What is the cause of eye irritation?

Eye astringency, often caused by dry eye, dry eye also known as keratoconjunctivitis sicca, refers to any reason caused by tear quality and quantity abnormalities or dynamic abnormalities caused by tear film stability decline, and accompanied by eye discomfort, resulting in ocular surface tissue lesions as a general term for a variety of diseases. Some patients also complicated with systemic immune diseases. The most common symptoms of dry eye were dry eye, fatigue and foreign body sensation. Other symptoms included burning sensation, eye swelling sensation, eye pain, photophobia, redness, etc. The signs included bulbar conjunctival vasodilation, bulbar conjunctiva tarnishing, thickening, edema, narrowing or interruption of tear river, sometimes yellowish sticky filiform secretion was seen in the lower fornix, and corneal epithelium in the palpebral fissure area fell off in different degrees.