiva, burning sensation in eyes, foreign body sensation, increased watery secretion and photophobia.